i

Publication Date: 11-01-11

1
Federal Highway Administration Accelerated Bridge Construction Manual 

2
Federal Highway Administration Accelerated Bridge Construction Manual 

Foreword

This manual has been developed for the purposes of enhancing the use of Prefabricated 

Bridge Elements and Systems (PBES) as part of accelerated construction projects. 

FHWA continues to focus on a need to create awareness, inform, educate, train, assist 

and entice State DOT’s and their staff in the use of rapid construction techniques. 

Users of this manual will be able to perform the following tasks:

• Understand the different types of ABC technologies that are in use today

• Understand the various types of prefabricated elements used in bridges

• Assess specific sites for the most appropriate ABC technology for the project

• Plan and implement an accelerated bridge construction program using PBES.

• Understand the construction aspects of PBES projects.

• Understand the long-term durability of bridges built with PBES

 

Byron Lord Myint Lwin

Program Coordinator, Team Leader Director

Highways for LIFE Program Office of Bridge Technology

Notice

This document is disseminated under the sponsorship of the U.S. Department of 

Transportation in the interest of information exchange. The U.S. Government assumes 

no liability for its content or use thereof. This report does not constitute a standard, 

specification, or regulation.

The U.S. Government does not endorse products or manufacturers. Trademarks or 

manufacturers’ names appear in this report only because they are considered essential 

to the objective of the document. 

3
 

 

 

 

 

 

 

 

 

 

Technical Report Documentation Page 

1. Report No. 

FHWA-HIF-12-013

2. Government Accession No. 3. Recipient’s Catalog No. 

4. Title and Subtitle 

Accelerated Bridge Construction - Experience in Design, Fabrication and 

Erection of Prefabricated Bridge Elements and Systems 

5. Report Date 

November 1, 2011 

6. Performing Organization Code 

7. Author(s) 

Michael P. Culmo, P.E. 

8. Performing Organization Report No. 

9. Performing Organization Name and Address 

CME Associates, Inc. 

333 East River Drive, Suite 400 

East Hartford, CT 06108 

Applied Research Associates, Inc. 

100 Trade Centre Drive, Suite 200 

Champaign, IL 61820 

10. Work Unit No. 

11. Contract or Grant No. 

DTFH61-06-D-00038/T-09002 

12. Sponsoring Agency Name and Address 

Office of Bridge Technology, HIBT-10 

Federal Highway Administration 

6300 Georgetown Pike 

McLean, VA 22101-2296 

13. Type of Report and Period Covered 

Final Document 

14. Sponsoring Agency Code 

15. Supplementary Notes 

FHWA's Contracting Officer's Technical Representatives were Byron Lord and Mary Huie. The Task Order Manager was 

Benjamin Beerman, P.E. The authors are thankful for the generous support help from various reviewers in completing this work. 

16. Abstract 

This document represents the “State of the Practice” with respect to all aspects of accelerated bridge construction (ABC). The 

intent of this manual is to fill in the gaps left by publication of the previous manuals. The manual covers ABC techniques, 

project planning and scoping, implementing ABC in a Transportation Agency, prefabricated elements, long-term performance of 

prefabricated elements, construction and design. The manual can be used by transportation agencies to establish a successful 

accelerated bridge construction program. 

17. Key Words 

Bridges, connections, details, elements, prefabricated, 

concrete, streel, timber, FRP, precast 

18. Distribution Statement 

No restrictions. This document is available to the public through 

the National Technical Information Service, Springfield, VA 

22161. 

19. Security Classif. (of this report) 

Unclassified 

20. Security Classif. (of this page) 

Unclassified 

21. No of 

Pages 

346 

22. Price

 Form DOT F 1700.7 (8-72) Reproduction of completed pages authorized 

Federal Highway Administration Accelerated Bridge Construction Manual 

4
Federal Highway Administration Accelerated Bridge Construction Manual 

SI* (MODERN METRIC) CONVERSION FACTORS

APPROXIMATE CONVERSIONS TO SI UNITS

SYMBOL WHEN YOU KNOW MULTIPLY BY TO FIND SYMBOL

LENGTH

in inches 25.4 millimeters mm

ft feet 0.305 meters m

yd yards 0.914 meters m

mi miles 1.61 kilometers km

AREA

in2 square inches 645.2 square millimeters mm2

ft2 square feet 0.093 square meters m2

yd2 square yard 0.836 square meters m2

ac acres 0.405 hectares ha

mi2 square miles 2.59 square kilometers km2

VOLUME

fl oz fluid ounces 29.57 milliliters mL

gal gallons 3.785 liters L

ft3 cubic feet 0.028 cubic meters m3

yd3 cubic yards 0.765 cubic meters m3

NOTE: volumes greater than 1000 L shall be shown in m3

MASS

oz ounces 28.35 grams g

lb pounds 0.454 kilograms kg

T short tons (2000 lb) 0.907 megagrams (or 

"metric ton")

Mg (or 

"t")

TEMPERATURE (exact degrees)

o

F Fahrenheit 5 (F-32)/9

or (F-32)/1.8

Celsius oC

ILLUMINATION

fc foot-candles 10.76 lux lx

fl foot-Lamberts 3.426 candela/m2 cd/m2

FORCE and PRESSURE or STRESS

lbf poundforce 4.45 newtons N

lbf/in2 poundforce per square 

inch

6.89 kilopascals kPa

5
Federal Highway Administration Accelerated Bridge Construction Manual 

SI* (MODERN METRIC) CONVERSION FACTORS

APPROXIMATE CONVERSIONS FROM SI UNITS

SYMBOL WHEN YOU KNOW MULTIPLY BY TO FIND SYMBOL

LENGTH

mm millimeters 0.039 inches in

m meters 3.28 feet ft

m meters 1.09 yards yd

km kilometers 0.621 miles mi

AREA

mm2 square millimeters 0.0016 square inches in2

m2 square meters 10.764 square feet ft2

m2 square meters 1.195 square yards yd2

ha hectares 2.47 acres ac

km2 square kilometers 0.386 square miles mi2

VOLUME

mL milliliters 0.034 fluid ounces fl oz

L liters 0.264 gallons gal

m3 cubic meters 35.314 cubic feet ft3

m3 cubic meters 1.307 cubic yards yd3

MASS

g grams 0.035 ounces oz

kg kilograms 2.202 pounds lb

Mg (or 

"t") 

megagrams (or "metric 

ton")

1.103 short tons (2000 

lb)

T

TEMPERATURE (exact degrees)

o

C Celsius 1.8C+32 Fahrenheit o

F

ILLUMINATION

lx lux 0.0929 foot-candles fc

cd/m2 candela/m2 0.2919 foot-Lamberts fl

FORCE and PRESSURE or STRESS

N newtons 0.225 poundforce lbf

kPa kilopascals 0.145 poundforce per 

square inch

lbf/in2

 

*SI is the symbol for the International System of Units. Appropriate rounding should be made to comply with Section 4 of 

ASTM E380.

(Revised March 2003)

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Federal Highway Administration Accelerated Bridge Construction Manual 

Table of Contents

Listing of Figures...........................................................................................................13

Listing of Tables ............................................................................................................18

Listing of Acronyms.......................................................................................................19

ABC Definitions.............................................................................................................22

Accelerated Bridge Construction (ABC)

Conventional Bridge Construction

Time Metrics for ABC

Onsite Construction Time 

Mobility Impact Time

Prefabricated Bridge Elements and Systems (PBES)

Elements

Deck Elements

Beam Elements

Pier Elements

Abutment and Wall Elements

Miscellaneous Elements

Systems

Superstructure Systems

Superstructure/Substructure Systems

Total Bridge Systems

Glossary of Terms.........................................................................................................38

Chapter 1 Introduction WHY ABC?.............................................................................52

1.1. Purpose and Use of this Manual ....................................................................55

1.1.1. Intended Users.......................................................................................55

1.1.1.1. Decision Makers.............................................................................55

1.1.1.2. Project Managers ...........................................................................56

1.1.1.3. Bridge Designers ............................................................................56

1.2. Why use Accelerated Bridge Construction? ...................................................57

1.2.1. Benefits of ABC projects using PBES.....................................................59

1.2.1.1. Reduced Road User Impacts..........................................................59

1.2.1.2. Improved Worker and Motorist Safety.............................................60

1.2.1.3. Expedited Project Planning Process...............................................61

1.2.1.4. Improved Quality ............................................................................62

1.2.1.5. Improved Constructability ...............................................................64

1.2.1.6. Reduced Cost to Society ................................................................64

1.2.2. Positive Public Perception of ABC..........................................................66

1.2.2.1. Public Response to ABC Projects...................................................66

Chapter 2 Accelerated Bridge Construction Technologies..........................................69

2.1. Foundation and Wall Elements ......................................................................70

2.1.1. Continuous Flight Auger Piles (CFA)......................................................70

2.1.2. Geosynthetic Reinforced Soil Integrated Bridge System (GRS/IBS).......71

2.1.3. Prefabricated Pier Cofferdams ...............................................................73

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Federal Highway Administration Accelerated Bridge Construction Manual 

2.2. Rapid Embankment Construction...................................................................73

2.2.1. Expanded Polystyrene (EPS) Geofoam .................................................73

2.2.2. Accelerated Embankment Preload Techniques......................................74

2.2.3. Column Supported Embankment Techniques ........................................74

2.3. Prefabricated Bridge Elements and Systems .................................................75

2.3.1. Prefabricated Elements..........................................................................75

2.3.2. Prefabricated Systems ...........................................................................80

2.4. Structural Placement Methods .......................................................................80

2.4.1. Self Propelled Modular Transporters (SPMTs).......................................80

2.4.2. Longitudinal Launching ..........................................................................84

2.4.3. Horizontal Skidding or Sliding................................................................. 85

2.4.4. Other Heavy Lifting Equipment and Methods .........................................88

2.4.5. Conventional Cranes..............................................................................94

2.5. Fast Track Contracting...................................................................................95

2.5.1. Accelerated Project Delivery ..................................................................96

2.5.1.1. Design-Build (DB)...........................................................................96

2.5.1.2. Construction Manager General Contractor (CMGC) ..................... 100

2.5.2. Contracting Provisions .........................................................................103

2.5.2.1. Best Value Selection ....................................................................103

2.5.2.2. A+B and A+B+C Bidding ..............................................................105

2.5.2.3. Continuity of the Construction Process.........................................106

2.5.2.4. Incentive/Disincentive (I/D) Clauses .............................................106

2.5.2.5. Warranties....................................................................................108

2.5.2.6. Lane Rental..................................................................................109

2.6. Applicability of ABC Technologies to Different Bridge Projects ....................109

2.6.1. Rehabilitation of Existing Bridges .........................................................110

2.6.1.1. Deck Replacement .......................................................................110

2.6.1.2. Superstructure Replacement ........................................................116

2.6.1.3. Substructure Replacement ...........................................................117

2.6.2. Replacement of Existing Bridges and New Bridges..............................118

2.6.2.1. Staging.........................................................................................118

2.6.2.2. Full Closure and New Construction ..............................................119

2.6.3. Effect of Structure Type on ABC Methods............................................119

2.6.3.1. Curved, Skewed and Flared Bridges ............................................119

Bridges with Transverse Floor Beams......................................................121

2.6.3.2. (trusses and widely spaced girder bridges)...................................121

2.6.3.3. Box Culverts.................................................................................122

Chapter 3 PBES for ABC – Planning and Scoping Projects........................................123

3.1. ABC Decision Making Process ....................................................................124

3.2. Decision Process for Selection of Appropriate ABC Methods.......................124

3.2.1. Defining the Problem............................................................................125

3.2.1.1. Site Constraints ............................................................................125

3.2.1.2. Staging Areas...............................................................................130

3.2.1.3. Traffic Management......................................................................131

3.2.1.4. Right of Way Issues......................................................................135

3.2.1.5. Utilities..........................................................................................135

3.2.1.6. Local Government Constraints .....................................................136

3.2.1.7. Structure Type Options................................................................. 136

3.2.2. Flowcharts for Determination of Appropriate ABC Methods..................139

3.2.2.1. Example Project ...........................................................................144

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Federal Highway Administration Accelerated Bridge Construction Manual 

3.2.3. Structure Type Selection Analysis Including Overall Project Costs.......150

3.2.3.1. Cost Evaluation ............................................................................150

3.2.4. Public Involvement...............................................................................158

Chapter 4 Implementing ABC in a Transportation Agency (A Case Study from the Utah 

DOT)160 .....................................................................................................................160

4.1. General Approach: No Magic Bullet .............................................................160

4.1.1. Strategic Layers of Implementation ......................................................162

4.1.2. Upper Management and Politics ..........................................................162

4.1.3. Mid-Level and Organization ................................................................. 162

4.1.4. Project Level ........................................................................................164

4.1.5. Identify ABC Champions at All Levels ..................................................165

4.2. Stakeholder Buy-in ......................................................................................165

4.3. Scanning Tours............................................................................................165

4.4. Demonstration Projects................................................................................166

4.5. The Role of Innovative Contracting..............................................................166

4.6. PBES Decision Making Framework .............................................................167

4.7. Establish a “Program of Projects”................................................................. 167

4.8. Develop Specifications, Standards, and Standard Details............................168

4.9. Communication............................................................................................168

4.10. Measure and Share Successes ...............................................................169

4.11. Conclusions .............................................................................................170

Chapter 5 Prefabricated Bridge Elements................................................................. 171

5.1. Materials ......................................................................................................171

5.1.1. Structural Steel ....................................................................................171

5.1.2. Concrete (Normal Weight and Lightweight)..........................................171

5.1.3. Timber..................................................................................................175

5.1.4. Aluminum.............................................................................................176

5.1.5. Fiber-Reinforced Polymer ....................................................................176

5.1.6. Grouts ..................................................................................................176

5.1.6.1. Grout Types..................................................................................177

5.1.7. Ultra High Performance Concrete ........................................................178

5.1.8. Corrosion Resistant Reinforcing Steel..................................................179

5.1.8.1. Stainless Steel..............................................................................179

5.1.8.2. Low-carbon, Chromium, Steel Bars ..............................................180

5.1.8.3. Coated and Galvanized Bars........................................................180

5.1.8.4. Fiber Reinforced Polymer (FRP) Bars ..........................................180

5.2. Superstructure Elements .............................................................................181

5.2.1. Beams and Girders ..............................................................................181

5.2.1.1. Steel.............................................................................................181

5.2.1.2. Precast/Prestressed Concrete......................................................181

5.2.2. Stay-in-place Deck Forming ................................................................. 182

5.2.2.1. Corrugated Steel ..........................................................................182

5.2.2.2. Partial-depth Precast Concrete Deck Panels................................182

5.2.3. Full-Depth Deck Panels........................................................................184

5.2.3.1. Precast/Prestressed Concrete......................................................184

5.2.3.2. Steel Grid .....................................................................................187

5.2.3.3. Fiber Reinforced Polymer.............................................................194

5.2.4. Modular Superstructure Systems .........................................................194

5.2.4.1. Modular Steel Systems................................................................. 195

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Federal Highway Administration Accelerated Bridge Construction Manual 

5.2.4.2. Modular Precast Concrete Superstructure Systems .....................199

5.2.4.3. Modular Timber Superstructure Elements and Systems ...............201

5.3. Substructure Elements.................................................................................203

5.3.1. Piers.....................................................................................................203

5.3.1.1. Open Frame Bents .......................................................................203

5.3.1.2. Wall Piers .....................................................................................206

5.3.1.3. Seismic Requirements..................................................................207

5.3.2. Abutments............................................................................................210

5.3.2.1. Cantilever.....................................................................................211

5.3.2.2. Spill-Through................................................................................212

5.3.2.3. Integral and Semi-Integral Abutments...........................................212

5.3.2.4. Geosynthetic Reinforced Soil Integrated Bridge System (GRS)....214

5.3.2.5. Seismic Requirements..................................................................215

5.3.3. Wing Walls and Retaining walls ...........................................................216

5.3.3.1. Precast Concrete Cantilever.........................................................216

5.3.3.2. Modular Precast ...........................................................................217

5.3.4. Modular Culvert/Arch Systems .............................................................219

5.3.4.1. Precast Arches and Three Sided Frames .....................................219

5.3.4.2. Steel Arches and Pipes ................................................................220

5.3.4.3. Box Culverts.................................................................................221

5.4. Foundations................................................................................................. 221

5.4.1. Common Deep Foundations ................................................................221

5.4.2. Foundation Challenges ........................................................................222

5.4.2.1. Earth Retention ............................................................................222

5.4.2.2. Deep Water..................................................................................223

5.4.3. Prefabricated Foundation Elements .....................................................223

5.4.3.1. Spread Footings ...........................................................................223

5.4.3.2. Pile Cap Footings .........................................................................224

5.4.3.3. Precast Pier Box Cofferdams .......................................................224

Chapter 6 Miscellaneous Bridge Elements ...............................................................228

6.1. Deck Overlays I Riding Surface Quality .......................................................228

6.2. Bridge Deck Expansion Joints .....................................................................229

6.3. Bridge Bearings ...........................................................................................229

6.4. Drainage Assemblies...................................................................................230

6.5. Barriers and Railings....................................................................................230

6.5.1. Crash Testing Requirements................................................................231

6.5.2. Concrete Barriers.................................................................................231

6.5.3. Metal Railings ......................................................................................232

6.5.4. Barriers on MSE and Modular Walls.....................................................232

6.6. Utilities.........................................................................................................233

Chapter 7 Construction.............................................................................................234

7.1. Shoring Systems and Temporary Works......................................................234

7.1.1. Shoring for Large-scale Bridge Moves .................................................234

7.1.2. Geotechnical Investigations ................................................................. 237

7.2. Acceleration of Submissions and Reviews...................................................238

7.2.1. Electronic Data Transfer.......................................................................238

7.2.1.1. Electronic Shop Drawing and Submittals......................................239

7.2.1.2. Digital Stamps and Signatures .....................................................239

7.2.2. “Intent to build” Drawings .....................................................................239

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Federal Highway Administration Accelerated Bridge Construction Manual 

7.3. Materials Testing on ABC Projects...............................................................240

7.3.1. Accelerated Testing Protocol................................................................240

7.3.2. Concrete Maturity Method ....................................................................240

7.3.3. Load Indicating Washers for Steel Structures.......................................241

7.4. Fabrication...................................................................................................241

7.4.1. Plant Certification.................................................................................241

7.4.2. Near-site Casting Certification..............................................................242

7.4.3. Tolerances ...........................................................................................242

7.4.3.1. Element Tolerances......................................................................242

7.4.3.2. Dimensional Growth .....................................................................243

7.4.3.3. Hardware Tolerances ...................................................................243

7.4.4. Lifting/Moving Elements .......................................................................244

7.4.5. Workmanship .......................................................................................245

7.5. Erection Issues ............................................................................................245

7.5.1. Responsibilities ....................................................................................245

7.5.1.1. Designer.......................................................................................245

7.5.1.2. Contractor ....................................................................................246

7.5.1.3. Fabricator.....................................................................................246

7.5.2. Large-scale Bridge Lifting.....................................................................246

7.5.3. The Effect of Tolerances and Adjustability............................................248

7.6. Field Inspection............................................................................................248

7.6.1. Accelerated Decision Making ...............................................................248

7.6.2. Staff Training........................................................................................250

7.7. Grout Placement and Curing........................................................................250

7.7.1. Small Void Grouting .............................................................................250

7.7.2. Grouting of Post-tensioning Ducts........................................................251

7.8. High Early Strength Concrete ......................................................................251

7.8.1. Mix Design Approach ...........................................................................253

7.8.2. Accelerated Curing...............................................................................255

Chapter 8 Long Term Performance of Prefabricated Elements................................. 257

8.1. Inspection Preservation, and Maintenance ..................................................257

8.2. Durability of Modular Systems .....................................................................258

8.2.1. Case Studies in Durability ....................................................................259

8.2.1.1. Joints in Substructure Elements ...................................................259

8.2.1.2. Joints in Precast Concrete Deck Panels.......................................260

8.2.1.3. Large-scale Bridge Moves............................................................261

Chapter 9 Design and Analysis ................................................................................265

9.1. LRFD Design ...............................................................................................265

9.1.1. Precast Substructure Elements............................................................265

9.1.2. Deck Panel Elements...........................................................................266

9.1.3. ABC Issues not Covered in the LRFD Bridge Design Specifications ....267

9.1.4. Design of Bridges with Large-scale Lifting Methods .............................268

9.2. LRFR Ratings ..............................................................................................270

9.3. Design and Analysis of Temporary Works ...................................................270

9.4. Evaluation of Existing Structures..................................................................270

References.................................................................................................................. 270

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Federal Highway Administration Accelerated Bridge Construction Manual 

Appendices .................................................................................................................275 

Appendix A: Design Examples.........................................................................275 

Appendix B: Standard and Proprietary Products..............................................289 

Appendix C: Sample Construction Specifications ............................................ 290

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Federal Highway Administration Accelerated Bridge Construction Manual 

Listing of Figures

Figure 

Number

Description Page

1.2-1 Cast-In-Place Concrete Bridge Construction Techniques 56 

1.2.1.4-1 Precast Deck Construction in 1990 63 

1.2.2.1-1 Sample Public Satisfaction Poll in Utah 67 

2-1 Accelerated Bridge Construction Technologies 68 

2.1.1-1 Continuous Flight Auger Pile Installation 69 

2.1.2-1 Typical Section of a GRS/IBS Bridge Abutment 71 

2.2.1-1 EPS Geofoam Embankment 73 

2.3.1-1 Prefabricated Cantilever Abutment 76 

2.3.1-2 Prefabricated Open Frame Pier Bent 76 

2.3.1-3 Modular Steel Superstructure Element Installation James 

River Bridge, Richmond, VA

77 

2.3.1-4 I-93 Superstructure Replacement Concept 78 

2.3.1-5 I-93 Superstructure Replacement Construction 78 

2.4.1-1 Sample Self Propelled Modular Transporter Configurations 80

2.4.1-2 SPMT Bridge Moves in Utah 81 

2.4.1-3 SPMT Bridge Move in Rhode Island 81 

2.4.2-1 Longitudinal Launching of a Utah Bridge 84 

2.4.3-1 Lateral Bridge Slide in Utah 85 

2.4.3-3 Lateral Bridge Slide in Oregon 86 

2.4.3-2 Lateral Bridge Slide of the Oakland Bay Bridge Approach 87 

2.4.4-1 Strand Jack Lifting of the Providence River Bridge 88 

2.4.4-2 Vertical Axis Pivot Technique 89 

2.4.4-3 Transverse Gantry Crane Installation Technique 90

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Federal Highway Administration Accelerated Bridge Construction Manual 

Figure 

Number

Description Page

2.4.4-4 Delivery of Modular Element using a Gantry Frame 90

2.4.4-5 Longitudinal Gantry Frame Installation Technique 92 

2.4.5-1 Precast Deck Panel Installation using Cranes 93 

2.4.5-2 Modular Element Installation using Cranes 94 

2.5.1.1-1 Sample Design-Build Process 98 

2.5.1.2-1 Sample CMGC Process 101 

2.6.1.1-1 Full Depth Precast Concrete Deck Panels 111 

2.6.1.1-2 Underside of Full Depth Precast Deck Panels

(after 19 years in service)

111 

2.6.1.1-3 Blind Pocket and Bar Slot Connection Details 113 

2.6.1.1-4 Precast Deck Panel Project in Texas

Based on NCHRP Report 584 Details

114 

2.6.1.2-1 Superstructure Installation Using SPMTs 115 

2.6.1.2-2 Completed Superstructure Replacement

Constructed with Prefabricated Elements

116 

3.2.1.2-2 Crane Access from Local Street 128 

3.2.1.3-1 SPMT Bridge Move over another Bridge 130

3.2.1.7-1 Construction of Drilled Shafts

(Prior to Removal of the Existing bridge)

137 

3.2.2-1 Decision Flowchart for Superstructure Construction over 

Roadway or Land

139 

3.2.2-2 Decision Flowchart for Superstructure Construction over 

Railroad or Transit

140

3.2.2-3 Decision Flowchart for Superstructure Construction over 

Water or Wetlands

141 

3.2.2-4 Decision Flowchart for Substructure Construction 142 

3.2.2.1-1 Existing Example Bridge Elevation 143 

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Federal Highway Administration Accelerated Bridge Construction Manual 

Figure 

Number

Description Page

3.2.2.1-2 ABC Flowchart for Example Bridge Superstructure 145 

3.2.2.1-3 ABC Flowchart for Example Bridge Substructure 146 

4.1-1 Sample ABC Implementation Flow Chart for a State Agency 160

5.1.2-1 Transparent View of a Cantilever Abutment Showing 

Corrugated Pipe Voids 

172 

5.1.2-2 Transparent View of an Integral Abutment Showing 

Corrugated Pipe Voids

173 

5.1.2-3 Sample Cast-in-place Closure Pour Detail 174 

5.1.7-1 Potential UHPC Connection for the NEXT Beam (Northeast 

Extreme Tee) 

178 

5.2.3.1-1 Precast Full Depth Deck Installation 185 

5.2.3.1-2 Precast Full Depth Deck Leveling System 185 

5.2.3.2-1 Exodermic Deck Details 188 

5.2.3.2-2 Exodermic Deck Installation 188 

5.2.3.2-3 Underside of the EffideckTM system 189 

5.2.3.3-1 Orthotropic Bridge Deck 190

5.2.3.3-2 Aluminum Deck Extrusion 191 

5.2.3.3-3 Trial Steel Sandwich Panel Bridge Deck 192 

5.2.4.1-1 Modular Steel Topped Multi-beam Units 195 

5.2.4.1-2 Folded Plate Modular Bridge Element 196 

5.2.4.1-3 Modular Orthotropic Deck Span 197 

5.2.4.1-4 Modular Orthotropic T-Beam Bridge Details 197 

5.2.4.2-1 Adjacent Deck Double Tee Beam Superstructure 198 

5.2.4.2-2 Adjacent Deck Bulb Tee Beam Superstructure 199 

5.2.4.3-1 Stress Laminated Timber Deck Span 201 

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Federal Highway Administration Accelerated Bridge Construction Manual 

Figure 

Number

Description Page

5.3.1.1-1 Precast Open Frame Pier Bent 203 

5.3.1.1-2 Precast Open Frame Pier Bent Sketch 204 

5.3.1.1-3 Precast Open Frame Pier Bent 204 

5.3.1.2-1 Precast Wall Pier 206 

5.3.1.3-1 Plastic Moment Connection Test, Cast-in-place Concrete 

Column-to-Cap

208 

5.3.1.3-2 Plastic Moment Connection Test, Precast Concrete Columnto-Cap208 

5.3.1.3-3 Grouted Post-tensioning Duct Connection 209 

5.3.2.1-1 Precast Concrete Cantilever Abutment 211 

5.3.2.3-1 Prefabricated Integral Abutment 212 

5.3.2.3-2 Semi-Integral Abutment 213 

5.3.2.4-1 GRS-IBS Bridge Example 214 

5.3.3.1-1 Precast Concrete Cantilever Wingwall 216 

5.3.3.2-1 Typical MSE Wall Details 217 

5.3.3.2-2 Modular Block Wall Example (T-WALL®) 218 

5.3.4.1-1 Con/Span® Bridge System 219 

5.4.3.2-1 Precast Pile Cap Footing 223 

5.4.3.3-1 Precast Concrete Pier Box Cofferdam 225 

5.4.3.3-2 Precast Concrete Pier Box Cofferdam Installation 226 

6.3-1 Adjustable Bearing Detail 229 

6.5-1 Precast Deck Panel with Integral Barriers 231 

7.1.1-1 Shipping Containers Used for Shoring 235 

7.1.1-2 Support Framing for SPMT Moves 236 

7.5.2-1 Strain Measurements During an SPMT Bridge Move 246 

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Federal Highway Administration Accelerated Bridge Construction Manual 

Figure 

Number

Description Page

7.8-1 Cracking in Closure Pour Concrete 252 

7.8.1-1 AASHTO Ring Test for Confined Concrete Shrinkage 254 

8.1-1 Recessed and Grouted Footing Joint 257 

8.2.1.1-1 Edison Bridge 259 

8.2.1.2-1 Connecticut Bridge 03200 260

8.2.1.2-2 Underside of Bridge 03200 after 19 Years in Service 260

8.2.1.3-1 Utah DOT I-80 Westbound Bridge Installation 261 

8.2.1.3-2 Typical Cracking on the I-80 Bridges 262 

8.2.1.3-3 Side-by-side Comparison 263 

A1.1-1 Typical Precast Concrete Deck Panel Installation 275 

A1.2-1 Precast Pier Supported on Piles 276 

A1.3-1 Precast Integral Abutment 278 

A1.3-2 Typical Section Through Abutment 279 

A1.4-1 Example Full Depth Precast Panel Lift 282 

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Federal Highway Administration Accelerated Bridge Construction Manual 

Listing of Tables

Table 

Number

Description Page

1 Deck Element Examples 29

2 Deck Beam Element Examples 31

3 Full Width Beam Element Examples 33

4 Pier Element Examples 34

5 Abutment and Wall Element Examples 35

6 System Examples 37

1-1 Planned SHRP2 Research Projects 53 

7.6.1-1 Construction Issue Resolution Ladder 248 

A1.5-1 Reference Documents that Include Design Information 287 

 

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Federal Highway Administration Accelerated Bridge Construction Manual 

Listing of Acronyms

The following is a listing of typical acronyms that may be found in this 

document.

Acronym Definition

ABC Accelerated Bridge Construction

ACCT Accelerated Construction Technology Transfer 

(FHWA Program)

ADT Average daily traffic

AMVA American Association of Motor Vehicle Administrators

AASHTO American Association of State Highway and 

Transportation

Officials

ACI American Concrete Institute

AISC American Institute of Steel Construction, Inc.

AISI American Iron and Steel Institute

AMTRAK National Railroad Passenger Corporation 

(Amtrak is not a governmental agency; it is a private 

company called the National Railroad Passenger 

Corporation)

ANSI American National Standards Institute

ASBI American Segmental Bridge Institute

ASCE American Society of Civil Engineers

ASTM American Society for Testing and Materials

BCA Benefit-Cost Analysis

C SHRP Canadian Strategic Highway Research Program

CD Compact Disc

CERF Civil Engineering Research Foundation

CFLHD Central Federal Lands Highway Division

CFR Code of Federal Regulations

CIP Cast-in-place

CRP Cooperative Research Program (TRB)

CSD Context sensitive design

DOT Department of Ttransportation

ECMT European Conference of Ministers of Transportation

EFLHD Eastern Federal Lands Highway Division

EIT Electronic information and technology

EPS Expanded Polystyrene

EU European Union

EUREKA European Research Coordination Agency

F SHRP Future Strategic Highway Research Program 

(now known as SHRP 2)

FAA Federal Aviation Administration

FAQs Frequently Asked Questions

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Federal Highway Administration Accelerated Bridge Construction Manual 

FHWA Federal Highway Administration

FRP Fiber-reinforced polymer

FY Fiscal year

GIF Graphic Interchange Format

GSA U.S. General Services Administration

GRS IBS Geosynthetic Reinforced Soil Integrated Bridge 

System

HBP Highway Bridge Program

HBRRP Highway Bridge Replacement and Rehabilitation 

Program

HITEC Highway Innovative Technology Evaluation Center

HRTS Office of Research and Technology Services

HSIP Highway Safety Improvement Program

HSS Hollow Structural Section

HTML HyperText Markup Language

IBRD Innovative Bridge Research and Deployment

IBTTA International Bridge, Tunnel and Turnpike Association 

ISTEA Intermodal Surface Transportation Efficiency Act of 

1991

ITE Institute of Transportation Engineers

JPEG Joint Photographic Experts Group

LCCA Life Cycle Cost Analysis

LRFD Load and resistance factor design

NAS National Academy of Sciences

NBI National Bridge Inventory 

NBIS National Bridge Inspection Standards

NCHRP National Cooperative Highway Research Program

NCSRO National Conference of State Railway Officials

NDE Nondestructive evaluation

NEXTEA National Economic Crossroads Transportation 

Efficiency 

Act of 1997

NHI National Highway Institute

NHS National Highway System

NHTSA National Highway Traffic Safety Administration

NIST National Institute of Standards and Technology

NRC National Research Council

NSF National Science Foundation

NTSB National Transportation Safety Board

OSHA Occupational Safety and Health Administration

PBES Prefabricated Bridge Elements and Systems

PCA Portland Cement Association

PCC Portland cement concrete

PCI Precast/Prestressed Concrete Institute

PDF Portable Document Format

PI Principal Investigator

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Federal Highway Administration Accelerated Bridge Construction Manual 

QC/QA Quality control/quality assurance 

R&D Research and development

ROI Return on Investment

SAFETEA Safe, Accountable, Flexible, and Efficient 

Transportation 

 Equity Act of 2003

SCOBS Subcommittee on Bridges and Structures (AASHTO)

SCOH Standing Committee on Highways (AASHTO)

SCOR Standing Committee on Research (AASHTO)

SHA State highway administration

SHRP Strategic Highway Research Program

TIFF Tagged Image File Format

TIG Technology Implementation Group

TRB Transportation Research Board

TRIS Transportation Research Information Services (TRB)

TRL Transportation Research Laboratory

USACE U.S. Army Corps of Engineers

USDOT U.S. Department of Transportation

WFLHD Western Federal Lands Highway Division

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Federal Highway Administration Accelerated Bridge Construction Manual 

Accelerated Bridge Construction (ABC)

DEFINITIONS

Accelerated Bridge Construction (ABC): 

ABC is bridge construction that uses innovative planning, design, materials, and 

construction methods in a safe and cost-effective manner to reduce the onsite 

construction time that occurs when building new bridges or replacing and 

rehabilitating existing bridges. 

ABC improves:

o Site Constructability

o Total project delivery time

o Material quality and product durability

o Work-zone safety for the traveling public and contractor personnel

ABC reduces:

o Traffic Impacts

o Onsite construction time

o Weather-related time delays

ABC can minimize:

o Environmental impacts

o Impacts to existing roadway alignment 

o Utility relocations and right-of-way take

A common reason to use ABC is to reduce traffic impacts because the safety of 

the traveling public and the flow of the transportation network are directly 

impacted by onsite construction related activities. However, other common and 

equally viable reasons to use ABC deal with site constructability issues. 

Oftentimes long detours, costly use of a temporary structures, remote site 

locations, and limited construction periods present opportunities where the use of 

ABC methods can provide more practical and economical solutions to those 

offered if conventional construction methods were used. 

Conventional Bridge Construction: 

Conventional bridge construction is bridge construction that does not significantly 

reduce the onsite construction time that is needed to build, replace, or 

rehabilitate a single, or group of bridge projects. Conventional construction 

methods involve onsite activities that are time consuming and weather 

dependent. 

22
Federal Highway Administration Accelerated Bridge Construction Manual 

An example of conventional construction includes onsite installation of 

substructure and superstructure forms, followed by reinforcing steel placement, 

concrete placement, and concrete curing, all typically occurring in a sequential 

manner. 

One of the reasons to minimize onsite construction activity is because the longterm presence of contractor related equipment, labor, and staging areas can 

present driver distractions and traffic disruptions that reduce the safety and 

mobility efficiencies of the transportation network. 

Time Metrics for ABC:

To gauge the effectiveness of ABC, two time metrics are used: 

Onsite construction time: 

The period of time from when a contractor alters the project site location until all 

construction-related activity is removed. This includes, but is not limited to, the 

removal of Maintenance of Traffic items, construction materials, equipment, and 

personnel. 

Mobility impact time: 

Any period of time the traffic flow of the transportation network is reduced due to 

onsite construction activities. 

Tier 1: Traffic Impacts within 1 to 24 hours

Tier 2: Traffic Impacts within 3 days

Tier 3: Traffic Impacts within 2 weeks

Tier 4: Traffic Impacts within 3 months

Tier 5: Overall project schedule is significantly reduced by months to 

years

Note: “Total project” time is the period of time from when project planning begins 

until the time that all bridge work is completed. Total project time adds a planning 

time component to the onsite construction time period. It is not a focused metric 

because planning time is needed regardless of whether a project is planned 

using ABC or conventional construction methods. Owners recognize that the use 

of ABC may require varying degrees of planning effort and resource allocations, 

but choose the ABC approach due to the site constraints, the many benefits of 

ABC, or a combination of the two. 

Prefabricated Bridge Elements and Systems (PBES):

Use of prefabricated bridge elements and systems (PBES) is one strategy that 

can meet the objectives of accelerated bridge construction. PBES are structural 

components of a bridge that are built offsite, or near-site of a bridge, and include 

features that reduce the onsite construction time and mobility impact time that 

occur from conventional construction methods. PBES includes innovations in 

design and high-performance materials and can be combined with the use of 

“Fast Track Contracting” methods. Because PBES are built off the critical path 

and under controlled environmental conditions, improvements in safety, quality, 

and long-term durability can be better achieved. 

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Federal Highway Administration Accelerated Bridge Construction Manual 

Regardless of the reason(s) to choose PBES, On-site construction time and 

Mobility impact time are typically reduced in some manner relative to 

conventional construction methods.

Elements: 

Prefabricated elements are a category of PBES which comprise a single 

structural component of a bridge. Under the context of ABC, 

prefabricated elements reduce or eliminate the onsite construction time 

that is needed to build a similar structural component using conventional 

construction methods. An element is typically built in a prefabricated and 

repeatable manner to offset costs. Because the elements are built under 

controlled environmental conditions, the influence of weather related 

impacts can be eliminated and improvements in product quality and longterm durability can be better achieved.

Deck Elements

Prefabricated deck elements eliminate activities that are 

associated with conventional deck construction, which typically 

includes onsite installation of deck forms, overhang bracket and 

formwork installation, reinforcing steel placement, paving 

equipment set up, concrete placement, and concrete curing, all 

typically occurring in a sequential manner. 

Examples of Deck Elements include:

o partial-depth precast deck panels 

o full-depth precast deck panels with and without 

longitudinal post-tensioning

o lightweight precast deck panels

o FRP deck panels

o steel grid (open or filled with concrete)

o orthotropic deck

o other prefabricated deck panels made with different 

materials or processes

Beam Elements

Prefabricated beam elements are composed of two types: “deck” 

beam elements” and “full-width” beam elements. 

Deck beam elements eliminate conventional onsite deck forming 

activities as noted above. To reduce onsite deck forming 

operations, deck beam elements are typically placed in an 

abutting manner. 

Examples of Deck Beam Elements include:

o adjacent deck bulb tee beams

o adjacent double tee beams

o adjacent inverted tee beams 

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Federal Highway Administration Accelerated Bridge Construction Manual 

o adjacent box beams

o modular beams with decks

o other prefabricated adjacent beam elements

Note: Although not preferred under the context of ABC, a separate 

construction phase (performed in an accelerated manner) may be 

required to finish the deck. A deck connection closure pour, 

overlay, or milling operation using innovative materials can be 

used to expedite the completion of the deck. In some situations, 

the placement of overlays can be accomplished during off-peak 

hours after the bridge is opened to traffic. 

Full-width beam elements eliminate conventional onsite beam 

placement activities. They are typically rolled, slid, or lifted into 

place to allow deck placement operations to begin immediately 

after placement. Given their size and weight, the entire deck is 

not included. 

Examples of Full-Width Beam Elements include:

o truss span without deck

o arch span without deck

o other prefabricated full-width beam element without 

deck

Pier Elements

Prefabricated pier elements eliminate activities that are associated 

with conventional pier construction, which typically includes onsite 

form installation, reinforcing steel placement, concrete placement, 

and concrete curing, all typically occurring in a sequential manner.

Examples of Pier Elements include: 

o prefabricated caps for caisson or pile foundations

o precast spread footings

o prefabricated columns

o prefabricated column caps

o prefabricated combined caps and columns

o other prefabricated pier elements

Abutment and Wall Elements

Prefabricated abutment and wall elements eliminate activities that 

are associated with conventional abutment and wall construction, 

which typically includes form installation, reinforcing steel 

placement, concrete placement, and concrete curing, all occurring 

in a sequential manner. 

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Federal Highway Administration Accelerated Bridge Construction Manual 

Prefabricated abutment and wall elements may be built in a 

phased manner using conventional construction methods, but 

under or near an existing bridge without disrupting traffic. 

Examples of Abutment and Wall Elements include:

o prefabricated caps for caisson or pile foundations

o precast footings, wing walls, or backwalls

o sheet piling (steel or precast concrete) 

o prefabricated full height wall panels used in front, 

behind, or around foundation elements 

o cast-in-place concrete abutments and walls used 

with or without precast elements if built in a manner 

that is accelerated, or has no impact to mobility

o MSE, modular block, or proprietary walls

o Geosynthetic Reinforced Soil (GRS) abutment

o Other prefabricated abutment or wall elements

Miscellaneous Elements

Prefabricated miscellaneous elements either eliminate various 

activities that are associated with conventional bridge construction 

or compliment the use of PBES. 

Examples of Miscellaneous Elements include:

o precast approach slabs

o prefabricated parapets

o deck closure joints

o overlays

Includes overlays that can be placed in an 

accelerated 

manner that complements or enhances the 

durability and rideability

of the prefabricated element

o other prefabricated miscellaneous elements

Note: Any cast-in-place concrete or overlay placement operation 

should be performed in a manner that reduces the impacts to 

mobility. This may require work that is performed under “Fast 

Track Contracting” methods with incentive/disincentive clauses, 

nighttime or off-peak hour timeframes, or work done entirely off 

line. Innovative materials may be needed to expedite placement 

times such as the use of rapid-set/early-strength-gain materials or 

ultra-high-performance concrete (UHPC) in closure pours. 

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Federal Highway Administration Accelerated Bridge Construction Manual 

Systems: 

Prefabricated Systems are a category of PBES that consists of an entire 

superstructure, an entire superstructure and substructure, or a total 

bridge that is procured in a modular manner such that traffic operations 

can be allowed to resume after placement. Prefabricated systems are 

rolled, launched, slid, lifted, or otherwise transported into place, having 

the deck and preferably the parapets in place such that no separate 

construction phase is required after placement. Due to the manner in 

which they are installed, prefabricated systems often require innovations 

in planning, engineering design, high-performance materials, and 

“Structural Placement Methods”. 

Benefits of using prefabricated systems include: 

o Minimal utility relocation and right-of-way take (if any at all)

o No- to- minimal traffic detouring over an extended period of time

o Preservation of existing roadway alignment

o No use of temporary alignments

o No temporary bridge structures

o No- to- minimal traffic phasing or staging

Superstructure Systems: 

Superstructure systems include both the deck and primary 

supporting members integrated in a modular manner such that 

mobility disruptions occur only as a result of the system being 

placed. These systems can be rolled, launched, slid, lifted, or 

transported in place, onto existing or new substructures 

(abutments and/or piers) that have been built in a manner that 

does not impact mobility. 

Examples of Superstructure Systems include:

o full-width beam span with deck

o through-girder span with deck

o truss span with deck

o arch span with deck

o other prefabricated superstructure systems

Superstructure/Substructure Systems:

Prefabricated superstructure/substructure systems include either 

the interior piers or abutments which are integrated in a modular 

manner with the superstructure as described above. 

Superstructure/substructure systems can be slid, lifted, or 

transported into place onto new or existing substructures that 

have been built in a manner that does not impact mobility.

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Federal Highway Administration Accelerated Bridge Construction Manual 

Examples of Superstructure/Substructure Systems include:

o rigid frames with decks and parapets

o other prefabricated superstructure/substructure

systems 

Total Bridge Systems: 

Total bridge systems include the entire superstructure and 

substructures (both abutments and piers) that are integral with the 

superstructure that are built off-line and installed in a manner to 

allow traffic operations to resume after placement. This excludes 

projects that are built off-line and, once complete, traffic is 

“shifted” to the new alignment. Total bridge systems typically 

require innovations in designs, high-performance materials, and 

“Structural Placement Methods” with or without the use of “Fast 

Track Contracting” methods. 

Examples of Total Bridge Systems include:

o total bridges of any kind rolled/launched/slid/lifted 

into place 

o rigid frames with decks, parapets and integrated 

substructures

o other prefabricated total bridge systems

The following pages contain examples of the most common prefabricated bridge 

elements and systems:

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Federal Highway Administration Accelerated Bridge Construction Manual 

Deck Elements Examples

Partial-depth precast deck 

panels 

Full-depth precast deck 

panels with and without 

longitudinal post-tensioning

Lightweight precast deck 

panels

Table 1 Deck Element Examples 

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Federal Highway Administration Accelerated Bridge Construction Manual 

Deck Elements Examples

FRP deck panels

Steel grid 

(open or filled with concrete)

Orthotropic deck

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Federal Highway Administration Accelerated Bridge Construction Manual 

Deck Beam Elements Examples

Adjacent deck bulb tee 

beams

Adjacent double tee beams

Adjacent inverted tee beams 

Table 2 Deck Beam Element Examples 

31
Federal Highway Administration Accelerated Bridge Construction Manual 

Deck Beam Elements Examples

Adjacent box beams

Modular beams with decks

32
Federal Highway Administration Accelerated Bridge Construction Manual 

Full Width Beam Elements Examples

Truss span without deck

Arch span without deck

Table 3 Full Width Beam Element Examples 

33
Federal Highway Administration Accelerated Bridge Construction Manual 

Pier Elements Examples

Prefabricated caps for 

caisson or pile foundations 

Precast spread footings

Prefabricated columns

Prefabricated column caps

Table 4 Pier Element Examples 

34
Federal Highway Administration Accelerated Bridge Construction Manual 

Abutment and Wall Elements Examples

Prefabricated caps for 

caisson or pile foundations

Precast footings, wing walls, 

or backwalls

Sheet Piling (Steel Or Precast 

Concrete)

Table 5 Abutment and Wall Element Examples 

35
Federal Highway Administration Accelerated Bridge Construction Manual 

Abutment and Wall Elements Examples

Prefabricated Full Height Wall 

Panels Used In Front, 

Behind, Or Around 

Foundation Elements

MSE, modular block, or 

proprietary walls

Geosynthetic Reinforced Soil 

(GRS) abutment

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Federal Highway Administration Accelerated Bridge Construction Manual 

System Examples

Superstructure Systems

Full-Width Beam Span With 

Deck

Total Bridge System

Total bridges of any kind 

rolled/launched/slid/lifted into 

place

Table 6 Prefabricated System Examples 

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Federal Highway Administration Accelerated Bridge Construction Manual 

Glossary of Terms

The following terms may be used in this document. The description of each 

term is written in the context of this document.

Term Description

accelerated bridge 

construction

Construction methods that result in an overall decrease in 

construction time when compared to the historic 

construction methods used to build bridges

additives Substances (typically chemical) that are added to a grout 

mixture to counteract the natural tendency of grouts to 

shrink. 

air release grouts A type of grout that does not rely on a chemical reaction to 

achieve expansion. The additive reacts with water to 

release air and cause expansion of the grout.

anchor rods Steel rods that are used to transfer loads from the 

superstructure to the substructure. Often referred to as 

“anchor bolts”, anchor rods differ in that they do not have a 

hexagonal head. Anchor rods are normally specified 

according to ASTM F1554.

approach slabs Structural slabs that span between the bridge abutments 

and the approach fill. They are used to span across the 

potential settlement of the approach roadway fills directly 

behind the abutments. 

backwall A structural wall element that retains the backfill soils 

directly behind the beam ends on a bridge abutment

barrier A structural wall element that is used to contain aberrant 

vehicles. They can be used on the bridge (parapet), or on 

the approach roadway.

batching The process of combining and mixing the materials to form 

concrete

bearing A structural element that connects the bridge 

superstructure to the substructure, while allowing for 

movements such as thermal expansion and contraction. 

benefit-cost analysis The comparison of benefits over time and of costs over 

time for proposed projects. BCA is a tool used to aid in 

public investment decision making by measuring the 

efficiency of spending from the viewpoint of net benefit to 

society.

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Federal Highway Administration Accelerated Bridge Construction Manual 

Term Description

bleed water (grout) Water that seeps out of the surface of a grout due to 

expansion of a grout in a confined or semi-confined area

blockouts Voids that are cast in prefabricated concrete elements that 

are used in connecting the elements in the field

bottom up estimating A process of construction estimating that breaks the 

individual tasks into discrete segments where the cost for 

time, equipment and materials can be determined for each 

segment. The total of all segments are then combined for 

the total construction estimate.

breastwall A wall that is typically non-structural that covers the beam 

ends at the corners of the bridge abutments. Sometimes 

referred to as “cheekwalls” by some states.

bridge deck A structural slab that spans between support elements 

(typically beams and girders) on a bridge. Bridge decks 

can be made of many materials, including reinforced 

concrete, steel, timber, fiber reinforced polymers, etc.

cable restrainers Structural elements that are used to restrain a bridge 

superstructure from excessive lateral movement during 

seismic events. The goal being to prevent the 

superstructure from falling off the substructure, which is a 

very common form of failure during seismic events.

camber A geometric adjustment of a bridge beam that is designed 

to compensate for the vertical deflection of the beam when 

subjected to dead loads. Camber is typically built into 

steel beams during fabrication. Camber is an inherent side 

effect of prestressed girder construction. 

carbon fiber A materials that is used in fiber reinforced polymer 

elements (FRP) to provide the structure performance. 

These fibers are oriented parallel to the direction of stress. 

cast-in-place concrete Concrete that is cast on site (as opposed to cast in a 

fabrication plant)

cheekwall A wall that is typically non-structural that covers the beam 

ends at the corners of the bridge abutments. Sometimes 

referred to as “breastwalls” by some states.

cofferdam An enclosure used to retain water and support excavation 

in order to create a dry work environment. Typically used 

for bridge substructure construction in rivers and along 

river banks.

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Federal Highway Administration Accelerated Bridge Construction Manual 

Term Description

composite beam action The process of connecting the bridge deck to the beams or 

girders to form a combined structural element.

composites The combining of multiple structural materials to form a 

structural element. 

compressive strength The value of uniaxial compressive stress reached when a

material fails.

concrete A construction material that consists of cement (commonly 

portland cement), coarse aggregates (such as gravel 

limestone or granite), fine aggregates (such as sand), and 

water. Often other materials are added to improve the 

structural properties such as chemical admixtures and 

other cementitious materials (such as fly ash and slag 

cement).

concrete/steel hybrid 

decks

A structural bridge deck system that combines structural 

steel elements with composite concrete to create a 

prefabricated deck system.

confinement steel Reinforcing steel used to contain the concrete core of a 

column when subjected to plastic deformations brought on 

by seismic loading.

consistency The state of a mixture of materials where the formulation is 

of uniform quality. 

constructability The extent to which a design of a structure provides for 

ease of construction yet meets the overall strength and 

quality requirements.

construction joints Joints in structures that are used to facilitate the 

construction of a portion of the structure. Construction 

joints typically have reinforcing steel passing from one side 

of the joint to the other providing continuity of the joined 

elements.

construction stages A process of building a bridge in segments in order to 

maintain traffic during construction.

continuity connection A connection used to connect two longitudinal bridge 

element (beams) to form a continuous bridge system. 

Typically these connections are only designed to resist live 

load.

continuous spans A structural system where the beams span across more 

than two supports without joints.

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Federal Highway Administration Accelerated Bridge Construction Manual 

Term Description

contraction joints Joints in structures that are used to allow the concrete 

elements to shrink without causing excessive cracking. 

Contraction joints typically do not have reinforcing steel 

passing from one side of the joint to the other.

controlled density fill See “flowable fill”.

conventional bridge 

construction

Construction methods that do not include prefabrication. 

Methods that employ non-adjacent butted girders that have 

cast-in-place (CIP) concrete deck and CIP concrete 

substructures.

cover concrete The specified minimum distance between the surface of 

the reinforcing bars, strands, posttensioning

ducts, anchorages, or other embedded items, and the 

surface of the concrete.

critical path The portion of the sequence of construction activities 

which represents the longest overall duration. This in turn 

determines the shortest time possible to complete a 

project.

cross frame A transverse structural element connecting adjacent 

longitudinal flexural element used to transfer and distribute 

vertical and lateral loads and to provide stability during 

construction. Sometimes synonymous with the term 

“diaphragm”.

crown The apex of the roadway cross slope.

curing compounds Chemical compounds that are used to prevent the rapid 

evaporation of water from concrete during curing.

curb A structural element that is constructed at the edge of the 

bridge deck that is used to contain rain water runoff. 

Curbs are often combined with structural railings to retain 

vehicles.

debonding The process of disconnecting prestressing strand from the 

surrounding concrete in a prestressed concrete element. 

This is done to control stresses in prestressed elements 

(typically at the ends of the element). 

deck The structural portion of a bridge that is directly beneath 

the wheels of passing vehicles.

dewatering The process of removing water from an excavation that is 

below the water table or surface of adjacent water.

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Federal Highway Administration Accelerated Bridge Construction Manual 

Term Description

diaphragm A transverse structural element connecting adjacent 

longitudinal flexural element used to transfer and distribute 

vertical and lateral loads and to provide stability during 

construction. Sometimes synonymous with the term “cross 

frame”.

differential camber A variation on the camber of two adjacent beams. See 

“camber”.

dimensional growth The phenomenon that results in the change in overall 

structure width or length when multiple elements are 

butted together. This is brought on by a build up of 

element side variations or tolerances that are a result of 

the fabrication process. 

distribution direction A direction that is normally parallel to the supporting 

members and is perpendicular to the direction of beam 

action in reinforced concrete slabs that are designed for 

one-way slab action. 

drilled shafts A deep foundation unit, wholly or partly embedded in the 

ground, constructed by placing fresh concrete in a drilled 

hole with or without steel reinforcement. Drilled shafts 

derive their capacity from the surrounding soil and/or from 

the soil or rock strata below its tip. Drilled shafts are also 

commonly referred to as caissons, drilled caissons, bored 

piles, or drilled piers.

dry pack grout A form of grout that has very stiff consistency that is placed 

by packing the material into voids by hand and hand tools.

effective prestress The stress or force remaining in the prestressing steel after 

all losses have occurred.

elastomeric bearing pads A type of structural bearing that is comprised of virgin 

neoprene or natural rubber. Sometimes combined with 

internal steel plates, fiberglass sheets, or cotton duck 

sheets.

emulation design A design method where a prefabricated connection is 

designed and detailed to act as (or emulate) a 

conventional concrete construction joint.

epoxy adhesive 

anchoring systems

A method of embedding reinforcing rods into hardened 

concrete to form a structural connection. The process 

involves a drilled hole and a chemical adhesive. Note: 

Epoxy adhesive anchoring systems should not be used in 

sustained tension applications.

42
Federal Highway Administration Accelerated Bridge Construction Manual 

Term Description

epoxy grouts Grout materials with chemical adhesives used in place of 

cementitious materials.

ettringite expansive grout Ettringite is crystal that forms as a result of the by product 

of reactive chemicals that can be interground into the 

cement in expansive grouts to produce non-shrink grout. 

exodermic bridge deck A bridge deck system that is composed of a steel grid deck 

combined with a top layer of concrete to form a composite 

system. This system differs from filled grid decks in that 

the concrete is placed above the top of the grid to 

maximize the composite action between the steel and the 

concrete.

expansion joints Joints in structures that are used to allow the concrete 

elements to expand and contract with temperature 

variation without causing excessive cracking. Expansion 

joints are similar to contraction joints except they are 

normally wider and often include a compressible material 

to allow for thermal expansion. They also do not have 

reinforcing steel passing from one side of the joint to the 

other.

fiber reinforced polymers 

(FRP)

A structural matrix of materials used to produce a 

structural element. FRP is commonly made reinforcing 

fibers that are combined with polyester, epoxy or nylon, 

which bind and protect the fibers from damage, and 

transfers the stresses between fibers. FRPs are typically 

organized in a laminate structure, such that each lamina 

(or flat layer) contains an arrangement of unidirectional 

fibers or woven fiber fabrics embedded within a thin layer 

of light polymer matrix material. The fibers, typically 

composed of carbon or glass, provide the strength and 

stiffness. 

filled steel grids A bridge deck system that is composed of a steel grid deck 

combined that is either fully or partially filled with concrete. 

flowable fill A material used to rapidly fill a void in embankment 

backfills or under structures without compaction. It 

normally has high flow characteristics. It is commonly 

made up of sand, water and a minor amount of cement. It 

is also referred to as “controlled density fill”.

flying wingwalls Walls used to retain embankment soils at the corners of 

abutments that are cantilevered from the end or rear of the 

abutment as opposed to being supported on a footing.

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Federal Highway Administration Accelerated Bridge Construction Manual 

Term Description

foam block fill A material made with expanded polystyrene (EPS) used to 

rapidly fill embankments where low unit weight materials 

are desired. This is often used over highly compressible 

soils such as clays. This material is also referred to as 

geofoam.

full-depth precast 

concrete deck slabs

A bridge deck system that is composed of reinforced 

concrete elements that when placed, make up the full 

structural deck system. 

gantry crane A crane type that is characterized by two or more legs 

supporting an overhead beam with a traveling trolley hoist.

gas generating grout A type of non-shrink grout that expands due to the 

production of gas during the curing process. The gas is 

generated by adding reactive materials to the mix (often 

aluminum) to produce the gas. 

geosynthetic reinforced 

soil integrated bridge 

system 

Geosynthetic Reinforced Soil (GRS) technology consists of 

closely spaced layers of geosynthetic reinforcement and 

compacted granular fill material. GRS–IBS includes a 

reinforced soil foundation, a GRS abutment, and a GRS

integrated approach. When integrated with a bridge 

superstructure, the system blends the embankment with 

the superstructure to act as a single unit with respect to 

settlement.

girder-floorbeam bridges A bridge framing system that is composed of main girders 

that run parallel to the centerline of the roadway combined 

with transverse floorbeams that support the deck. Often 

the system includes stringer beams that run between 

floorbeams (parallel to the roadway).

glue laminated wood A structural framing material that consists of multiple layers 

of dimensional lumber glued together to form a large 

timber element.

greenfield A construction area where a bridge or highway is being 

built on land that previously did not support a roadway or 

bridge.

grout A material (often cementitious or epoxy) that is used to fill 

voids between elements.

grouted reinforcing splice 

couplers

A proprietary product used to join precast concrete 

elements by connecting reinforcing steel bars at the ends 

of the elements. They consist of a steel casting sleeve 

that is filled with grout. The reinforcing bars are inserted 

44
Federal Highway Administration Accelerated Bridge Construction Manual 

Term Description

into the ends of the casting and developed by the 

interaction of the grout with the sleeve.

haunch The material between the top of a beam element and the 

bottom of the bridge deck that gaps the space between the 

two elements (also referred to as the “web gap” in some 

states). 

high early strength 

concrete

A concrete mixture that gains strength rapidly in order to 

accelerate construction. 

integral abutment A bridge abutment type that is made integral with the 

bridge superstructure through a combined shear and 

moment connection. They are often constructed with a 

single row of piles that allow for thermal movement and 

girder rotation. Soil forces behind the abutments are 

resisted through the strut action of the superstructure.

integral abutment 

connection

The connection between the superstructure and the 

integral abutment substructure that can resist both shear 

and moment.

integral pier connection The connection between the superstructure and the pier 

substructure elements that can resist both shear and 

moment.

keeper assemblies Devices that are placed on top of substructures to prevent 

lateral movement of the bridge superstructure. They are 

often used to resist lateral seismic forces. They can be 

constructed with structural steel or reinforced concrete.

leveling bolts Bolt assemblies embedded in various prefabricated 

elements that are used to make grade adjustments in the 

field during construction.

life-cycle cost analysis A process for evaluating the total economic worth of a 

usable project segment by analyzing initial costs and 

discounted future costs, such as maintenance, user costs, 

reconstruction, rehabilitation, restoring, and resurfacing 

costs, over the life of the project segment.

match casting A process of joining two precast concrete elements with 

high precision. This is done by casting one element 

against the adjoining element in the fabrication yard, 

separating them, and then re-joining them in the field. The 

field connection is normally made with thin epoxy 

adhesives combined with post-tensioning.

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Federal Highway Administration Accelerated Bridge Construction Manual 

Term Description

mechanical splices Devices used to connect reinforcing through mechanical 

means. Examples of these systems include grouted 

sleeves, wedge assemblies, and threaded bar ends. 

mechanically stabilized 

earth (MSE) retaining 

walls

A soil-retaining system, employing either strip or grid-type, 

metallic, or polymeric tensile reinforcements in the soil 

mass, and a facing element that is either vertical or nearly 

vertical. In this system, the soil mass is engaged by the 

strips to become a gravity type retaining wall.

mild reinforcement Steel bars or grids within concrete elements that are used 

to resist tension stresses. Mild reinforcement normally 

consists of deformed steel bars or welded wire fabric.

modular block retaining 

walls

A soil-retaining system employing interlocking soil-filled 

timber, reinforced concrete, or steel modules or bins to 

resist earth pressures by acting as gravity retaining walls.

near site fabrication A process of constructing prefabricated elements near the 

bridge construction site in order to minimize problems with 

shipping of large elements.

network arch bridge A type of tied arch that includes suspender cables that are 

run diagonally forming a crisscrossing pattern

non-shrink cementitious 

grout

A structural grout used for filling voids between elements 

that is formulated with cement, fine aggregates and 

admixtures. The admixtures are used to provide 

expansive properties of the material during curing. This 

expansion counteracts the natural tendency of cement 

grouts to shrink during curing.

one-way slab A reinforced concrete slab system that primarily spans 

between two parallel support members. In this system, the 

majority of the reinforcing runs perpendicular to the 

support members.

open grid decks A bridge deck system that is composed of an open steel 

grid spanning between supporting members. 

orthotropic bridge deck A steel bridge deck system comprised of a top deck plate 

supported by open or closed ribs that are welded to the top 

plate.

parapet A structural element that is constructed at the edge of 

bridge deck that is used to contain aberrant vehicles.

partial-depth precast A bridge deck system that consists of relatively thin 

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Federal Highway Administration Accelerated Bridge Construction Manual 

Term Description

concrete deck panels precast concrete panels that span between supporting 

members that are made composite with a thin layer of sitecast reinforced concrete. The precast panel makes up the 

bottom portion of the structural slab. The site cast 

concrete makes up the remainder of the structural slab.

pier box A prefabricated system that includes a precast concrete 

box that is placed over driven piles or drilled shafts. The 

box becomes the form to contain site cast reinforced 

concrete. Often pier boxes are used in water applications 

to form a cofferdam for the footing concrete.

pier cap A structural beam spanning between pier columns.

pier column The vertical structural element in a bridge pier

pile bent pier A bridge pier without a footing that is comprised of driven 

piles or drilled shafts supporting a pier cap.

pile cap footing A footing that is supported by driven piles or drilled shafts.

plastic hinge A method of dissipating lateral seismic forces by allowing 

portions of reinforced concrete pier columns to bend 

beyond the yield point. Stability of the structure is 

maintained by providing adequate confinement 

reinforcement.

post-tensioning ducts A form device used to provide a path for post-tensioning 

tendons or bars in hardened concrete

post-tensioning (PT) A method of prestressing in which the strands or bars are 

tensioned after the concrete has reached a specified 

strength.

precast concrete Concrete elements that are cast in a location other than 

their final position on the bridge.

prefabrication The process of building bridge elements prior to on-site 

construction in order to accelerate the construction of the 

bridge.

prefabricated bridge 

elements

Portions of a bridge structure that are constructed away 

from the final bridge site (see Definitions on page I-9)

prefabricated bridge 

systems 

Portions of a bridge structure that are made up of several 

elements that are combined to form a larger portion of the 

bridge suchs as the superstructure, substructure or the 

47
Federal Highway Administration Accelerated Bridge Construction Manual 

Term Description

entire bridge (see Definitions on page I-9)

prestressed concrete Concrete elements in which force is introduced into the 

element during fabrication to produce internal stresses that 

are normally opposite of the anticipated stresses in the 

completed structure. Prestressing can be accomplished 

with pretensioning or post-tensioning.

pretensioning A method of prestressing in which strands are tensioned 

before the concrete is placed, and released after the 

concrete has hardened to a specified strength.

quality assurance and 

quality control (QA/QC)

The process of inspection and control during fabrication to 

ensure that the specified quality is achieved.

reflective cracking A crack that can form in site cast concrete that is placed 

over a joint between two elements below the pour.

reinforced closure pours A method of connecting two prefabricated elements by 

casting a segment of reinforced concrete between two 

elements. The connection is often made using lap splices 

or mechanical reinforcing connectors.

reinforced concrete Concrete elements with reinforcing steel cast into the 

concrete to form a structural element. The steel is 

normally used to resist tension stresses in the element.

reinforcing steel Steel placed in concrete elements (either be mild 

reinforcement or prestressing steel).

return on investment Measurement of the efficiency of spending from the 

viewpoint of net benefit to society. ROI analysis is 

essentially identical to benefit/cost analysis, incorporating 

benefit concepts that do not directly result in a revenue 

stream. 

right of way The land used for the route of a railroad or public road

road user costs Costs that incurred by users of a highway network when 

they are delayed due to construction activities.

saturated surface dry 

(SSD) condition

A condition that is normally specified for concrete surfaces 

that are to be grouted. Saturated Surface Dry describes 

the condition of the concrete surface in which the pores 

are filled with water; however no excess water is on the 

surface. This condition minimizes the absorption of water 

from the grout into the surrounding concrete.

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Federal Highway Administration Accelerated Bridge Construction Manual 

Term Description

segregation A condition where the distribution of course or fine 

aggregates in the concrete or grout mix become nonuniform.

self-propelled modular 

transporter (SPMT)

A high capacity transport trailer that can lift and move 

prefabricated elements with a high degree of precision and 

maneuverability.

shear key A shaped joint between two prefabricated elements that 

can resist shear through the geometric configuration of the 

joint.

shear studs Headed steel rods that are welded to elements to provide 

composite action between two bridge elements. Typically 

used between beams and the deck slab.

sheeting A structural system used to retain earth and water and 

allow for excavation during the construction of a bridge 

substructure.

shims pack Flat plates placed between two prefabricated elements 

used to provide a specified separation. Shims are also 

used to make vertical grade adjustments. Shims are 

typically made of steel or polymer sheets.

shrinkage (grout) A property of cementitious concretes and grouts that 

occurs during curing where the material reduces in size. 

skew angle In most state agencies, this is defined as the angle 

measured between the centerline of the bridge elements 

(abutments, piers, joints, etc.) and a line perpendicular to 

the roadway alignment. (i.e. a bridge with zero skew is 

square bridge). This definition is used in this manual. 

Several states define the skew angle as the complimentary 

angle (i.e. a bridge with 90 degree skew is square).

spandrel wall A wall that is constructed on the sides of earth filled arch 

structures that are used to retain the fill soils.

spiral reinforcement Transverse reinforcement used in reinforced concrete 

columns to resist shear. Spirals are also used for 

confinement of the concrete core as a plastic hinge forms.

steel stay-in-place forms Corrugated steel sheeting that is used to support the wet 

concrete in a bridge deck during construction, and left in 

place in the permanent structure.

strength direction A direction that is normally perpendicular to the supporting 

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Federal Highway Administration Accelerated Bridge Construction Manual 

Term Description

members and is parallel to the direction of beam action in 

reinforced concrete slabs that are designed for one-way 

slab action.

stress laminated timber 

deck bridges

A timber bridge deck that is comprised of multiple layers of 

dimension lumber placed on edge and connected with 

transverse prestressing. Shear transfer between the 

laminations is accomplished through friction.

stringers There are two common uses for this term.

1. Longitudinal steel beams on short span multi-beam 

bridges.

2. Secondary framing members on floor beam type 

bridges that span from floor beam to floor beam. 

stub abutments A short cantilever type abutment that is constructed near 

the top of the approach embankment.

substructure The portion of the bridge that is below the beam and/or 

deck elements. It typically includes piers, abutments, and 

walls.

superstructure The portion of the bridge that is above substructure. It 

typically includes bearings, beams, girders, trusses, and 

the bridge deck.

surface preparation 

(grout)

The process of preparing a concrete surface for grouting 

by cleaning or intentionally roughening the surface. This is 

done to improve the adhesion of the grout to the concrete. 

It typically includes sand blasting, water blasting, or hand 

tool cleaning.

sweep The lateral curvature of a prefabricated element caused by 

fabrication form irregularities and/or internal stresses.

test pours and test mockupsA method of quality control whereas a contractor will build 

a model of a portion of the bridge structure that includes a 

void that requires grout placement. These are used to 

demonstrate proper grout placement in complex voids.

tied arch An arch structure where the thrust forces at the supports 

are resisted by a continuous bottom chord that runs from 

end to end.

timber deck panels Prefabricated timber panels that are made with glue 

laminated lumber.

tolerance Specified allowable dimensional variations in prefabricated 

50
Federal Highway Administration Accelerated Bridge Construction Manual 

Term Description

elements. The variations are a result of irregularities in 

formwork and minor deviations in measurements during 

fabrication.

transverse ties Reinforcement used in reinforced concrete columns to 

resist shear. Ties, if properly detailed, can also used for 

confinement of the concrete core as a plastic hinge forms.

tremie concrete pour Concrete that is placed underwater and within a cofferdam 

to resist the vertical pore pressure of the water below a 

footing during construction.

variable web gap See “Haunch”

water content The specified amount of water in a concrete or grout mix.

wearing surface The top portion of the bridge deck that is directly below the 

vehicle tires. Often wearing surfaces are designed to be 

sacrificial and replaceable.

wet curing Curing is the process of retaining sufficient moisture 

(water) in freshly placed grout/concrete to complete the 

hydration reaction which occurs when water is introduced 

to Portland cement. Wet curing leaves the freshly placed 

grout/concrete in an environment of 100 percent humidity

working time The amount of time that a concrete or grout mix remains in 

a liquid or plastic state so it can be placed and 

consolidated.

yield strength The stress at which an elastic material begins to deform in 

a plastic manner. Prior to yield, the material will deform 

elastically and will return to its original shape when the 

applied stress is removed. If loaded beyond yield and then 

unloaded, the material will not return to its original shape.

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Federal Highway Administration Accelerated Bridge Construction Manual 

Chapter 1 Introducti

on WHY ABC?

The use of Accelerated Bridge Construction (ABC) using Prefabricated 

Bridge Elements and Systems (PBES) has become more commonplace over 

the last 20 years in the United States. The use of ABC for the most part has 

been driven by acute traffic control issues at specific sites. Many of these 

projects simply had to be built with ABC. In recent years, more states are 

considering ABC on more typical projects. The desire to reduce impacts to 

the traveling public is driving this effort. 

During the last 20 years, there have been incremental advancements in the 

use of ABC. Early projects focused on specific prefabricated elements such 

as bridge decks or pier caps. For instance, bridge deck construction using 

full depth precast concrete deck panels have been in use for over 20 years. 

More recently, ABC projects that use Prefabricated Bridge Elements and 

Systems (PBES) have spread to all bridge elements including substructures 

and foundations. Some states have made or are moving toward making the 

use of ABC and PBES standard practice.

Several FHWA documents on the subject of PBES have been written 

and published including:

• Decision-Making Framework for Prefabricated Bridge Elements 

and Systems (PBES), Publication Number FHWA-HIF-06-030, 

May 2006 [1]

• Manual on the Use of Self-Propelled Modular Transporters to 

Remove and Replace Bridges, Publication Number FHWA-HIF07-022, June 2007 [2]

• Connection Details for Prefabricated Bridge Elements and 

Systems, Publication Number FHWA-IF-09-010, March 2009 [3]

All of these documents offer important information for the use of ABC 

with PBES; however none of these documents cover all the major 

aspects of an accelerated bridge construction project. Several sections 

in this manual cover some of the same information that is included in 

these other documents; therefore the subjects will be covered in less 

detail in this manual. This manual should be considered an overview 

manual on the subject of ABC with PBES. 

The Transportation Research Board is in the process of a significant 

research effort entitled the Strategic Highway Research Program 

(SHRP2). This wide ranging program focuses on the idea of rapid 

renewal for highway infrastructure. Three objectives have been 

identified to achieve renewal:

1. Perform construction rapidly

2. Cause minimal disruption

3. Produce Long-Lived facilities

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Federal Highway Administration Accelerated Bridge Construction Manual 

Most of the SHRP2 research efforts are directly applicable to ABC and 

this manual. The SHRP2 work is more specific and in more detail than 

the information included in this manual. Users of this manual should 

reference the SHRP2 work as they explore deeper into the field of ABC. 

Figure 1-1 is a table that outlines the SHRP2 planned research topics.

SHRP2 Rapid Renewal Research Activities

Project 

Number

Description

R01 Encouraging Innovation in Locating and Characterizing Underground Utilities

R02 Geotechnical Solutions for Soil Improvement, Rapid Embankment Construction, 

and Stabilization of the Pavement Working Platform

R03 Identifying and Reducing Worker, Inspector, and Manager Fatigue in Rapid 

Renewal Environments

R04 Innovative Bridge Designs for Rapid Renewal

R05 Modular Pavement Technology

R06 A Plan for Developing High-Speed, Nondestructive Testing Procedures for Both 

Design Evaluation and Construction Inspection

R07 Performance Specifications for Rapid Highway Renewal

R09 Risk Manual for Rapid Renewal Contracts

R10 Innovative Project Management Strategies for Large, Complex Projects

R11 Strategic Approaches at the Corridor and Network Level to Minimize Disruption 

from the Renewal Process

R15 Strategies for Integrating Utility and Transportation Agency Priorities in Highway 

Renewal Projects

R16 Railroad-DOT Institutional Mitigation Strategies

R19-A Bridges for Service Life beyond 100 Years: Innovative Systems, Subsystems, and 

Components

R19-B Bridges for Service Life beyond 100 Years: Service Limit State Design

R21 Composite Pavement Systems

R23 Using Existing Pavement in Place and Achieving Long Life

R26 Preservation Approaches for High Traffic Volume Roadways

The majority of the SHRP2 research will be completed in the near future, 

which will be followed by an implementation program. Bridge designers 

are encouraged to use this manual as a primer on ABC and then use the 

Figure 1-1 Planned SHRP2 Research Projects

53
Federal Highway Administration Accelerated Bridge Construction Manual 

SHRP2 work as a technical resource on specific issues regarding ABC 

and rapid renewal.

54
Federal Highway Administration Accelerated Bridge Construction Manual 

1.1. Purpose and Use of this Manual

This document represents the “State of the Practice” at this time with 

respect to most aspects of accelerated bridge construction. The 

intent of this manual is to fill in the gaps left following the publication 

of the previous manuals by presenting an overview of all aspects of 

the field of accelerated bridge construction, from project planning 

through detailing, to project delivery.

The FHWA has focused on 5 components of Accelerated Bridge 

Construction. They include:

• Foundation and Wall Elements

• Rapid Embankment Construction

• Prefabricated Bridge Elements and Systems

• Structural Placement Methods

• Fast Tracked Contracting

This manual will cover all of these topics in some detail. The subject 

of ABC is in a constant state of change. In the future, other new 

technologies may emerge that will be included in field Accelerated 

Bridge Construction. The FHWA will maintain a website for ABC that 

will be kept current with the latest ABC technologies.

1.1.1. Intended Users

1.1.1.1. Decision Makers

Project decision makers can range from agency 

management to project planners. The benefits of ABC go 

far beyond the actual construction; therefore agency 

managers need to be aware of the short-term and longterm benefits of this method of construction. 

This manual covers many aspects of the decision making 

process. Chapter 4 explores the ways to implement ABC 

technologies in a transportation agency. This covers the 

strategies for implementation at all levels of the agency. 

Success cannot be attributed to a single individual or unit 

within the DOT. It needs to be an organized approach that 

involved all members of the department, contractors, 

fabricators, and the consulting engineering community.

Before any project can get off the ground, a project 

normally goes through a planning process. Many agencies 

have teams devoted to project planning and preliminary 

design development. These teams do not normally get 

involved with the minutia of bridge analysis and design, but 

instead focus on the general approach to the project.

Chapter 3 explores the ABC decision processes that can 

be used during project planning and scoping to ensure that 

55
Federal Highway Administration Accelerated Bridge Construction Manual 

ABC is used where it is appropriate and can have a 

beneficial effect on the project. 

The previously published FHWA Manual entitled DecisionMaking Framework for Prefabricated Bridge Elements and 

Systems (PBES), Publication Number FHWA-HIF-06-030, 

May 2006 [1] is an excellent source of information on the 

process of planning a successful ABC project. Decision 

makers can use the decision making framework document 

combined with the information in this manual to make 

informed decisions regarding the most appropriate uses of 

the ABC. Several agencies have used the FHWA manual as 

a basis for development of decision making processes that 

are specific to their agencies. The Utah DOT has developed 

a process with weighted factors in lieu of the yes/no 

decisions in the FHWA manual. The Oregon DOT is 

working with several other states on a more elaborate 

project decision process that looks at many more factors and 

compares different construction approaches. This study will 

be completed in the next year and made available to all 

transportation agencies.

1.1.1.2. Project Managers

Once a decision has been made to implement ABC on a 

particular project, the project managers are called on to 

organize and implement the project. In some cases, 

project planners have already determined the approach for 

the project (sometimes in conjunction with assistance from 

FHWA). In other cases, project managers are given the 

broad task of accelerating construction by any feasible 

means. 

In either case, this document can be useful to project 

managers in implementing specific methods or in the 

determination of the most appropriate forms of ABC. 

Chapter 3 of this manual includes significant information 

for project managers who are responsible for development 

of ABC projects.

1.1.1.3. Bridge Designers

Bridge Design engineers are asked to take the concepts 

that are developed in the project planning process and turn 

them into plans and specifications that are suitable for 

project bidding and construction. The previously published 

FHWA Manual entitled Manual on the Use of Self-Propelled 

Modular Transporters to Remove and Replace Bridges,

Publication Number FHWA-HIF-07-022, June 2007 [2] and 

Connection Details for Prefabricated Bridge Elements and 

Systems, Publication Number FHWA-IF-09-010, June 2007

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Federal Highway Administration Accelerated Bridge Construction Manual 

[3] are good sources of information and details that can be 

used in this process.

Other sources of design information can be found at a 

growing number of state agency websites. For instance, the 

Utah Department of Transportation has published design 

standards and manuals on the use of PBES for ABC 

projects. Other states such as Oregon, Washington, Texas 

and Massachusetts are also actively developing similar 

documents.

This manual can be used in conjunction with these other 

sources. When combined with sound engineering judgment, 

a successful ABC project can be developed and completed.

1.2. Why use Accelerated Bridge Construction?

During the development of the modern highway network, most bridge 

projects involved the construction of bridges for new highways. The 

construction work zones were typically open areas or “greenfields” with 

no traffic. Figure 1.2-1 shows a cast-in-place concrete bridge under 

construction in the 1930’s. The lack of traffic management allowed the 

use of shored formwork. These projects also involved large scale 

earthwork associated with the construction of the roadway. The 

construction process for the bridges in this scenario was not limited by 

adjacent traffic and was often not on the critical path for the overall 

construction of the highway.

The majority of the nation’s highway network is now complete. A large 

portion of this network has matured to the point where rehabilitation and 

reconstruction are necessary. Individual bridge replacement projects that 

Figure 1.2-1 Cast-In-Place Concrete Bridge Construction Techniques

57
Federal Highway Administration Accelerated Bridge Construction Manual 

are not part of an overall highway reconstruction are becoming more 

commonplace. This type of project brings the construction of the bridge 

to the critical path of the construction process. 

In most bridge replacement projects, vehicles traveling on the roadway 

need to be accommodated during the construction, which greatly 

complicates the design and construction process. This has been 

referred to as being analogous to replacing an engine’s oil while it is still 

running. Bridge designers and constructors have had to change the 

paradigm of bridge construction in order to account for this. Control of 

traffic (vehicular, bicycle and pedestrian) has become a significant 

portion of the overall construction process. This normally results in one 

of the following bridge construction scenarios:

• Relocation of traffic on a detour

This approach can have significant impact on the roads used for 

the detours, especially if the duration of the detour is significant. 

Traffic congestion is increased and safety is often compromised 

as the volume of vehicles traveling the detour increases. This 

approach also leads to increases in vehicle emissions, increases 

in noise pollution and accelerated deterioration of the road used 

for the detours. 

• Construction of a temporary bridge and bypass roadway

Temporary bridges are an effective means of freeing up space at 

the bridge site. This is often a preferred option to a detour; 

however it comes at a cost, both financial and physical. The 

construction of the temporary bridge and bypass approaches can 

represent a large portion of the overall project cost. This 

includes the cost for the installation and removal of the bypass. 

Temporary bridges may also require the acquisition of right-ofway and additional environmental permitting.

• Employ Stage Construction Techniques

This involves the construction of the bridge in portions or stages. 

Depending on the configuration of the bridge and the traffic 

volume, it may involve over-building the bridge in order to 

accommodate enough traffic lanes during construction. There is 

a cost implication to this approach; however the exact cost of 

construction staging is difficult to ascertain. Most bridge projects 

are bid on a unit cost basis or a lump sum basis. The cost of 

stage construction is included in the unit costs and cannot be 

easily separated from the actual cost of the materials. The 

general consensus of bridge engineers is that this cost is

significant. This may partially explain the reason why bridge 

construction costs are higher in the northeast and north central 

United States where the stage construction approach is 

common.

All of these scenarios have negative impacts on the overall construction 

process either through costs, safety to workers and the traveling public, 

impacts to the public, or impacts to the environment. Accelerated Bridge 

Construction using Prefabricated Bridge Elements and Systems can be 

used to address this paradigm shift in bridge construction. 

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Federal Highway Administration Accelerated Bridge Construction Manual 

ABC is not the answer for all projects. The impact of ABC on individual 

construction projects needs to be evaluated through the use of a 

decision making framework. The FHWA document entitled “DecisionMaking Framework for Prefabricated Bridge Elements and Systems 

(PBES)” [1] can be used to develop a consistent decision process. Other 

frameworks are in development and described in more detail in later 

sections.

The following section outlines the benefits that can be realized through 

the use of ABC in today’s infrastructure.

1.2.1. Benefits of ABC projects using PBES

There are a number of benefits that can be realized through the 

use of ABC with PBES. The following sections contain some of 

the more common benefits that have been experienced in different 

agencies.

1.2.1.1. Reduced Road User Impacts

Construction projects have a significant impact to highway 

users. Delays caused by construction congestion and 

detours result in loss of revenue to roadway users. Work 

zones are also cited as a significant risk factor contributing 

to roadway crashes. ABC can be used to reduce these 

impacts by shortening the duration of a project. 

The intent of transportation systems is to support mobility, 

not to infringe upon it. Not recognizing the travel delay and 

motorist and worker safety impacts caused by construction 

activities, or by accepting the status quo is doing a 

disservice to the traveling public. The FHWA Highways for 

Life Pilot Program, authorized by SAFETEA-LU, has 

challenged this notion. Through a combination of 

methods, the program has strived to create a culture 

change in the highway community to embrace innovation 

in ways that will improve service to America's drivers. ABC 

using PBES is a vanguard technology promoted by the 

program. 

ABC provides a balanced approach - cost versus impacts. 

There are tools available for DOTs to help decide on the 

balance that is right for each project. This manual provides 

an overview of these tools and makes reference to 

locations where agencies can look for in-depth information.

Road users are impacted by all forms of construction. 

Impacts can be significant, even if lanes are not affected 

by the actual work. For instance, on a busy highway that is 

flowing near capacity, a disabled vehicle in the shoulder 

can cause a significant back-up on the main line. Even in 

low volume roads, roadside activities can distract drivers 

59
Federal Highway Administration Accelerated Bridge Construction Manual 

and lead to accidents. Construction projects have a 

similar effect. Construction equipment working adjacent to 

travel lanes can have a negative effect on road users.

The definitions for ABC listed in the beginning of this 

manual identify the term “Mobility Impact Time”. This is 

any period of time the traffic flow of the transportation 

network is reduced due to onsite construction activities. 

Mobility impact time can be broken down into 5 tiers of 

potential impact:

Tier 1: Traffic Impacts within 1 to 24 hours

Tier 2: Traffic Impacts within 3 days

Tier 3: Traffic Impacts within 2 weeks

Tier 4: Traffic Impacts within 3 months

Tier 5: Traffic Impacts from 3 months to years

One of the goals of any ABC project is to move a project 

constructed with conventional methods from one tier to at 

least one higher tier. For instance, if a project build with 

conventional methods is estimated to take 6 months to 

build, the goal might be to reduce the mobility impact time 

to within 3 months. 

A reduction in mobility leads to increases in costs to 

society. Construction affects road users by increasing the 

time it takes to travel through a work zone. Road user 

costs are real; however they are not funds that can be 

applied to agency budgets. The funds used to finance 

construction project come from roadway users through 

taxes and/or tolls; therefore the impacts of roadway users 

should be identified and accounted for in the project 

planning process. Chapter 3 contains more information on 

how different agencies account for road user costs. 

Through documented case studies, the Highways for Life 

Pilot Program has demonstrated in several states that the 

cost of deploying ABC innovations is often outweighed by 

the cost avoidance/savings to the road users.

1.2.1.2. Improved Worker and Motorist Safety

Construction of a bridge along an active highway is usually 

a dangerous work zone. Workers are often performing 

their duties directly adjacent to active traffic. Every year, 

construction workers are killed in work zones, which makes 

work zone safety a primary focus of transportation 

agencies.

Motorist safety is affected by the change in the existing 

transportation network and the distractions caused by the 

on-site construction activity. Work zone traffic 

management layouts often maximize the lane volume of 

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Federal Highway Administration Accelerated Bridge Construction Manual 

traffic through a work zone. This leads to a higher 

potential for slow-downs and braking within the work zone. 

The inevitable result is rear-end accidents brought on by 

slowed or stopped vehicles and driver distraction. 

There are several ways to improve worker safety and 

motorist safety through the use of ABC. By reducing the 

amount of time that a project is actually in construction, the 

exposure of workers and motorists to potentially hazardous 

situations is reduced. The most significant way to improve 

worker safety is to remove traffic from the site via a shortterm detour combined with ABC. This greatly improves 

worker safety since no active traffic will be on the bridge 

site during construction. Use of PBES can be used to 

minimize the amount of labor at the site. Construction of 

large portions of the bridge in fabrication plants or staging 

areas can be done in a safer environment without the 

impacts of traffic.

1.2.1.3. Expedited Project Planning Process

The construction of a bridge project can result in significant 

impacts to utilities, right of way, and the environment 

(including air quality, water quality, noise, flora and fauna). 

Today, some projects are built with limitations placed on 

activities that occur over environmentally sensitive areas 

due to potential effects on various species. For instance, 

spawning of fish can lead to limitations on in-water work 

periods such as pile driving. These types of limitations can 

prolong the construction time for a project. It is not 

uncommon to have a construction site close down for 

months because of these necessary environmental

limitations. ABC can be used to minimize the time that a 

contractor is working in and around an environmentally 

sensitive area during allowable periods. This can reduce 

the duration of a project by months or even years for some 

projects if the work can be completed before the activity 

limitation period. These potential limitation timeframes 

should be evaluated during the project planning and 

scheduling process. ABC should be considered as a way 

to work within the limitation timeframe without have the 

project drag on for months or years due to inactivity at the 

construction site. 

In some cases, new roadway alignments are used to 

accommodate traffic during construction. ABC can allow 

for construction on the same alignment with a full roadway 

closure and a short duration detour. This will reduce the 

overall impact to the environment. This also has a 

beneficial effect on utility and right of way impacts. These 

reductions can benefit the project planning process. By 

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Federal Highway Administration Accelerated Bridge Construction Manual 

reducing impacts, the project can progress more quickly 

through the design development and environmental impact 

review processes. 

1.2.1.4. Improved Quality

The quality of on-site work has always been held to a high 

standard. Quality of construction is achieved by strict 

specifications and quality control procedures. Even with 

these controls, it can be challenging to construct a bridge 

to a high degree of quality given the harsh environments 

that work crews are exposed to. 

The quality of site cast concrete can be affected by 

temperature, humidity, rain and wind. These factors can 

reduce the durability of the concrete and lead to excessive 

cracking. Construction of steel structures can also present 

challenges as well. Field welding of steel in low 

temperatures can be very challenging and expensive. 

Prefabrication can offer a number of advantages when 

compared to on-site construction. Many prefabrication 

plants include indoor fabrication areas where the work can 

be removed from the elements. Outdoor fabrication areas 

can also be tented during extreme weather conditions. 

Prefabrication plants also have the luxury of construction 

without traffic. The workers and their work activity are 

taken off the critical path for on-site construction. Worker’s 

exposure to difficult and dangerous situations such as work 

zone traffic management and night time construction are 

also reduced. 

A significant benefit to prefabrication of concrete elements 

is the lack of restraint during the concrete curing process. 

Restraint of concrete occurs when a concrete pour is made 

adjacent to and connected to a previously poured element 

or fabricated element. Examples of this include concrete 

decks cast on top of girders and concrete walls cast on top 

of footings. The freshly placed concrete will shrink during 

curing; however the adjacent concrete or girder restrains 

the concrete from shrinking. This leads to a build-up of 

internal tensile stresses in the concrete that can lead to 

cracking during the cure. 

Prefabricated concrete elements have less potential for 

restraint cracking since the element is typically not cast 

against another element. The only restraint is the friction 

between the form and concrete. Historically, precast 

concrete elements have experienced significantly less 

cracking than site cast concretes. It is well known that 

cracking can lead to long-term deterioration; therefore, 

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Federal Highway Administration Accelerated Bridge Construction Manual 

reductions in cracking will have a positive effect on the 

long-term durability of the element.

Improvements to quality have an effect on the service life 

of the structure. Higher quality reduces the need for 

maintenance and extends the life span of the structure. 

This will lead to a reduced life cycle cost for prefabricated 

structures. This can be used to offset the potential 

increase in initial cost for ABC that is discussed in Section 

1.2.1.6.

An example of improved quality through the use of ABC

and PBES is a bridge built by the Connecticut DOT in 1990 

using a full-depth precast concrete deck panel system. 

The bridge is a six span curved structure that carries ramp 

traffic from Interstate 84 to Connecticut Route 8. The ramp 

was narrow; therefore stage construction was not viable. 

The ramp was closed and a detour was established. ABC 

was used to minimize the impact of the detour to the 

traveling public. The result of this approach was that the 

deck was replaced in 42 days using a system that included 

longitudinal post tensioning to join the individual deck 

panels. A waterproofing system combined with a 

bituminous overlay was used to provide added protection 

and a smooth riding surface. Figure 1.2.1.4-1 shows the 

deck under construction in1990.

The resulting structure has a crack free deck. The bridge is 

void of typical cracks that are found in virtually all cast-inplace concrete decks that are primarily caused by the 

restraint of the girders below. The deck has been in 

service for 20 years and it is still in excellent condition with 

no noticeable cracking. Based on its current condition, it is 

anticipated that the deck will have a service life that 

exceeds that of cast-in-place concrete decks. Section 

2.6.1.1 has more information on precast deck panels 

including present day photos of this Connecticut bridge 

after 20 years in service.

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Federal Highway Administration Accelerated Bridge Construction Manual 

Figure 1.2.1.4-1 Precast Deck Construction in 1990

1.2.1.5. Improved Constructability

Prefabricated elements can improve the constructability of 

a bridge, especially on sites that have significant 

constraints. The use of prefabricated bridge deck 

elements can be used to minimize or eliminate the need for 

workers to install and remove formwork. This can be 

especially beneficial for bridges over railroads, rivers, and 

high volume highways.

The use of prefabricated substructure elements can be 

advantageous for substructure that are located adjacent to 

traffic or rails, where there are strict time and space 

limitations around the elements. The use of prefabricated 

elements can allow the contractor to get in quickly and 

complete the construction within a limited timeframe.

1.2.1.6. Reduced Cost to Society

All infrastructure projects come at a cost to society; 

however the benefit of the completed project outweighs the 

cost for construction. The monetary costs of construction 

can be measured in two ways. The first is the actual 

construction cost of the project in tax dollars. The second 

is the monetary cost to society cause by delays during 

construction. The intent of ABC and PBES is to reduce 

construction time, thereby reducing the cost to society 

caused by delays. The ultimate goal of prefabrication is to 

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Federal Highway Administration Accelerated Bridge Construction Manual 

also reduce the construction cost through repetitive use 

and a shift of construction work from dangerous and 

congested work zones to safe and open prefabrication 

areas. 

Agencies that have completed initial ABC/PBES projects 

have seen increases in construction costs in the range of 

10% to 30% depending on the size and nature of the 

project. There is no general factor that can be applied to 

the costs for ABC/PBES. Some of the factors can have an 

impact on the overall construction costs for ABC include:

• Size of project

• Construction time limits including procurement time

• Need for specialized equipment

• Repetition of elements

• Repetition of similar projects

All of these factors can affect the construction cost for an 

ABC/PBES project. The following generalizations can be 

made for typical projects:

• For projects that are large and have significant 

repetition, the costs for ABC/PBES can actually be 

less than conventional construction. 

• Moderate sized projects with some repetition can be 

expected to cost between 10% and 20% more than 

conventional construction. 

• Smaller projects can be expected to cost between 

20% to 30% more than conventional construction. 

• Complex projects with very specialized requirements 

can have costs that exceed these values. 

FHWA is developing a “rule of thumb” guideline for 

calculating ABC costs for various projects entitled “Work 

Zone Road User Costs”. This will be available in the near 

future on the FHWA ABC website. 

While the unit price of prefabricated bridge elements can 

be higher than conventional construction, there are other 

ways that prefabrication can be used to reduce overall 

project costs. Any reduction in construction time can 

results in lower agency costs and lower maintenance of 

traffic costs. Chapter 3 has more information on how to 

reduce costs with ABC and PBES. 

As with implementation of any new technology, initial costs 

can be significant. This is due to many factors, some of 

which include:

• Purchase of equipment or formwork

• Cost of training for staff

• Unfamiliarity of the process 

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Federal Highway Administration Accelerated Bridge Construction Manual 

• Risk

Many of these factors can be reduced simply by building a 

series of projects versus construction of just one 

prefabricated bridge. Equipment and formwork can be reused or amortized over multiple projects. Staff will become 

more experienced with the process, which will lead to 

reduced risk. 

Long-term use of any new technology has historically led 

to lower construction costs. The best example in the 

bridge construction market is the introduction and 

development of prestressed concrete. Early uses of 

prestressed concrete were undoubtedly more expensive 

than site cast concrete. Over time, with increased use, the 

cost of prestressed concrete has decreased to the point 

that it is significantly lower than site cast concrete in most 

situations.

Minor increases in construction costs associated with ABC 

can be justified in several ways. The increase in quality 

discussed in Section 1.2.1.4 can lead to lower life cycle 

costs. The reduction in road user costs can also be 

accounted for in the project development process. Road 

user costs are not dollars that can be spent on the project; 

however they are real dollars to the traveling public, who 

are the financial supporters of the project through their 

taxes. 

1.2.2. Positive Public Perception of ABC

The impacts of a construction project on the traveling public are 

significant. ABC can reduce these impacts, which results in a 

tremendous positive perception of the construction process and 

the agency. Public perception and user impacts are very 

important, since the public are the customers of the agency that is 

building the project, and they are the ones paying for product. In 

many locations, the public is resigned to the fact that bridge 

construction projects take a long time. The delays caused by the 

construction are a necessary burden that comes with the process. 

Agencies can receive intense criticism for projects that seem to go 

on forever. This does not need to be the case. ABC can be used 

to present a more positive view of bridge construction. 

1.2.2.1. Public Response to ABC Projects 

The Utah Department of Transportation undertook an ABC 

initiative that was the most ambitious program in the United 

States. Starting with the build-up for the 2002 Olympics, 

they worked toward considering ABC for all bridge 

projects. They have developed standards, manuals and 

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specifications for all forms of ABC. To date, they have built 

hundreds of bridges using ABC techniques.

Part of this process includes the measurement of success. 

The department routinely measures public perception of 

construction projects through the use of post-construction 

questionnaires. Following a typical construction project, 

stakeholders are asked to rate their overall satisfaction 

with the project results. Responses to most projects break 

down into three roughly equal categories. 

• One third of the respondents are satisfied

• One third are not satisfied

• One third are indifferent 

One can surmise that the satisfied respondents are simply 

happy to see an improvement in the facility regardless of 

the time for construction. The other respondents are 

clearly not satisfied with the project as a whole.

A Likert 7-point polling process was done for a project that 

used ABC techniques. The results of this polling are 

depicted in Figure 1.2.2.1-1. The results of this poll are 

quite different from the typical construction project in Utah. 

Over 94 percent of the respondents rated the project with a 

score or 6 or 7 (out of 7), and over 97 percent of the 

respondents rated the project as a success. In addition, 

no respondents rated the project less than 3.

The overwhelmingly positive perception of ABC projects 

was not lost on the decision makers of the State. This data 

was used by the department of transportation to 

demonstrate the benefits of ABC to the State legislature. 

Even in a time of fiscal restraint, the legislature of Utah 

continued to fund the transportation program at a higher 

level than in previous years. 

Other states have completed user satisfaction polling and 

found similar responses. The general response is 

satisfaction with the reduction in onsite construction time 

and mobility impact times.

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Federal Highway Administration Accelerated Bridge Construction Manual 

One of the performance goals a construction project should strive 

to satisfy in order to be granted incentive funding from the 

Highways for Life program is achieving a score of 4+ on a 7-point 

Likert scale for user satisfaction. Several highway agencies that 

have been recipients of grant funding under this program have 

achieved these scores and intend to sustain the user satisfaction 

levels on future projects. Examples of notable ABC demonstration 

projects funded by the program that have documented user 

satisfaction surveys include those from Georgia, Oregon, and 

Utah. Project summaries from these projects can be found from 

the program’s website: 

http://www.fhwa.dot.gov/hfl/summary/projects_summary.cfm.

Figure 1.2.2.1-1 Sample Public Satisfaction Poll in Utah

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Federal Highway Administration Accelerated Bridge Construction Manual 

Chapter 2 Accelerated Bridge Construction Technologies

This chapter will focus on the various technologies that are employed for ABC projects, 

the processes and provisions, and how they are applicable to various types of bridge 

construction projects.

There is no one ABC technique in use in the United States. Instead, there is a family of 

ABC construction and contracting technologies that are in use that cover the majority of 

ABC projects. Figure 2-1 shows the most common forms of ABC technologies in use 

today as compiled by the Federal Highway Administration as part of the “Every Day 

Counts” initiative. This effort is being used to encourage innovation in construction in 

order to reduce impacts to the traveling public. The foundation and wall element 

technologies and rapid embankment construction technology are in the early stages of 

deployment, while others are mature and in use on a regular basis. It is notable that 

some of the construction practices support bridge construction, but are not strictly bridge 

elements. The innovative contracting techniques work synergistically with ABC, as well 

as other types of construction. 

Figure 2-1 Accelerated Bridge Construction Technologies

source: FHWA Every Day Counts Initiative)

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Federal Highway Administration Accelerated Bridge Construction Manual 

2.1. Foundation and Wall Elements

2.1.1. Continuous Flight Auger Piles 

(CFA)

This is method of constructing a 

deep foundation element using a 

simplified continuous process. 

CFA piles are sometimes referred 

to as Augered Cast-In-Place 

(ACIP) piles, drilled displacement 

piles, and screw piles. 

Normally, drill shafts require 

several distinct processes. First, 

the shaft is drilled using an auger or rock coring device. The 

materials within the pile bore hole are removed. Following this, 

reinforcement is placed in the hole and the voids are filled with 

concrete. 

Continuous flight auger piles methods combine several of these 

processes into essentially one process. Figure 2.1.1-1 depicts a 

graphical representation of a CFA pile installation. In process “a”, 

a soil auger is drilled into the ground in a continuous stroke. Once 

the proper depth is achieved, the auger is withdrawn from the soil 

in the hole, while continuously injecting concrete through the 

hollow stem of the auger. This process is labeled “b” in the figure. 

Once the auger has been withdrawn from the hole, a reinforcing 

cage is inserted into the wet concrete to complete the installation. 

This process is labeled “c” in the figure. 

Figure 2.1.1-1 Continuous Flight Auger Pile Installation

(source: Bauer Maschinen) 

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Federal Highway Administration Accelerated Bridge Construction Manual 

By combining these processes, the time for foundation installation 

can be reduced. More information on this subject can be obtained 

in the FHWA Geotechnical Engineering Circular (GEC) No. 8

entitled “Design and Construction of Continuous Flight Auger 

Piles” [5].

2.1.2. Geosynthetic Reinforced Soil Integrated Bridge System 

(GRS/IBS)

This method of foundation installation involves combining the 

foundation, abutment and approach embankment into one 

composite material. The structure below the superstructure is 

comprised of multiple thin layers of soil and geosynthetic 

reinforcement. The internal soil is retained at the face of the 

abutment with a high quality concrete block facing. The facing is 

not a structural element of the system. It simply retains and 

prevents erosion of the soil near the face of the wall. The 

composite mass extends beyond the ends of the bridge 

superstructure and into the embankment. This integration of the 

abutment with the superstructure and approach allows the system 

to move and settle as one unit, thereby eliminating the problem 

with differential settlement between the abutment seat and the 

approach backfill. This differential settlement often leads to a 

bump at the end of the bridge. The integrated bridge system does 

not require approach slabs to span across the potential bump.

The superstructure typically sits on top of the GRS fill without

bearings. The superstructure loads, rotations, and movements 

are carried directly by the GRS system. The system can be used 

with precast butted box beams, precast slabs, or with conventional 

stringer deck systems. With stringer bridges, a small footing

combined with an integral pour is used to seat the superstructure 

on the GRS embankment. Figure 2.1.2-1 depicts a typical section 

of a GRS/IBS bridge abutment.

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The benefits of this system include:

• Low initial cost

• Low life cycle cost

• Fast construction (under 30 days for most bridges)

• Minimal installation labor and equipment

• Eliminates the need for approach slabs

The limitations of this system include:

• Span lengths are currently limited to spans less than 140 

feet (until more data on longer span bridges is compiled).

• The system is not appropriate for locations where scour 

would prevent the use of shallow foundations.

• It is currently only recommended for single span bridges, 

however multi-span bridges are being considered.

Even with these limitations, the GRS/IBS system could potentially 

be used for a large number of the single span bridge inventory, 

including the large number of rural county bridges in the United 

States. More information on this subject can be obtained at the 

FHWA website: www.fhwa.dot.gov/everydaycounts. A GRS/IBS 

implementation guide is also available at the FHWA website: 

Figure 2.1.2-1 Typical Section of a GRS/IBS Bridge Abutment 

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www.fhwa.dot.gov/publications/research/infrastructure/structures/11026/i

ndex.cfm.

2.1.3. Prefabricated Pier Cofferdams

Construction of deep foundations in deep water is a daunting 

challenge. Several methods have been developed for cofferdams 

including driven steel sheeting and framing systems combined 

with underwater tremie concrete. The advent of large diameter 

piles and drilled shafts has reduced the need for deep concrete 

pours that were traditionally placed below the mud line. Today, it 

is becoming more common to perch the bottom of the pile cap 

footing just below the water surface. 

Prefabrication can be used to facilitate the casting of the pile cap 

footing. Pier box forms have been developed that can be floated 

into position and hung from the piles or drilled shafts. In some 

cases, the forms can be ballasted into position using buoyancy to 

support the wet concrete. The pier boxes can be fabricated with 

steel and removed after casting, or be fabricated with precast 

concrete and left in place.

2.2. Rapid Embankment Construction

2.2.1. Expanded Polystyrene (EPS) 

Geofoam

EPS Geofoam is an embankment 

fill system that is comprised of 

large blocks of expanded 

polystyrene. Unlike the GRS/IBS 

system, it is not intended to be a 

structural support system for the 

bridge abutment. The EPS 

blocks can be placed behind a 

conventional abutment or around 

the piles of an integral abutment.

Figure 2.2.1-1 is a photograph of a typical EPS Geofoam 

embankment prior to placement of the roadway structure and side 

slopes.

The benefits of this system include:

• Fast construction

• Extremely lightweight (1-2 pounds per cubic foot)

• Eliminates or reduces pre-load settlement times

The design considerations for this system include:

• A layer of subbase is required below the pavement to 

distribute wheel loads.

• Protection of the foam blocks from gasoline spills.

• The system should not be used where the water table will 

be above the bottom of the EPC blocks, which would 

cause uplift forces. 

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The lightweight nature of this material makes it ideal for areas 

where long-term settlement potential is high. The embankment 

weight can be reduced by a factor of up to 100, which will greatly 

reduce the amount of long-term settlement and the need for 

embankment pre-load time. More information on this subject can 

be obtained at the FHWA website: 

www.fhwa.dot.gov/engineering/geotech/improvement.

Figure 2.2.1-1 EPS Geofoam Embankment

(source ACH Foam Technologies)

2.2.2. Accelerated Embankment Preload Techniques

Establishment of embankments over soils that are subject to longterm settlement such as clays can lead to a long-term construction 

process. Often, preloads are applied to the embankments to 

accelerate the settlement of the sub-soils prior to roadway 

construction. Preload areas are often required to be left in place 

for many months and in some cases more than a year. 

Technologies are available to accelerate the settlement of the 

sub-soils. The goal of a preload system is to remove water from 

underlying clays in order to consolidate the layers. Stone columns 

and wick drains have been used to accelerate the removal of the 

water. This approach can reduce pre-load times by a factor of 

four or more.

2.2.3. Column Supported Embankment Techniques 

Another method of constructing embankments over compressible 

soils is to build a soil structure over the existing compressible subsoils. This can involve the installation of closely spaced piles or 

stone columns that are installed through the compressible soils. 

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Once in place, multiple layers of geosynthetic reinforced soils can 

be placed over the columns to produce a structural soil layer that 

can be used to support the new embankment. This method 

eliminates the need for time consuming pre-load of compressible 

soils. 

2.3. Prefabricated Bridge Elements and Systems

2.3.1. Prefabricated Elements

The most common form of 

ABC is the use of 

prefabricated bridge elements. 

These elements can be 

fabricated in a controlled 

environment off site and 

assembled in place at the 

bridge site. This construction 

method can best be described 

as building blocks. The 

prefabricated elements are 

connected at the site to form a 

complete bridge. 

Prefabrication of beams is not a new concept. Virtually all bridges 

are currently built with prefabricated beams and girders. Other 

industries have used prefabrication to speed project delivery and 

lessen cost. Industries such as parking structure have taken 

prefabrication to the highest levels. The newer concepts that are 

now finding more widespread use are prefabrication of the other 

elements on a typical bridge, such as bridge decks and 

prefabricated substructure elements (including pier columns, 

footings, and abutment/retaining wall stems and footings). 

Installation of prefabricated elements is normally completed using 

standard cranes.

Prefabricated construction requires joints between elements. 

There has been concern expressed by some agencies regarding 

the durability and structural integrity of the joints. Connection 

joints between elements are not only found in prefabricated 

construction. Conventional cast-in-place concrete construction 

includes many connections and joints. Cast-in-place construction 

is not normally monolithic. For example, there are construction 

joints between footings and columns and construction joints 

between columns and pier caps in open frame pier bents. There 

are even construction joints in bridge decks on multi-span bridges. 

These construction joints are required in order to facilitate the 

forming and placement of concrete and to reduce cracking 

brought on by shrinkage of concrete and deflection of structures.

The approach to connecting prefabricated elements is to replace 

construction joints with precast connections. The term “emulation 

design” was applied to this approach by the American Concrete 

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Institute (ACI). ACI in conjunction with the American Society of 

Civil Engineers (ASCE) have published a report entitled 

“Emulating Cast-in-place Detailing in Precast Concrete Structures” 

[6]. This report recommends various connections for 

prefabricated elements. The connections include small closure 

pours, grouted tubes with reinforcing dowels, welded ties and 

mechanical couplers. Many of these connections have been 

tested for structural capacity, seismic capacity, and long-term 

durability in other markets. The transportation market has been 

slow to adopt these solutions.

The FHWA manual entitled “Connection Details for prefabricated 

bridge Elements and Systems” [3] contains significant information 

for various prefabricated element connections. The durability of 

these connections has also been proven. The FHWA manual 

provides many examples of durable connections. For example; 

precast bridge decks panels that have been in service in a 

northern environment for over 20 years and precast bridge piers 

that have been in service in a highly corrosive environment for 

over 15 years. There are also on-going research projects in 

several research institutions that are looking into the durability of 

prefabricated connections. Preliminary results indicate that these 

connections can be both structurally sound and highly durable. 

Chapter 8 includes more information on the durability of 

prefabricated elements and connections.

Examples of prefabricated substructure elements are shown in 

Figure 2.3.1-1 (precast concrete cantilever abutment) and Figure 

2.3.1-2 (precast concrete open frame pier bent). These graphical 

representations are based on details developed by the PCI 

Northeast Bridge Technical Committee. Similar details have also 

been used in Florida, Georgia, Utah, and New Hampshire. In 

these structures, all elements are made with precast concrete. 

 

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Federal Highway Administration Accelerated Bridge Construction Manual 

Figure 2.3.1-1 Prefabricated Cantilever Abutment

Figure 2.3.1-2 Prefabricated Open Frame Pier Bent

Modular bridge elements are prefabricated elements that

represent a more significant portion of the finished structure. They 

are typically larger elements that are made up of several smaller 

components that are joined during prefabrication. An example of 

a modular element is two beams with a composite concrete deck 

cast in the fabrication shop or staging area. Installation of

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Federal Highway Administration Accelerated Bridge Construction Manual 

modular elements is similar to prefabricated elements. The crane 

sizes can get quite large because the modular elements are 

typically heavier than smaller elements. 

There have been several successful projects built using modular 

bridge technology. The most notable was the James River Bridge 

in Richmond Virginia. The superstructure of this viaduct bridge 

was replaced using only nighttime closures. The superstructure 

was prefabricated using multi-beam modules that were 

constructed with steel stringers and pre-topped concrete deck. 

The old bridge was removed in pieces using cranes, and new 

modular units were installed using the same equipment. Figure 

2.3.1-3 shows a new module being installed on the project. 

igure 2.3.1-3 Modular Steel Superstructure Element Installation

James River Bridge, Richmond, VA

Figure 2.3.1-4 shows a concept that was developed by the 

Massachusetts DOT for the replacement of bridge superstructures 

on Interstate 93 in Medford, Massachusetts. This project involved 

the replacement of 41 bridge spans in 10 weekends. The concept 

involved the complete closure of one side of the highway on 

weekends to create a 55 hour work window for the contractor to 

install the modules. Traffic was maintained on the opposite side 

of the interstate via two cross-overs that were constructed at each 

end of the project. 

F

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Federal Highway Administration Accelerated Bridge Construction Manual 

Figure 2.3.1-5 I-93 Superstructure Replacement Construction

Figure 2.3.1-4 I-93 Superstructure Replacement Concept

Figure 2.3.1-5 shows the actual construction in progress. Up to 6 

spans per weekend were replaced using this concept.

These are just some examples of how prefabricated elements can 

be used to construct bridges using details that are similar to cast79
Federal Highway Administration Accelerated Bridge Construction Manual 

in-place concrete. This has been referred to as “reverse

engineering the bridge”, or “emulation design”. The goal is to 

build bridges that are similar to proven design using precast 

concrete in place of cast-in-place concrete. 

2.3.2. Prefabricated Systems

It is possible to fabricate larger portions of the bridge and move 

them into place at a later date. Examples of prefabricated 

systems include complete superstructures, superstructures with 

integral piers, or even complete bridges. Most work completed to 

date in the United States has been with prefabricated

superstructures although engineers are starting to investigate 

work completed in Europe that also included integral prefabricated 

substructures. A key component to large-scale prefabrication is 

the methods used to move and install the elements. Typical crane 

installations are not normally used due to the weight of the

systems. The following section describes methods used to install 

prefabricated systems. 

2.4. Structural Placement Methods

2.4.1. Self Propelled Modular 

Transporters (SPMTs)

There are families of high 

capacity, highly maneuverable 

transport trailers called Self 

Propelled Modular

Transporters (SPMTs) that are 

being used in the bridge 

industry. The term “self 

propelled” in the title describes 

the fact that these trailers do 

not need a tractor to push or 

pull them. The propulsion 

comes from an on-board 

hydraulic power pack that is connected to hydraulic drive motors 

on several of the axles. The term “modular” in the title describes 

the ability to connect the trailers longitudinally and transversely to 

form a larger transporter. The descriptions of various 

configurations are normally noted as “lines” of wheel sets. Figure 

2.4.1-1 depicts a sketch of several different configurations and the 

corresponding descriptions. Other larger configurations are also 

possible.

There are several manufacturers of SPMTs. All are similar but 

have somewhat differing capabilities. Some have 8 tires per line, 

and others have 4 tires per line. Some transporters have wheel 

sets that can rotate 360 degrees, and others have limited rotation 

capacity. The SPMT’s are highly maneuverable and can be 

moved and rotated in all three dimensional axes (vertical, 

transverse, and longitudinal). When the individual transporters 

are interconnected, they can be programmed to function as one 

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Federal Highway Administration Accelerated Bridge Construction Manual 

Figure 2.4.1-1 Sample Self Propelled Modular Transporter Configurations

unit. Rotation about the vertical axis can be programmed to pivot 

about any point in space.

The typical load capacity for SPMTs is approximately 50,000 

pounds per axle line. Some SPMTs can carry over 75,000 per 

axle line. When interconnected, the units can move several 

million pounds or more. They can also be laid out and configured 

to accommodate varying soil conditions if these axle loads are 

problematic. 

SPMTs have been used for many prefabricated bridge

installations. The Utah DOT installed over 20 bridges in a three 

year period. Installation times range from 2 hours to 8 hours 

depending on the complexity of the travel path and the geometry 

of the bridge. Figure 2.4.1-2 shows an SPMT bridge move in 

Utah. This bridge weighed several million pounds and was moved 

approximately 1 mile from a staging area to the bridge site. Figure 

2.4.1-3 shows a large SPMT bridge move in Providence Rhode 

Island. This bridge was transported from a shipping pier onto two 

large barges. Once on board, the bridge was moved to the 

construction site that was 12 miles away. The entire installation 

only took several days. The Providence Bridge weighed 

approximately 6 million pounds.

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Federal Highway Administration Accelerated Bridge Construction Manual 

Figure 2.4.1-2 SPMT Bridge Moves in Utah 

Figure 2.4.1-3 SPMT Bridge Move in Rhode Island 

The document entitled “Manual on Use of Self-Propelled Modular 

Transporters to Move Bridges” [1] is recommended for more 

information on these machines. 

Since the publication of the FHWA SPMT Manual, the use of 

SPMTs has increased. To date, approximately 30 bridges in 13 

states have been moved using SPMTs. The Utah DOT is 

considered a leader in the use of this equipment. They have 

published a manual entitled “SPMT Process Manual and Design 

Guide” [7]. This manual covers project scoping, the design of 

bridges using SPMTs, and contracting with SPMTs. Sample 

specifications are also included in this manual (included in 

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Federal Highway Administration Accelerated Bridge Construction Manual 

Appendix C of this manual). More information on the use of 

SPMTs can be found at the FHWA website:

http://www.fhwa.dot.gov/bridge/abc/introspmtmoves.cfm. 

Many agencies have expressed concern over the specialized 

nature of this work, and the ability of local contractors to use 

SPMTs. The increased use of SPMTs has spawned a number of 

specialized heavy lift companies that own and operate this 

equipment. On a recent project in Massachusetts, multiple firms 

were involved in the proposal phase of the project. 

To date, at least six SPMT Heavy Lift firms are operating in the 

United States. The Federal highway administration maintains a 

listing of the ever growing number of SPMT suppliers. These 

firms cover the entire country; therefore this equipment is 

available to all state agencies. This increase in activity has also 

resulted in a reduction in the cost of the equipment. There is 

competition in the market, and costs have been significantly 

reduced. 

Determination of the cost of an SPMT bridge move is not a simple 

matter. There are various factors that can affect the overall cost 

of the move. The following are several major factors:

• Size of the bridge being moved

The number of SPMT Lines required for the move

Size of framing required to support the bridge over 

the SPMTs 

• Length and geometry of the travel path

Required turning movements

Transverse and longitudinal slopes requiring 

special leveling systems or temporary fill

• Engineering Costs

Requirements for lift calculations 

Design of framing between the SPMT and the 

bridge

• Quality of the supporting soil on the travel path 

Need for structural fill and/or steel plating

• Monitoring

Requirements for monitoring during the move

• Length of time that the equipment needs to be on site 

Multiple stages

Idle time of equipment

• Number of projects in the area

The opportunities to use equipment on more than 

one project during a given timeframe

Agencies are encouraged to review the documents previously 

noted and to contact SPMT heavy lift contractors to explore the 

actual costs for a specific project. The agency should be armed 

with answers to at least some of the factors noted above. 

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The time required to complete an SPMT bridge move varies 

depending on the complexities of the project. Superstructures 

have been installed in several hours (minus the connection to the 

approach roadways). Utah DOT has completed two 

superstructure replacements, including approach roadway 

connections in less than 24 hours.

2.4.2. Longitudinal Launching

Launching of superstructures has been used for many years for 

bridges over terrain that is inaccessible for cranes. Longitudinal 

launching involves erection of the bridge superstructure in a 

launching pit located behind one or both of the abutments. A 

lightweight launching nose is often used to minimize the deflection 

of the cantilevered end of the superstructure during the launching 

and to account for the defection of the end of the bridge as it 

reaches each support. In some cases, intermediate towers are 

used to minimize deflections on longer spans. 

Once the superstructure erection is complete in the launching pit, 

it is jacked horizontally out over the spans using a sliding or rolling 

system. 

Launching has been used for both steel and concrete structures. 

It has also been used on curved structures. Launching can be 

relatively faster than other methods of construction at difficult 

sites; therefore it warrants consideration. 

One example of an appropriate use of launching is a bridge over a 

deep gorge. The cost and size of cranes in a deep valley can be 

large. It may not even be possible to set elements in certain 

situations. One method that has been used is segmental 

construction using balanced cantilever construction, launching 

should be considered as another option. 

Another example is the construction of a bridge over a busy 

navigation channel. Launching methods can eliminate the need 

for delivery of elements by barge that may tie up the navigation 

channel for periods of time. The access limitations in the channel 

may significantly increase the time required to construct the span. 

Launching can be used to eliminate the need for work within the 

channel and thereby expedite the construction process. More 

information on longitudinal launching can be found in an NCHRP 

report entitled “Bridge Construction Practices using Incremental 

Launching” [61].

Figure 2.4.2-1 shows a longitudinal launch of a bridge in Utah. 

The superstructure was delivered to the site using SPMTs 

traveling on the widened interstate roadway. Once at the bridge 

site, the superstructure was transferred onto a launching frame. 

This installation was completed in approximately 3 days.

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Federal Highway Administration Accelerated Bridge Construction Manual 

Figure 2.4.2-1 Longitudinal Launching of a Utah Bridge

(source: Utah DOT) 

The time required to complete a longitudinal launch varies 

depending on the size of the bridge and the available room for a 

launching pit. The procedure can typically take between several 

days and several months. 

2.4.3. Horizontal Skidding or Sliding

Another method of moving and installing large bridge systems is 

called lateral sliding/skidding. This method requires that the new 

bridge be built in parallel to the proposed finished location. The 

structure is normally built on a temporary support frame that is 

equipped with rails. The bridge can be moved transversely using 

cables or hydraulic systems. Minor vertical adjustment can also 

be incorporated into these systems. Figure 2.4.3-1 shows a 

lateral slide of a single span bridge in Utah. 

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There are several approaches that can be used for this method. 

The first and most common, is to build the new bridge along the 

side the existing bridge. Once the new bridge is complete, the old 

bridge is demolished, the new substructures are installed (if 

required), and the new bridge is slid into place. Another method is 

to build the new substructures under the old bridge prior to the 

move. Once complete, the old bridge is slid out of the way, and 

the new bridge is installed immediately. Figure 2.4.3-2 shows a 

lateral slide of a multi-span bridge in Oregon that demonstrates 

this process. The new bridge is located on right, and the old 

bridge, which has already been moved out of place is on the left. 

This project was a FHWA Highways for LIFE demonstration 

project. More information on this project can be obtained at the 

FHWA Highways for Life website: 

www.fhwa.dot.gov/hfl/summary/projects_summary.cfm.

Figure 2.4.3-1 Lateral Bridge Slide in Utah

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Figure 2.4.3-2 Lateral Bridge Slide in Oregon

Innovative foundations can be incorporated into this process. 

Foundations that include drilled shafts placed outboard of the 

existing bridge have been combined with transverse cap beams to 

allow for construction of the new substructure under the existing 

bridge. On several bridges in Utah, the cap beam was integrated 

into the new bridge superstructure. This approach eliminates the 

need to build the substructures after the removal of the existing 

bridge. The use of prefabricated substructure elements can also 

be used to reduce the amount of time between the demolition of 

the existing bridge and the lateral slide-in.

One of the most dramatic examples of a lateral slide-in is a project 

that was completed in California on the Oakland Bay Bridge. The 

slide-in was required to connect the new approach structure 

temporarily to the existing main span, thereby making room for the 

construction of a portion of the new bridge in the area. Once that 

span is complete, another lateral slide-in will be used to make the 

final connection to the new main span. Figure 2.4.3-2 shows the 

lateral slide in progress. In the photo, the old bridge has already 

been moved (to the left), and sliding of the new bridge is about to 

commence (to the right). The bridge is a multi-level through truss. 

The lateral slide of this bridge occurred during a three day 

weekend closure.

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Federal Highway Administration Accelerated Bridge Construction Manual 

Figure 2.4.3-3 Lateral Bridge Slide of the Oakland Bay Bridge Approach

(source: Mammoet) 

Another approach that has been used involves the use of the 

existing bridge as a temporary bridge on a temporary alignment. 

The existing bridge is slide laterally onto temporary supports that 

are adjacent to the bridge. In this scenario, the old bridge is used 

as a temporary bridge, while the new structure is built along the 

final alignment. This saves the cost of designing, erection and 

removal of a temporary bridge superstructure.

The time required to complete a lateral slide-in varies depending 

on the size and complexity of the bridge. Typical replacement of 

single and multiple spans have been completed during weekend 

closures. 

2.4.4. Other Heavy Lifting Equipment and Methods

Large-scale elements can also be installed using vertical lifting 

machinery. The most common types of equipment are strand 

jacks and climbing jacks. The difference between these two 

systems is that strand jacks pull the elements up vertically using 

cables and the climbing jacks push the elements using hydraulics. 

These systems can lift a large structure incrementally. Strand 

Jacks can be used to lift large structures over waterway crossings 

where the structure can be shipped to the site via barge. 

Figure 2.4.4-1 depicts a strand jack lift of the Providence River 

Bridge in Rhode Island. The original design called for erection of 

the arch on false work over a navigation channel. The contractor 

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chose an alternate method of construction where the bridge would 

be assembled 12 miles from the construction site on a shipping 

pier. This allowed the construction of the superstructure to occur 

in parallel with the construction of the foundations and 

substructures. The network arch bridge was erected at ground 

level, where the majority of the field bolting took place. The 

bolting at ground level saved months of erection time when 

compared to higher level piece work on staging. Strand Jacks 

were used to lift the completed structure to its final elevation. The 

structure was then transferred to SPMTs, and then transferred to 

two large barges for final transport to the bridge site. This method 

of construction saved approximately 1 year in construction. 

Significant disruption of the river channel was limited to one day.

Figure 2.4.4-1 Strand Jack Lifting of the Providence River Bridge

(source: Mammoet) 

Another less common method of prefabricating and installing a 

bridge is pivoting. This method involved rotating the prefabricated 

bridge into its final position in either the vertical or transverse 

bridge axis. Vertical axis pivoting can be used for waterway and 

railroad crossings. The structure can be built alongside the 

feature that is to be crossed and rotated into its final position. 

Figure 2.4.4-2 shows transverse pivoting of a new pedestrian 

bridge in Meylan, France. Transverse axis pivoting has been 

used to erect arch bridges by installing the elements in the vertical 

position at the supports and rotating them into position with cables

(similar to a bascule bridge closing). 

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Federal Highway Administration Accelerated Bridge Construction Manual 

Figure 2.4.4-2 Vertical Axis Pivot Technique

Meylan Pedestrian Bridge, France 

Other innovative erection methods have been developed to install 

prefabricated elements on various bridges. Gantry cranes are 

finding more use on ABC projects. There are several 

configurations that have been used. The first is a transverse 

gantry crane. Figure 2.4.4-3 is a sketch of a gantry crane 

supported on a temporary trestle. Once installed, the crane can 

access all portions of the bridge site. During peak traffic hours, 

the crane can be left in place, allowing traffic to pass beneath. 

This type of system has been used on long span suspension 

bridge, where the gantry support rails were placed on the fascia 

stiffening truss.

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Federal Highway Administration Accelerated Bridge Construction Manual 

Figure 2.4.4-3 Transverse Gantry Crane Installation Technique 

Another type of gantry systems is a longitudinal gantry frame. The 

Washington State DOT completed the re-decking of the Lewis and 

Clark Bridge using this technology. The project involved the 

replacement of the deck on a long-span through truss. An 

innovative gantry crane system combined with SPMTs was used 

to remove existing modules and install the new modules in one 

procedure. The gantry frame was designed to fit within the truss 

framing, and it was designed to carry both the old deck/stringers

and the new module. Figure 2.4.4-4 shows the gantry system that 

was used on the Lewis and Clark Bridge. This system allowed the 

removal and replacement of deck/stringer modules in an overnight 

operation.

Figure 2.4.4-4 Delivery of Modular Unit using a Gantry Frame 

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Federal Highway Administration Accelerated Bridge Construction Manual 

Figure 2.4.4-5 is a graphical representation of how the gantry 

frame system could be used on bridge. The longitudinal gantry 

frame method of installation is limited to relatively short span 

bridges because the size of the frame needs to be more than 

twice the length of the modules being installed.

Large overhead longitudinal gantry cranes are used on segmental 

bridge construction to build over areas that are inaccessible to 

conventional construction equipment. This includes 

environmentally sensitive wetland, busy highways and river 

channels. These systems can be used to install piling, drilled 

shafts, segmental superstructures, and total bridge systems. 

Longitudinal gantry cranes can save significant time on difficult 

construction sites.

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Federal Highway Administration Accelerated Bridge Construction Manual 

Delivery of New module and Removal of Portion of Bridge using the Gantry 

Frame

Installation of new Module using the Gantry Frame

 

Figure 2.4.4-5 Longitudinal Gantry Frame Installation Technique 

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2.4.5. Conventional Cranes

Many prefabricated elements can be installed using conventional 

cranes. Cranes are an integral part of most bridge construction 

projects. The erection of beams and girders are the primary use 

for cranes. It is possible in many cases to design prefabricated 

elements to be approximately the same weight as the girders. In 

this scenario, the same cranes can potentially be used for the 

erection of the prefabricated elements and the girders. Figure 

2.4.5-1 shows the installation of a prefabricated deck panel with a 

crane.

 

Figure 2.4.5-1 Precast Deck Panel Installation using Cranes

(source: Utah DOT) 

Modular systems can also be installed using cranes. The larger 

weight of the elements may require the use of multiple cranes at 

bridge site (similar to erection of large girders). Figure 2.4.5-

shows a scenario for the erection of modular elements usin

conventional cranes. Four cranes are shown. The center tw

cranes are used for erection of the center span. The crane

behind the abutments could work with one of the center cranes t

erect the end span modules.

Modern High Capacity Hydraulic Cranes have been developed f

use in heavy lift projects. These cranes are available in the Unite

States. They can travel over the road and be set up in a sho

amount of time (1-2 hours). Crawler Cranes are also available f

heavy lift operations. Lifts of approximately 150,000 pound

picked at a radius of 100 feet are attainable using this type 

equipment. Larger loads may also be feasible with shorter pic

radii. Designers should investigate the feasibility of cranes at 

a 

2 

g 

o 

s 

o 

or 

d 

rt 

or 

s 

of 

k 

a 

site by checking availability with local crane companies, 

establishing set-up locations, locations for delivery trucks and 

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Federal Highway Administration Accelerated Bridge Construction Manual 

capacity of underlying soils and structures to accommodate the 

crane loads. 

Figure 2.4.5-2 Modular Element Installation using Cranes

2.5. Fast Track Contracting

The previous sections focus on 

methods which are typically used to 

accelerated on-site bridge 

construction. This section will 

discuss other methods that are used 

to Accelerate Bridge Construction 

during the planning stages using 

Contracting Processes, and by the 

use of contracting language using 

Contracting Provisions. 

There are two major forms of 

accelerating the construction of a 

bridge. The first is accelerating the actual construction of the bridge in 

the field. The previous sections focus on the typical methods in use. 

The goal is to minimize the impacts of the construction on the traveling 

public and surrounding communities. In many cases, the design of the 

project can be carefully planned and designed. In construction, the 

fabrication of elements can also be completed prior to roadway closures 

with no impact to the public. Once the fabrication is complete, the 

project can be completed quickly. 

The second way to accelerate the construction of a project is to reduce 

the time required to plan, design, and bid the project. This is referred to 

as Accelerated Project Delivery (APD). Another key component to 

accelerating construction is through the use of contracting provisions that 

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place emphasis on the need to complete the project quickly. The 

following sections explore these concepts in more detail.

2.5.1. Accelerated Project Delivery

Accelerated Project Delivery (APD) is used to expedite projects for 

various reasons. An extreme situation, such as a closure of a 

bridge due to deterioration, would warrant an APD approach. 

Other scenarios would include bridges damaged by vehicle 

impacts, ship impacts, floods, or seismic events. The use of APD 

is also increasing as States feel political and economic pressures

to expedite projects. Accelerated project delivery can be 

combined with ABC to get these critical projects open to traffic in a 

short period of time.

APD can take several forms, but the most commonly used forms, 

have consisted of methods that shorten the design and 

construction times in project delivery. These methods take 

advantage of the idea that design and construction can take place 

concurrently with certain types of innovative contracting. This 

differs from the widespread traditional practice of Design-Bid-Build

(DBB), which requires design and construction to take place 

sequentially. Innovative contracting is characterized by early 

contractor involvement and input into design decisions, and by 

initiation of construction prior to design completion.

Innovative contracting is a natural fit for accelerated bridge 

construction. Often, there are multiple methods of construction 

that are feasible for a particular bridge site, each with its own 

requirements for equipment. The ability to have the construction 

contractor involved in the design process can be a valuable tool 

for innovative projects. In these situations, the contractor’s input 

can play a significant role in the design options that are examined. 

The design can also be tailored to the equipment that the 

contractor has access to.

FHWA has established a project entitled Special Experimental 

Project Number 14 (SEP-14) - Innovative Contracting. This was 

developed to enable state transportation agencies the ability to 

test and evaluate a variety of alternative project contracting 

methods. The goal is to expedite highway projects in a more costeffective manner, without jeopardizing product quality or 

contractor profitability. 

Two common innovative contracting methods of APD that are in 

use on ABC projects are “Design/Build” and “Construction 

Manager General Contractor”. The following sections describe 

these two processes, including their similarities and differences:

 

2.5.1.1. Design-Build (DB)

Design-Build is a project delivery tool that combines the 

expertise of the design engineer with the expertise of the 

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contractor in one team and in one contract. With this 

method the owner relinquishes control of the design and 

construction process and decisions to the Design-Builder. 

In this method it is important that the owner can articulate 

and convey their performance expectations of the final 

project to the Design-Builder. Many agencies are using 

Design-Build to expedite project delivery. Each agency 

has specific approaches to this process; however there are 

commonalities.

The DB process combines the design and construction 

processes into one contract. Contractors team with design 

engineers to design and build a particular project. A 

certain amount of up-front design is normally completed by 

the agency prior to bidding a DB project. This often 

involves preliminary design, acquisition of right of way, and 

procurement of environmental permits. The DB process 

requires that the owner properly define the fundamental 

parameters and expected performance criteria of the 

project so that the bidding teams can work toward a 

common solution. In some cases, this solution is 

intentionally left somewhat open to encourage innovation 

on the part of the DB team. The solution is left open, but 

the owners expected performance criteria is clearly 

defined. 

An example of this can be illustrated by the following: In a 

Design-Build contract and RFP would ask for a bridge, 

designed to handle a specified traffic load in year X, as 

opposed to an owner prescribing a certain number of 

lanes, with a certain type of bridge. This statement of 

performance versus prescription gives a Design-Builder 

flexibility to design and build many alternatives, and to find 

an owner the best solution.

On simple projects that do not involve right of way 

acquisition or environmental permits, a project can be 

awarded with less up-front design, as the consultant will be 

performing a large portion of the design work in parallel 

with construction activities. An example of this may be the 

replacement of a bridge damaged by an over-height truck 

impact. In this case, the parameters of the final product 

are well defined.

Figure 2.5.1.1-1 depicts a flowchart of a sample DB 

project. The major team members are shown in different 

colored boxes.

Advantages to the DB process are as follows:

• Accelerated Project Delivery - most agencies report 

consistently expedited project schedules. 

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Federal Highway Administration Accelerated Bridge Construction Manual 

• The design can be tailored to the contractor’s 

expertise and equipment. 

• The team can take advantage of innovative 

construction processes. 

• DB Teams are sometimes encouraged to modify the 

preliminary designs to save money. 

• Owners can obligate monies very quickly and with 

good results on meaningful capacity projects.

Disadvantages to the DB process are as follows:

• The owner needs to clearly identify and 

communicate the desired project outcomes.

• The DB team needs to complete a relatively detailed 

design process in order to bid the project. In some 

agencies, stipends are used to defer the cost of this 

process to the short-listed teams. 

• The owner does not have complete control over the 

final design. The design team is working under the 

direction of the contractor, not the agency. 

Requests for changes to the design after the bid 

often result in extra costs.

• Risk is increased on the designer and contractor. 

However, DB allows the designer and contractor to 

develop solutions to minimize risk.

• Most agencies have seen little or no change in 

project cost. Some agencies have reported higher 

costs. In these cases owners generally agree that 

the decrease in traffic disruption has positive cost 

benefit. The increase costs have been more than 

made up in a modeling of road user costs.

Even with the listed disadvantages, the ability to deliver a 

project in a short time period has compelled agencies to use 

this method for many projects. Some states have statutory 

restrictions to this form of contracting. In some cases, 

special legislation has been used to allow the use of DB on a 

limited basis. 

More information on the Design-Build process can be found 

at the FHWA website: 

www.fhwa.dot.gov/construction/cqit/desbuild.cfm. 

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Federal Highway Administration Accelerated Bridge Construction Manual 

Legend

Project Initiation

Preliminary Design

Permitting & ROW

Advertise for Proposals 

and Bids

Contractors Design Engineers

Establish Teams

Develop Design

Develop Proposal and Bid 

Price

Receive Proposals and 

Bids

Interview Teams

Open Bids

Determine Best Value

Agency

Contractor

Designer Engineer

Selection and Award

Finish Design

Build Project

Contractor/Designer Team

Figure 2.5.1.1-1 Sample Design-Build Process

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Federal Highway Administration Accelerated Bridge Construction Manual 

2.5.1.2. Construction Manager General Contractor (CMGC) 

This method of project delivery is similar to DB in that the 

designer and contractor work together to complete a 

design; however there are some significant differences. 

The fundamental difference is in the contracts with the 

owner. In CMGC, both the designer and the contractor 

have contracts with the owner, and the owner is part of the 

design team. In CMGC the owner does not relinquish

control or risk as in DB. Other attributes of CMGC include: 

• A preliminary design does not need to be completed 

prior to selection of the designer or the contractor.

• The design engineer is selected by the agency using a 

standard qualifications based approach. The design 

engineer works under the direction of the agency, not 

the contractor. 

• The contractor is selected by the agency using a 

qualifications approach.

• The selected firms (contractor and designer) form a 

design team along with the agency in a collaborative 

manner.

• The team (owner, contractor, designer) develops the 

design.

• Risks are identified and managed. Solutions to 

potential problems are resolved during the design 

phase.

Figure 2.5.1.2-1 depicts a flowchart of a sample CMGC

project. The major team members are shown in different 

colored boxes.

Advantages to the CMGC process are as follows:

• Accelerated Project Delivery - most agencies report 

consistently expedited project schedules

• The design engineer and the contractor do not need to 

perform significant up-front design work prior to the 

bid. Stipends are not necessary.

• The design can be tailored to the contractor’s 

expertise and equipment. 

• The team can take advantage of innovative 

construction processes. 

• The agency has complete control over the design. 

The design engineer is working under the direction of 

the agency.

• Contractor risk is identified during the design process 

and managed.

• Total construction costs (bid price plus change orders) 

can be lower than other contracting processes. This 

is primarily due to reduced construction change orders 

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Federal Highway Administration Accelerated Bridge Construction Manual 

and lower risk, as a result of having the contractor 

involved in the design process.

Disadvantages to the CMGC process are as follows:

• The agency needs to establish ways to select 

contractors without a design. This can be done with a 

qualifications based selection process or with a best 

value selection process, which includes a price 

component. Some states have required that 

contractors supply guaranteed unit prices for major 

items during the selection process. This is done to 

bring in an element of cost into the selection process.

• There is concern that the agency may not be getting 

the lowest price, since only one contractor is involved 

in the bid, therefore the owner should develop a 

method of verifying bid costs. 

CMGC is particularly suited for ABC projects. By having 

control over the entire design process, the owner can 

stipulate the construction methods that will best suit the 

traveling public. Innovative designs can be developed by 

the team. Risks associated with these designs can be 

identified and worked out prior to construction. In some 

cases, the owner may be willing to accept the potential for 

cost overruns if a design does not work as planned. For 

instance, if the team identifies a risk that a certain piece of 

equipment could breakdown during a short duration work 

period, the team can assess whether or not they should 

pay extra to have back-up equipment available or to 

accept the risk that this may happen and lead to a delay in

the project. If the latter option is chosen, the cost for the 

work will be decreased. Risk management is a process of 

identifying the risk, planning for it, and establishing a 

course of action to mitigate it.

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Legend

Project Initiation

Is Contractor Cost 

Acceptable? 

Solicit Qualifications from 

Design Firms

Contractors

Establish Design Team

Negotiate Design Fee

Interview & Select

Design Engineer

Agency

Contractor

Agency/Contractor/Designer Team

Develop Semi-Final 

Design

Design Engineers

Solicit Qualifications from 

Contractors

Receive Qualifications Receive Qualifications

Interview & Select

Contractor

Negotiate Design Fee

Design Engineer

Agency Estimates 

Construction

Design Engineer Estimates 

Construction Cost

Contractor Estimates 

Construction Cost

Identify and Manage Risk

Independent Cost Review 

Committee

Yes

No Can the cost be 

negotiated? 

Award Construction 

Contract

Complete Design and 

Build

Yes

Solicit Bids for 

Construction

No

Figure 2.5.1.2-1 Sample CMGC Process 

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The Utah DOT has used the CMGC process for many of 

their ABC projects with excellent results. Many feel that 

the advantages of CMGC far outweigh the disadvantages. 

The agency can exercise total control over the design 

process and has the ability to select the best designer and 

contractor. In UDOT’s experiences, the cost of projects 

was lower than DBB and DB. One of the reasons for this 

is that there are very few construction change orders. 

There is little or no possibility for misunderstandings with 

regard to details and specifications because all parties are 

involved in the development. 

More information on the Construction Manager General 

Contractor process can be found at the FHWA website 

www.fhwa.dot.gov/construction/cqit/cm.cfm. Other DOTs 

also have information on the CMGC process on their 

websites including Oregon, Arizona Utah, and Nevada.

2.5.2. Contracting Provisions

Regardless of the contracting process chosen, there are several 

contracting provisions that are commonly used on ABC projects. 

The application of these provisions varies greatly from agency to 

agency. The following sections describe the basic premise of 

each provision. 

2.5.2.1. Best Value Selection

The interstate highway system was built using the low-bid 

selection system for contractors. This system served the 

nation well; however, ABC projects often require 

contractors with special expertise. In these cases, low-bid 

contracting may lead to problems during construction if an 

inexperienced contractor is involved. Perhaps in the 

future, when ABC is more commonplace, agencies can 

return to a low-bid format. In the meantime, agencies are 

moving toward a new selection process called “Best Value” 

selection.

Best Value selection is the process where owners select 

the Design-Build team, or in CMGC where they select the 

designer and contractor. The process uses a technical 

evaluation of the contractor submitted proposal, and a bid 

or quote which are then combined to determine “best 

value”. One definition of value is “to rate something 

according to its perceived worth, quality, or usefulness”. 

Best value by definition includes a determination by the 

owner of quality of proposal at some cost.

Part of the reason for this approach is the new contracting 

methods described in the previous sections. In the 

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Design-Build contracting method, the selection process 

involves both the contractor and design engineer. 

Traditionally, in Design-Bid-Build, the selection of the

design engineer is qualifications based followed by a 

negotiated fee process. The intent is to select a high 

quality designer for the project, when public monies are 

used. In some states, there are statutory requirements for 

this approach. In most states by contrast, construction 

projects are awarded based on low bid. By including the 

design team in the selection process, a different approach 

is warranted because the agency is looking for a quality 

design combined with a fair price.

The goal of best value selection is to meld the 

qualifications based approach to the low-bid approach. 

Typically, agencies will require that Design-Build teams 

submit both a proposal package and a separate bid 

package. Other agencies use a two tiered selection 

process. First they short-list teams based on 

qualifications, and then they ask those teams to submit 

detailed bids. The final selection can then be made by 

combining the qualifications of each team with the cost 

proposal.

The simplest way to combine technical score with price is 

to assign points to technical score and points to price 

(price points are assigned inversely proportional to bid 

amount). This method is sometimes called the weighted 

criteria method. The owner can then weight the technical 

score and the price score according to the importance that 

the owner places on the criteria. In this system the high 

point total wins. Owners should carefully evaluate the 

relative weighting of the technical score and the price 

score in order to ensure that the goals of the selection are 

met.

The range of the technical score assigned to the various 

teams should also be evaluated. If the spread between 

the high and low technical score is small, the bid will go to 

the low bidder in most cases. This will encourage teams to 

place less emphasis on quality of design and innovation. If 

the technical score spread is greater, then more emphasis 

will be placed on delivering a high quality and innovative 

design. The key to this evaluation is to strike a balance 

between innovation and cost. 

According to Design-Build institute of America (DBIA), 

there are many methods for evaluation, but the primary 

ones used are the previously mentioned Weighted Criteria, 

a method called Fixed Price Competitive Design, and a 

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method called Integrated Assessment and Trade-off( 

federal model). 

Each of these methods is characterized by a process by 

which the proposals are evaluated. DBIA suggests that a 

best practice is to have that process be known to 

proposers. To quote from DBIA “ Disclosure (of the 

process) encourages participation in the owners 

competition, imparts a sense of high integrity and clarity in 

the process, and results in proposals which respond more 

closely to the owners requirements and expectations.

If an agency is interested in a best value selection process, 

they should investigate various processes in other states to 

find one that fits the goals of the agency.

2.5.2.2. A+B and A+B+C Bidding

The nature of Accelerated Bridge Construction projects is 

that a reduction in project time is desirable. The selection 

of the low bid can take into account the time component of 

the project. There are two common methods of addressing 

this in the bidding phase of the project. 

A+B bidding is a method that assigns a value to the base 

bid price (the “A” component) and a value to a time 

component (The “B” component). The low bid is 

determined the sum of these two components.

• The "A" component is the dollar bid for the contract 

work items. 

• The "B" component is the time to complete the project 

or a portion of the project converted to dollars, usually 

by using road user cost models that compute the “cost” 

of road user delays.

A+B+C bidding is similar to A+B bidding except a third 

component is added to the equation. The “C” component 

is normally used for specific milestone timeframes. For 

example, a contract may have a “B” component that is tied 

to final project completion, and a “C” component that is tied 

to the completion of a phase of construction. 

The “B” and “C” components are multiplied by a dollar 

value that is normally tied to road user costs. The contract 

is awarded based on the total of the "A", "B", and “C” (if 

applicable) components. The contract amount after award 

is limited to the "A" portion of the bid. The summation of 

the “A”, “B”, and “C” components is used to identify the 

best value.

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The dollar values assigned to the “B” and “C” components 

are open to interpretation and variation. Road user costs 

are somewhat subjective, difficult to calculate, and 

sometimes hard to justify. Agencies need to identify these 

costs and make rational decisions based on the needs of 

the project and the impacts to the traveling public.

More information on A+B+C Bidding can be found at 

various agency websites. A simple web search on “A+B 

Bidding” will uncover numerous state agency practices for 

this subject. Some states will refer to this type of bidding 

as “price plus time”.

2.5.2.3. Continuity of the Construction Process

One of the most frustrating issues for the traveling public is 

to have a construction process start and then stop for an 

extended period of time. On some occasions, this is 

inevitable such as the need to fulfill the requirements of an 

environmental permit. An example might be a limitation on 

in-river work during spawning season. 

In many cases, contractors choose to make the most 

efficient use of their staff and equipment. Shifting work 

crews from one project to another is common. It is not 

always possible to have the work flow match the available 

manpower and equipment. 

Contracts can have provisions that limit the amount of 

down time in a construction process. It is difficult to define 

what an inactive worksite is; however some provisions can 

be incorporated into the contract. An example may be that 

the girders be placed within a certain number of days after 

final acceptance of the substructures.

This approach can reduce the overall project time by 

eliminating the down time periods. It is important to note 

that this approach may increase the overall cost of the 

project. Contractors may need to hire temporary workers 

or rent additional equipment to achieve these 

requirements.

2.5.2.4. Incentive/Disincentive (I/D) Clauses

I/D clauses are contract provisions that are used to 

financially compensate or penalize the contractor for time 

spent on the construction of a project (or a portion of the 

project). Normally I/D clauses are linked to calendar days; 

however they can be linked to weekdays only. On ABC 

projects, I/D clauses have even been linked to minutes. 

For example, I/D payments may be applied to the time that 

a roadway is re-opened after weekend construction. 

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Disincentives are typically assessed when a work process 

exceeds a contract stipulated timeframe. Incentives are 

typically awarded when work is completed ahead of 

schedule. The intent of I/D clauses is not to just punish 

poor performance. The goal is also to reward accelerated 

work and minimize the loss of value of the facility through 

impacts to the traveling public. If the goal is to accelerate 

the work to something less than conventional construction, 

then the contract should include an incentive. Generally, 

the incentive rate and the disincentive rates are equal. If 

different two rates are used, the incentive rate should be 

the smaller value. 

Another option is to bid a project with a very short 

construction timeframe, and not include an incentive 

clause. This is due to fact that there may be no room for 

significant time savings. A disincentive clause would be 

justified in order to reduce the risk of a loss of service on 

the facility. The bids for the work will generally be higher in 

this scenario as contractors include the costs of extra 

workers and extra work shifts into the contract. This 

avoids the need for the agency to carry incentive funds in 

the contract for the duration of the project. The contractor 

also does not need to wait until the end of the contract to 

capture the extra costs for the increased effort. 

I/D should not be confused with Liquidated Damages. 

Liquidated Damages are normally linked to the agency 

costs associated with the delay of a project. 

The dollar amounts of I/D clauses are normally based upon 

road user costs and inconvenience to the traveling public. 

Impacts to traffic safety, and traffic maintenance can also 

be weighed in this process. In many cases, this approach 

will generate excessive incentive values, which may not be 

justified on a cost/benefit basis. Another approach that 

can be used is to calculate the contractor’s premium on 

labor due to increased work hours. A cap of 5% of the 

total contract amount is recommended as a maximum 

incentive value.

The use I/D clauses will inevitably bring about a need for

careful time tracking. All parties need to be cognizant of 

the time spent on a project. Delays in agency approval of 

submittals may be grounds for time extensions, which will 

greatly affect the I/D values.

More information on I/D clauses can be found at various 

agency websites. A simple web search on “incentive 

disincentive clauses” will uncover numerous state agency 

practices for this subject. The FHWA also has technical 

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advisory on this subject entitled “Incentive/Disincentive 

(I/D) for Early Completion” (T5080.10). It can be found at:

www.fhwa.dot.gov/construction/contracts/t508010.cfm. 

2.5.2.5. Warranties

Warranties are common in the retail marketplace. Virtually 

every major purchase in the Unites States comes with 

some sort of warrantee. The purpose of a warrantee on a 

purchased item is to provide a level of comfort to the 

purchaser with regard to the quality of the product and to 

provide recourse is the product fails. 

The construction of bridges is a different matter. The 

quality of bridges has always been dictated by the quality 

control procedures that are undertaken during design and 

construction. Designers follow typical procedures such as 

checking of calculations and independent checking of 

entire designs. Construction inspectors in the field and in 

fabrication shops ensure that the plans and specifications 

are followed precisely. 

Until 1995 the use of warranties was not permitted on 

Federal-aid projects. This was based on the concern that 

participation in a warranty payment would constitute an 

indirect Federal-aid participation in maintenance costs. 

The advent of innovative contracts such as Design-Build 

brought about new interest in warranties. In DB contracts, 

the agency has less control over the design and potentially 

the construction. The Design-Build team has much more 

control over the quality control procedures. For this 

reason, new interest in warranties arose. In 1995, FHWA 

began allowing the use of warranties (Title 23 C.F.R. 

635.413 – Guaranty and Warranty Clauses).

Warranties are typically used for specific project items and 

not the entire project. Routine maintenance items such as 

replacement of damaged beam rail do not qualify for 

warranties. Some common warranty items include asphalt 

concrete pavements, bridge painting, traffic striping, bridge 

bearings, and bridge expansion joints. These items 

heavily depend on material performance, which justifies 

the use of the warrantee.

The length of time for typical warrantees is between 1 and 

5 years. Some agencies use warranty bonds in contracts 

to assure that a warranted item survives the warranty 

period in the prescribed condition. The warranty bond can 

be repaid at the end of the warranty or incrementally over 

the life of the bond.

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ABC will inevitably lead to use of more innovative products 

and materials. Performance warranties can be used to 

alleviate the agency concerns over the use of new 

techniques and products. 

FHWA has specific rules governing the use of warranties. 

Agencies should coordinate with FHWA on the use of 

warranties on specific projects. 

2.5.2.6. Lane Rental

One of the goals of ABC is to minimize impacts to the 

traveling public. Lane closures can cause major disruption 

to the transportation network; however they are inevitable 

on many projects. Closure of lanes also has a negative 

impact on the public perception of construction projects. 

Lane closures with seemingly idle construction work can 

infuriate passing vehicles, especially if the closure has 

resulted in a travel delay.

Lane Rental is a means of reducing the impacts to road 

users by minimizing the amount of delays caused by 

construction. The contractor is charged for the amount of 

time that a lane is out of service. The amount of the 

charge may vary by time and day of the week. In previous 

sections of this manual, the concepts of roadway user 

costs were discussed. On most projects, roadway user 

costs are nebulous costs that are borne by society; 

however they cannot be applied to the actual construction 

of the project. The Lane Rental concept is a way of 

applying roadway user costs to the value of the project, 

since the monetary value of the lane closure is based in 

part on the roadway user cost impacts. 

Lane Rental requires that contractors account for roadway 

user impacts during construction and in the bid process. 

The bid typically consist of a base bid for the actual 

construction and a secondary bid for the lane rentals, The 

two values are combined in the bid analysis resulting in a 

best value selection process.

More information on Lane Rentals can be obtained from 

several state departments of transportation (such as 

Minnesota and Washington) that have lane rental policies 

and specifications in place. 

2.6. Applicability of ABC Technologies to Different Bridge Projects

ABC is most effective for projects that require the management of traffic 

during construction. This section will cover how ABC can be applied to 

the various types of bridge projects that typical transportation agencies 

manage. Chapter 3 will explore how to incorporate ABC into the 

planning of these various bridge projects.

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2.6.1. Rehabilitation of Existing Bridges

The national bridge inventory is aging; therefore, many of the 

bridges in the United States have significant deterioration. Most of 

this deterioration is centered on the bridge superstructure. 

Concrete deck replacement projects are becoming more common. 

Deterioration is not limited to the decks. The supporting girders 

also experience deterioration due to leaking bridge joints and lack 

of maintenance.

On many of these bridges, the substructure is in better condition 

when compared to the superstructure. This is especially true for 

single span bridges and continuous span bridge without deck 

joints. On many projects, rehabilitation of the substructure 

combined with replacement of superstructure elements is feasible. 

The following sections discuss how ABC can be used for the 

execution of bridge rehabilitation projects.

2.6.1.1. Deck Replacement

Replacement of bridge decks is one of the most common 

uses of ABC. The installation of a bridge deck is time 

consuming, requiring significant manpower to form the 

deck, place reinforcing, cast concrete, cure the concrete, 

and strip the forms. This labor intensive work is difficult 

under the best circumstances, but in a situation where 

traffic management is required, it becomes even more 

complicated. 

Three basic forms of ABC deck replacement strategies 

have been used in the United States. The first is stay-inplace deck forms. These forms consist of corrugated 

metal panels that are designed to support the reinforcing 

steel and the wet concrete of the deck. The benefit to this 

method of deck construction is that it eliminates the need 

to strip the forms after the concrete is cured. The 

disadvantage to this system is that it still requires the 

placement of reinforcing steel, casting of concrete and 

curing of concrete, which does not result in a significant 

time savings during construction. Also, future visual 

inspection of the underside of the deck is not possible.

The second ABC deck replacement strategy is the use of 

precast and prestressed concrete partial depth deck 

panels. These panels are typically cast to half the 

thickness of the finished deck. The remainder of the deck 

is made up of one layer of steel reinforcement and site cast 

concrete. The panels are designed to span from girder to 

girder with reinforcement designed to accommodate the 

positive deck bending moments. Negative deck bending 

moments are accommodated by the top layer of field 

placed reinforcement. The benefits and disadvantages of 

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this system are similar to stay-in-place deck forms except 

that the panel is a structural part of the deck , and is 

exposed for future visual inspections.

The fastest form of deck placement is through the use of 

full depth prefabricated deck panels. Different systems 

have been used in the United States including open grid 

steel (often partially filled with concrete), exodermic deck 

panels (grid panels with a composite concrete topping), 

fiber reinforced polymer panels, aluminum extrusion 

panels, and precast concrete panels. 

The precast panels make up the majority of the ABC 

projects. There is been significant research into the use of 

precast concrete deck panels. The research includes the 

composite connections between the panel and the girders 

and the connections between the panels. In fact, it is 

reasonable to state that precast concrete deck panels are 

one of the most thoroughly researched ABC bridge 

technologies. 

The AASHTO LRFD Bridge Specifications [8] includes 

provisions for precast concrete deck panels. The basic 

provisions include:

 Transverse connections using a grouted shear key

 The use of post-tensioning to join panels in areas 

where the deck is exposed to road salts. The level 

of effective post-tensioning is specified at 0.25 ksi 

minimum.

 The composite connection between the panel and 

the girder can be made via shear connectors 

placed in block outs that are filled with grout.

Figure 2.6.1.1-1 shows a deck replacement project 

involving the use of full depth precast deck panel project 

during construction. The longitudinal post-tensioning ducts 

can be seen at the edge of the panel.

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Figure 2.6.1.1-1 Full Depth Precast Concrete Deck Panels

(source: New Hampshire DOT) 

The performance of these provisions has been verified by 

a number of state agencies. The Connecticut DOT has 

had several decks in service for almost twenty years with 

no leakage of the deck joints and excellent performance. 

Figure 2.6.1.1-2 shows the underside of one of the 

Connecticut Bridges after 20 years in service. 

Figure 2.6.1.1-2 Underside of Full Depth Precast Deck Panels

(after 20 years in service)

Research has been completed on deck panels that are 

connected without post-tensioning. This work was 

completed under NCHRP Project 12-65 (Report 584) [9]. 

The research focused on the following concepts:

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 Develop a girder connection with a blind pocket (not 

protruding through the top of the deck). The idea was 

to minimize the amount of filled deck voids to promote 

the use of precast decks without overlays.

 Develop a panel to panel connection that did not 

require post-tensioning.

 Investigate the use of larger maximum shear 

connector spacing (up to 4 feet on center).

These concepts were developed and successfully tested. 

Both the blind pockets and the panel connections use 

standard structural steel tubing to produce confined 

spaces to develop the forces required to make the 

connections. The shear connector pockets are filled with 

non-shrink grout through small ports and the panel to 

panel connection is made with a grouted slot cast into the 

edges of the panels. Figure 2.6.1.1-3 shows the details of 

this system, and Figure 2.6.1.1-4 shows the construction 

of one of the first bridge decks using this system. The 

project was built by the Texas DOT.

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Figure 2.6.1.1-3 Blind Pocket and Bar Slot Connection Details

(source: NCHRP Report 584 [9]) 

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Figure 2.6.1.1-4 Precast Deck Panel Project in Texas

Based on NCHRP Report 584 Details

(source: Texas DOT) 

Several agencies have developed standard details for 

precast full depth concrete deck panels. There are several 

sources of details, manuals and specifications. The Utah 

DOT has developed standard details that include blind 

pockets and longitudinal post-tensioning. They have also 

developed manuals and specifications for full depth deck 

panels. They can be found at www.udot.utah.gov (search 

“ABC”). 

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The Precast/Prestressed Concrete Institute has a 

Northeast Bridge Technical Committee that has developed 

typical details and a manual for full depth precast concrete 

deck panels. This information can be found at 

www.pcine.org. 

2.6.1.2. Superstructure Replacement

The use of ABC for superstructure replacement projects is 

common. ABC techniques are particularly well suited for 

superstructure replacement projects, since the time 

consuming process of building foundations and 

substructures is not required. Several states have used 

several different ABC techniques to accomplish this type of 

work in very short order. 

Several states have used SPMT technology or lateral 

skidding/sliding technology to remove and install entire 

bridge superstructure systems. The new superstructures 

can be built off site and moved into position in as little as a 

few hours. Figure 2.6.1.2-1 shows an SPMT 

superstructure replacement project on Interstate 80 near 

Salt Lake City. This project involved the replacement of 

four superstructure spans. The spans were replaced in 24 

hour time periods on two separate weekends (2 spans per 

weekend). The installation was complete in a matter of 

hours. The remainder of time was spent completing the 

approach slab and barrier installation.

Figure 2.6.1.2-1 Superstructure Installation Using SPMTs

Another ABC method that is well suited for superstructure 

replacement projects is the use of modular bridge 

elements. Several states have constructed new 

superstructures using prefabricated beam/deck modules. 

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Sections 2.4.3, 2.4.4, and 2.4.5 discuss the methods for 

this type of installation.

The third method of ABC that is available is the use of 

prefabricated bridge elements. The construction can 

include new beams, combined with a prefabricated deck 

system. The New Hampshire DOT completed a single 

span superstructure replacement in 2010 using steel 

beams and precast concrete full depth deck panels. The 

bridge carries Interstate 93 over a local road in Concord, 

New Hampshire. The superstructure was replaced in one 

weekend using this method. Figure 2.6.1.2-2 shows the 

completed bridge.

Figure 2.6.1.2-2 Completed Superstructure Replacement

Constructed with Prefabricated Elements 

2.6.1.3. Substructure Replacement

On some bridges, the substructure may also be in 

disrepair. This can be caused by leaking deck joints and 

spray from vehicles passing underneath. If abutments are

deteriorated, full bridge replacement or patching of the 

abutment may be in order. This is due to the difficulty of 

replacing an abutment without significant disruption to 

adjacent areas. 

Accelerated replacement of pier columns and caps has 

more potential. It is possible to remove old pier columns 

and caps and replace them with prefabricated pier 

elements if the footings and foundations are in sound 

condition and structurally adequate. Closure pours at the 

base of the columns can be used to connect the old 

footings to the new pier elements. If an existing pier is 

supported on a spread footing, it is possible to build the 

new pier alongside the existing bridge on rails and jack it 

into place in a similar fashion to lateral superstructure 

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skidding/sliding. Once in place, the footing can be 

underpinned with grout to seat it on the subgrade.

2.6.2. Replacement of Existing Bridges and New Bridges

Replacements of entire bridges and the construction of new 

bridges differs from deck replacement and superstructure 

replacement projects in that there is also a need to replace the 

substructures and foundations. This adds a level of complexity to 

the project; however, ABC methods are still appropriate in many 

cases. 

Replacement of an existing bridge is different than construction of 

a new bridge on a new alignment. Often, traffic needs to be 

accommodated during construction. This either requires building 

the bridge in and around the traffic, or building the bridge with a 

traffic detour. ABC can be used to minimize impacts to traffic in 

both of these scenarios. The following sections describe the role 

that ABC can play in several different replacement strategies.

2.6.2.1. Staging

On many projects, traffic needs to be maintained through 

the construction site if a suitable traffic detour is not 

available. This often involves multiple stages of 

construction. ABC can be used to minimize the duration of 

each construction stage. All forms of ABC described in 

Section 2.3 and 2.4 can be used for stage construction 

projects. In some cases, complete superstructure 

prefabrication may not be possible due to conflicts with the 

adjacent roadways; however the use of prefabricated 

elements is always possible in stage construction projects. 

Individual prefabricated elements can be used for all 

portions of the substructures and superstructures.

On any project where staging is being considered, the 

project team should investigate the potential for changing 

from staged construction to ABC with full closure with a 

detour. This approach will offer the greatest opportunity for 

accelerating the construction since the contractor will have 

full access to the site for manpower and equipment. It also 

offers the safest work zone for workers and inspectors. 

Businesses have also expressed approval of a short 

duration mobility impact versus a long duration stage 

construction project with the coinciding mobility impacts. 

During one of the FHWA Accelerated Construction 

Technology Workshops, the technology team determined 

that the construction time for a staged replacement project 

could be reduced from two years to three months by using 

a full closure with a minor detour. This approach should be 

investigated for all projects that are scheduled for multistage construction.

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2.6.2.2. Full Closure and New Construction

On many projects, the entire construction site can be made 

available to a contractor for the construction of an entire 

bridge. This occurs on new bridges being built on new 

roadway alignments (sometimes referred to as 

“greenfields”), and on bridges that are built with traffic 

detours.

The previous section outlined the benefits of ABC on 

projects with detours. Full closure of the bridge offers 

significant benefits to the ABC process. The use of ABC 

on projects that involve detours is appropriate if the detour 

is long or has undesirable geometrics. ABC can be used 

to minimize the length of time that the detour is in place. 

One might think that ABC is not appropriate for greenfield 

construction. In many situations, this may be the case. 

Often, greenfield construction involves the construction of 

significant portions of roadway along with the bridges. 

Sometimes, the construction of the bridge is not on the 

critical path for the overall construction of the projects; 

therefore, ABC may not be necessary. 

There may be certain situations where ABC may still be 

applicable in a greenfield construction site. Significant 

construction limitations may be imposed by regulatory 

agencies for bridges that are spanning over 

environmentally sensitive habitats. ABC can be used to 

minimize the amount of time that the construction impacts 

the habitat. If the bridge is a new structure over an existing 

roadway, the impacts to the lower roadway may still 

warrant an ABC approach in order to minimize the impacts 

to the vehicles below.

All forms of ABC strategies are applicable to complete 

bridge construction either under a roadway closure 

scenario or for new greenfield construction. 

2.6.3. Effect of Structure Type on ABC Methods

Virtually any bridge can be built using ABC methods; however 

certain bridge features can have an effect on the ABC process. 

This section covers some of the most common features of bridges 

that affect the ABC process.

2.6.3.1. Curved, Skewed and Flared Bridges

Most bridges built in the early 20th century were 

constructed without horizontal curvature or skew. Often, 

engineers sacrificed roadway geometry for the simplicity of 

design and construction of square and straight bridges. 

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During the development of the interstate highway system 

in the latter half of the 20th century, a need arose for more 

complex bridge geometries that could match the 

complexities of the high speed roadway designs, and 

reduce impacts to right-of-way, utilities and 

environmentally sensitive areas. In addition, problems with 

river scour led to substructure elements that were 

designed to minimize turbulence in flowing waters. Today, 

curved and skewed bridge alignments are commonplace. 

The definition of skew varies in different states. The 

terminology used in this manual is based on the definition 

that most states use, which is defined as the angle 

measured between the centerline of the bridge elements 

(abutments, piers, joints, etc.) and a line perpendicular to 

the roadway alignment. (i.e. a bridge with zero skew is 

square bridge).

The curve and skew of a bridge does have an impact on 

the use of ABC; however it does not preclude the use of 

the methods described in this manual. Often, these factors 

simply affect the detailing and complexity of the processes.

The following are some of the issues for various ABC 

methods with regard to bridge skew:

 Skews greater than 25 degrees are required to 

have the main transverse reinforcement in the deck 

placed perpendicular to the girders (AASHTO 

LRFD Bridge Specifications [8]. This results in 

deck panels that are also square to the bridge 

girders. This will require the use of non-rectangular 

panels at the ends of the bridge, or large closure 

pours.

 Large skews can have an impact on the complexity 

of the lifting and moving of a bridge superstructure 

using SPMTs. or lateral slide-in technologies.

 The complexity of prefabricated substructure 

elements and connections increases with skewed 

designs.

The following are some of the issues for various ABC 

methods with regard to bridge curvature:

 Curvature requires that precast full depth deck 

panels be made trapezoidal to accommodate deck 

curvature. 

 Longitudinal post-tensioning in precast full depth 

deck panels needs to be designed to account for 

the loss in post-tensioning force due to friction in 

the ducts if the ducts are run along the curvature of 

the roadway.

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 Curvature can have an impact on the complexity of 

the lifting and moving of a bridge superstructure 

using SPMTs. or lateral slide-in technologies. For 

difficult geometries, the superstructure may need to 

be moved into place above the adjacent roadway 

and jacked vertically down to the bridge seats after 

they are positioned in the horizontal position. This 

is especially true for curved bridges with nonparallel substructures.

All of these issues can be overcome with sound 

engineering judgment and careful planning. Attention to 

detailing and geometry are critical to the success of any 

curved or skewed bridge design regardless of whether or 

not ABC methods are employed.

2.6.3.2. Bridges with Transverse Floor Beams (trusses and widely 

spaced girder bridges)

Most bridges built in the United States are designed and 

constructed with multiple beams and girders that are run 

parallel to the roadway alignment. This method of 

construction, sometimes referred to as multiple stringer 

bridges, offers several advantages to other bridge types. 

Stringer bridges are often very redundant and have the 

ability to sustain significant damage without collapse. 

There have been many documented cases where girders 

have fractured due to fatigue, truck impacts, and ship 

impacts, without collapse of the bridge superstructure. 

Stringer bridges are also ideal for situation where future 

widening of the roadway is anticipated. The popularity of 

this bridge type is the reason why the majority of the 

discussion and details in this manual are based on parallel 

stringer bridges.

There are other instances where other framing techniques 

are appropriate. These primarily occur in long span 

bridges and older bridges that were constructed with 

widely spaced longitudinal main members (trusses, large 

girders, suspension bridges). These bridges typically have 

transverse floorbeams spaced at regular intervals that 

span from the main load carrying members.

Many of the ABC techniques described in this manual are 

also applicable to these bridge framing systems. In fact, 

some of the techniques are particularly well suited for 

these bridges. The repetitive nature of floorbeam system 

structures leads to economies of scale. It is not unusual 

for a bridge to have several hundred floorbeam bays with 

intermediate framing that is essentially the same in every 

bay.

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The gantry crane systems described in Section 2.4.4 have 

been used to replace portions of bridge deck/stringer 

modules using overnight construction closures. The 

spacing between floorbeams is normally small enough to 

make the handling of the modular elements reasonable.

2.6.3.3. Box Culverts 

Some states construct culverts using CIP reinforced 

concrete construction. This type of construction is very 

slow due to water handling needs and the difficulties of 

forming the roofs of the culverts.

Construction of culverts is sometimes seen as ancillary 

part of roadway construction. This is normally true for new 

construction; however if there is a need to replace a culvert 

on an existing highway facility, the construction can be 

critical to the function of the highway. Deterioration of 

culverts has become a problem in the last 20 years. 

Deterioration of culvert inverts due to corrosion and stream 

bed abrasion has brought about a need for more 

replacements. 

Precast four sided and three sided culverts are becoming 

more popular. They offer the potential to construct a 

culvert quickly during periods of low flow. The bottomless 

three sided culverts are seeing more widespread use. 

These structures allow for construction of the abutment 

footings without a temporary relocation of the channel with 

greatly reduced impact on the environment. 

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Chapter 3 PBES for ABC – Planning and Scoping Projects

In the last decade, there have been many ABC projects in the United States using the 

various techniques described in Chapter 2. These techniques and projects are helpful 

for generating ideas; however, it can be difficult for project planners to decide how to 

make a certain technique fit into particular projects. 

There are two major steps in the project planning and scoping process that apply to 

ABC. First, the agency needs to determine if ABC is appropriate at a site. This decision 

making process needs to include a study of several factors including but not limited to 

ADT, potential detours, emergency routes, road user costs (Section 3.1 will describe 

ways to use these factors in a decision making process). The second step involves a 

decision as to what ABC technology is appropriate for a site once a decision has been 

made to use an ABC technology. This step can be challenging since multiple ABC 

technologies may be appropriate at a site. This chapter will explore ways to evaluate 

sites and make sound decisions as to the ABC technology that is appropriate for each 

site.

The FHWA has completed a series of summit meetings for the “Every Day Counts” 

(EDC) initiative. These summits were used to encourage state and county agencies to 

make use of new technologies including PBES. All 50 states, Puerto Rico, the District of 

Columbia, and several territories were invited to these summit meetings to learn about 

EDC, provide comments and input, and start the process of implementing the new 

technologies. During the summit meetings, the following comments represent typical 

concerns and issues with regard to the project planning process:

• “I can’t see how ABC would work in my case”. 

• “I cannot figure out which type of ABC technology is right for my site”.

• How do I get an ABC project started?

Information about the EDC Summit meetings can be found at the FHWA EDC website at 

www.fhwa.dot.gov/everydaycounts/index.cfm. 

The AASHTO TIG and FHWA had developed a process called Accelerated Construction 

Technology Transfer (ACTT). The purpose of this process was to assist agencies with 

the implementation of ABC on specific projects. On a typical project, a workshop is held 

where a group of experts brainstorm on how to build a project faster based on the site 

constraints of the particular project. After three days, a consensus is reached on the 

most appropriate ABC method for the project. In some cases, multiple methods are 

identified. Following the workshop, the agency explores the options and developed the 

final project concept. In several ACTT workshops, it was determined that the projects 

were too far along in the development process to incorporate a particular ABC 

technology. The most successful ABC projects are ones where ABC technologies are 

integral to the project planning and scoping process from the start; therefore it is 

important to consider ABC at the earliest planning stages, and in the early phases of a 

programmatic implementation of ABC. The ACTT workshops were a successful 

program that assisted agencies in the decision making process for ABC projects. The 

following sections outline a process that is similar to the process used in the ACTT 

workshops.

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3.1. ABC Decision Making Process

Chapter 1 of this manual explored the reasons for using ABC and the 

benefits associated with ABC. One of the most important processes in 

the project planning is making the decision to use ABC on a particular 

project. The previously published FHWA Manual entitled DecisionMaking Framework for Prefabricated Bridge Elements and Systems 

(PBES), Publication Number FHWA-HIF-06-030, May 2006 [1] is an 

excellent source of information on the process of planning a successful 

ABC project. It is recommended that all projects be evaluated using a 

decision making framework during the project planning process.

Some agencies have taken the decision making framework document 

and modified the framework to account their specific practices and needs. 

They have tailored the process to meet the goals of their specific 

agencies. Utah DOT has developed a new approach that involves 

measured responses to multiple decision measures such as ADT, detour 

time, evacuation route, economy of scale, applicability to standards, 

worker safety, environmental issues, railroad impacts, and weather 

limitations. The individual measures are weighted in order to be 

consistent with the Department policies. The weighted measures are 

then used to calculate an ABC rating, which is used to provide direction 

on the use of ABC for the project. If the project scores a high rating, 

ABC is used. For projects with low ratings, ABC is not used. For projects 

with marginal ratings, the costs of the various construction options are 

studied. Any potential increase in cost due to ABC is weighed against 

road user costs. If the Department policies and direction change in the 

future, the weighting factors can be adjusted to coincide with the 

changes. The result of this new approach is that a bridge with one 

significant control factor may actually rate lower than a bridge with several 

moderate control factors. 

Oregon DOT in collaboration with 7 other states through a pooled fund 

study has developed another decision making process that will account 

for the characteristics of the project such as project size, complexity, road 

user characteristics, environmental requirements and construction site 

attributes. This tool that can assist agencies with the decision making 

process to compare conventional construction with ABC. The FHWA will 

make it available to the FHWA Division offices, State DOTs and local 

transportation agencies. 

3.2. Decision Process for Selection of Appropriate ABC Methods

Once a decision is made to explore ABC on a project, the agency needs 

to determine which types of ABC technologies are appropriate for the 

project. This determination is not always obvious to the project planner, 

especially with the various technologies in use today. The following 

sections outline a basic process that can be used to determine the 

appropriate types of ABC methods that are feasible for the project. The 

basic family of ABC component listed in Chapter 2 includes:

• Foundation and Wall Elements

• Rapid Embankment Construction

• Prefabricated Bridge Elements & Systems

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• Structural Placement Methods

• Fast Track Contracting 

Chapter 2 describes each of these components in more detail. For the 

context of this section, the decision to use several of these technologies 

is left out of the decision process for the following reasons:

• Continuous flight auger piles: This is a technology that is linked to 

a particular bridge type (deep foundation), that is not necessarily 

tied to the ABC decision process. All bridges that are required to 

be supported by deep foundations should consider this 

technology. 

• Longitudinal Launching and Pivoting: These technologies are 

relatively rare and only applicable to certain situations. The 

majority of ABC projects will not lend themselves to these 

technologies. Launching and pivoting should be considered for 

new bridges and on bridges placed on new alignments where the 

superstructure can be built behind the proposed abutment and 

moved into place.

• Fast Track Contracting: These technologies are applicable to all 

ABC projects.

In some cases, only one method of ABC will work for a project site. In 

many cases, multiple options will be feasible. In these cases, the owner 

will need to further investigate each option and weigh the major 

contributing factors in the final decision making process.

3.2.1. Defining the Problem

Before a decision can be made on the appropriate methods of 

ABC for a given project, the constraints of the project must be 

identified and studied. This can be used as a starting point for the 

ABC method selection process. 

The following sections contain common controls that define the 

project site characteristics. These characteristics will have an 

impact on the planning process and the ABC technologies that are 

appropriate for the site. 

3.2.1.1. Site Constraints

In order to determine the appropriate methods for ABC, the 

design team needs to evaluate the project site and 

surrounding area. Site constraints can have a significant 

impact on the practicality of the various ABC techniques. 

These constraints also can have a significant impact on the 

construction time and cost. 

The following sections describe the typical site constraints 

encountered on typical bridge projects. This list is not 

intended to be all-inclusive. Each site, especially sites in 

urban environments can contain unique challenges and 

must be accounted for.

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Water Crossings

Bodies of water can be a significant obstacle to ABC; 

however in some cases they can be a significant 

opportunity. One method of large scale prefabrication 

is delivery of the prefabricated bridge system via 

barges. The following constraints should be identified 

by the design team as a minimum: 

• Is the body of water is navigable and 

accessible by barge?

• Is the water tidal or subject to significant 

elevation fluctuations?

• Is the depth of water adequate to 

accommodate barges?

• Are there environmental constraints for in-water 

construction?

Some bodies of water are not accessible by 

conventional barges; however it may be possible to 

launch a segmental barge near the bridge site. These 

barges are modular and can be transported to a site in 

pieces on trailers. Once in the water, the modules can 

be joined to form a larger barge. A number of 

configurations can be used to support large loads. 

Designers should investigate the depth of water in any 

potential travel path for a barge. The depth of the 

barge should be determined after completing 

bathymetric surveys and investigating draft depths of 

typical barges.

Highway Grade Separations

Bridges that span over roadways make up a large 

portion of the population of bridge structures. 

Roadways under bridges often offer more flexibility in 

construction methods when compared to railroad 

crossings. It has been demonstrated on many 

occasions that entire bridge structures can be 

transported on normal roads using SPMT’s. The wheel 

loads of SPMT’s can be adjusted by adding axles to 

reduce the individual axle loads and the local effects of 

the tires by spreading the load out. Steel plating can 

also be used to spread wheel loads over shallow 

buried utilities. By keeping the wheel loads within 

acceptable parameters, it is possible to move a bridge 

over existing utilities, pipes and small culverts. Small 

bridges can also be crossed using temporary bridging 

plates and beam that can be installed over the roadway 

very quickly.

The design team needs to identify the following 

roadway parameters as a minimum:

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• What are the required clearances for all phases 

of construction?

• What are available lane closures above or 

below the bridge?

• Are there reasonable detours available?

• Are there available work zones at the ends of 

the bridge?

• What is the available room adjacent to the 

bridge?

As with railroad crossings, it may be possible to move 

large-scale elements using SPMT’s. Cranes located on 

the lower roadway may also facilitate the installation of 

prefabricated components. Figure 3.2.1.2-2 depicts a 

potential installation of modular superstructure elements 

using cranes located on a local road under a limited 

access highway.

Railroad Crossings

Railroads also present challenges for ABC projects. 

As with water crossings, rail crossing can also provide 

opportunities. Rail transport can accommodate larger 

and heavier elements when compared to roadway 

delivery methods. 

Railroad access if often limited and sometimes subject 

to rigid time schedules. Closure of roadway lanes can 

be accommodated with detours; however railroad 

closures often result in the shut-down of larger rail 

systems. 

The design team needs to identify the following railroad 

parameters as a minimum:

• What are the required clearances for all phases 

of construction?

• What are the weight restrictions and clearance 

limitations of the rail line approaches leading to 

the site?

• Is there a nearby siding that can be used for 

storage and offloading of elements?

• What are the available track closure periods?

• Is the line electrified (catenary above the rails or 

a third rail on the ground)?

• Is there signal equipment and/or signal lines in 

the area?

• Can temporary fill be placed between and 

around the rails for temporary equipment 

placement?

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With adequate track closures and temporary fills, it 

may be possible to move large-scale elements over 

tracks using SPMT’s. Cranes located on the tracks 

during track outages may also facilitate the installation 

of larger modular elements, since the reach of the 

cranes can be reduced. The tracks can also facilitate 

the delivery of heavy prefabricated elements to the site. 

The weight and clearance limitations on element 

delivery will control the size of the elements that can be 

shipped.

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Geotechnical Constraints

Many of the ABC methods described in this manual 

involve the use of specialized equipment. SPMTs can 

effectively distribute large loads over large areas, 

thereby reducing the unit pressure on the supporting 

soils. Cranes can produce large concentrated loads in 

small areas. A thorough review of the existing soils 

below any potential work areas needs to be 

undertaken. This can include subsurface explorations 

and laboratory testing. 

The duration of loading can have an impact on the 

capacity of the soils to resist construction loads. Long 

term settlement is not normally a significant concern on 

ABC projects due to the short duration of the applied 

load. If a crane is to be placed in one position for some 

time, the effects of settlement may need to be 

investigated, especially if there are subsurface utilities 

in the area under the crane.

Stability of the supporting soils under equipment can 

lead to disastrous outcomes. Often equipment is 

placed near the edges of the embankments near the 

bridge. The stability of the embankment (both local 

and global) should be checked to ensure that the soil 

will be stable during the use of the equipment.

If staging areas are proposed combined with an SPMT 

installation, the travel path for the SPMT should also be 

studied. In many cases, steel plating can be used to 

Figure 3.2.1.2-2 Crane Access from Local Street

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better distribute the individual wheel loads on 

questionable soils. 

3.2.1.2. Staging Areas

Many methods of prefabrication can make use of staging 

areas. Most roadways will have shipping limitations on the 

size and weight of the prefabricated elements. It may be 

desirable to allow a contractor to prefabricate elements in a 

near-site staging/fabrication yard. This will greatly reduce 

the complexity of installing the elements and allow for 

larger and heavier lifts. Staging areas can also open up 

the potential for large-scale prefabrication and installation 

with SPMT’s. The design team needs to investigate the 

following opportunities and parameters as a minimum:

• It there room within the highway right of way to 

establish a staging yard?

• Is the area large enough for fabrication of the entire 

superstructure including room for cranes?

• Are there overhead wires near the staging area and 

along the travel path from the area to the bridge? If 

so, can they be easily relocated or removed?

• Are there any sensitive underground utilities or 

structures along the travel path from the area to the 

bridge? If so, can they be bridged?

• Are there available work zones at the ends of the 

bridge?

• Is there available room adjacent to the bridge?

It is reasonable to assume that large-scale prefabrication 

combined with an SPMT bridge move is reasonable for 

most roadways. It is possible to drive SPMT’s over 

underground utility pipes and small culverts. In some 

cases, bridges can be driven over other bridges. Figure 

3.2.1.3-1 shows a bridge being moved over a previously 

placed bridge in Interstate 80. The lower bridge was 

strengthened by the addition of intermediate temporary 

supports.

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Figure 3.2.1.3-1 SPMT Bridge Move over another Bridge

(source: Utah DOT) 

Large-scale prefabrication can be combined with barge 

installations as well. It is possible to build a bridge 

superstructure on barges, but the costs of barge rental and 

the difficulties of placement of erection equipment can 

reduce the viability of this method. 

It is possible to build the superstructure on land and then 

transfer it onto barges using SPMT’s. There needs to be 

adequate draft near the water’s edge to place the barge 

close to shore. The design team should investigate the 

access to the water’s edge and the depth of water at the 

access point.

3.2.1.3. Traffic Management

Maintenance of traffic can be one of the most complex 

parts of the replacement project. The need for traffic 

management often leads to multi-stage construction 

processes with shifting traffic. In some cases, the new 

bridge is overbuilt in order to accommodate lanes during 

one of the construction stages.

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The difficulties of traffic management is a common reason 

for choosing ABC techniques in the first place; however 

accommodating the traffic can also present one of the 

most significant challenges. ABC methods can reduce 

construction time from several years to several months, or 

even several days. Detours are often not a desirable 

approach; however if the construction time can be reduced 

to a reasonable level, the opportunities for short term 

detours may be more acceptable. For these reasons, 

planners should consider short duration detours combined 

with ABC.

The following are examples of typical quantitative and 

qualitative measures should be identified for any potential 

detour:

• Length of detour and time to traverse the detour 

route

• Length of time that the detour will be in place

• Land use along the detour and impacts to adjacent 

businesses and residences

• Roadway geometry

• Traffic flow and signal timing 

• Mass Transit routes

• School bus routes

• Access for emergency vehicles

 

Detours

Detours not only have a cost impact to the project, but 

they also have an impact on both the travelers and the 

surrounding communities. Residents along a detour 

route will not find the addition of significant traffic 

desirable. Businesses adjacent to the project site will 

be concerned with loss of revenue due to decreased 

traffic. This loss of revenue is measurable; however so 

are the effects of a long-term multi-stage construction 

project. Maintenance of traffic through a project site is

a double edged sword for businesses. They would 

prefer to have steady traffic access to their 

establishments instead of a detour of traffic away from 

their site. The traffic volumes on staged construction 

projects without detours will typically decrease as 

travelers choose alternate routes to avoid the 

construction site. This leads to a long-term decrease in 

business over the entire construction process. A 

detour has a more acute impact to the amount of 

vehicles passing a particular site; however this can be 

mitigated by substantially reducing the time for the 

disruption. Many businesses have noted a preference 

to have a more severe short-term reduction in traffic 

versus a long-term moderate reduction in business. 

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All reasonable detours should be identified and 

studied. The geometry and traffic capacities of the 

detours needs to be determined to ensure that the 

peak flows can negotiate the detour without significant 

delay. The impacts to travelers should be studied 

including road user costs. The impacts to through 

traffic as well as local traffic along the route need to be 

assessed. 

On projects in rural locations, there may not be many 

detour options. The goal should be to determine the 

detours that can accommodate the anticipated traffic in 

a safe an efficient manner.

On larger complex projects in urban locations that 

involve limited access highways, multiple levels of 

detours may be in order. For instance, one detour can 

be used for traffic in the immediate vicinity of the 

project site, and a separate detours used for long 

distance through travelers on the highway. Variable 

message signs can be used to alert interstate vehicles 

and offer recommended interstate detours around the 

project sites.

The Massachusetts DOT used this approach during the 

planning for a large ABC project on Interstate 93 in 

Medford, Massachusetts (also known as the Fast 14). 

I-93 carries approximately 190,000 vehicles per day on 

8 lanes of highway (4 in each direction). The project 

involved the replacement of 14 bridge superstructures 

(41 spans). The time required to replace the 

superstructures using conventional staged construction 

was determined to be 4 years. The impacts to local 

businesses and the greater Boston metropolitan area 

would be significant. The DOT investigated the use of 

detours and ABC in order to reduce the overall 

timeframe for the project. Three levels of detours were 

investigated. The first involved shifting traffic on to the 

two beltways that surround Boston. Vehicles traveling 

through the Boston area can be diverted onto these 

beltways through the use of interstate variable 

message signs. The second level of detours involves 

the reduction of two travel lanes on the interstate in 

each direction on weekends, corresponding to a 

reduction in capacity of 50 percent. Median crossovers 

were used to detour bi-directional traffic to one side of 

the interstate, thereby freeing up an entire 4 lane area

for construction. The third level of detours involves the 

use of local roads around the construction site. These 

will be used for spill over traffic that cannot be 

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accommodated on the reduced capacity interstate, and 

for local residents that sometimes use the interstate for 

short trips across town. 

This approach allowed for the complete closure of one 

direction of I-93 for a 55 hour weekend period. Using 

this approach, the DOT developed an ABC approach 

that was able to replace up to 6 spans per weekend. 

This was done using prefabricated modular 

superstructure elements. On Monday morning, the 

entire interstate was re-opened to 8 lanes of traffic. 

The resulting construction impacts to I-93 were

reduced from 4 years to 10 weekends. Construction 

for this project was completed during the summer of 

2011.

The DOT instituted a significant public outreach effort 

as part of this project. Local businesses as well as the 

central Boston businesses agreed that the short 

duration severe impact would be preferable to the longterm construction option. In fact, the impacts to the 

greater Boston area were negligible during 

construction, due in part to the success of the traffic 

management approach and public outreach.

Construction Staging

In some cases, no viable detours are available. This 

may be due to poor capacity, poor geometry, or the 

overall length of the proposed detour. Bridges in rural 

areas often fall into this third category, where the 

detour lengths can be many miles. In these situations, 

construction staging may be the only viable option. 

ABC techniques are still appropriate for these 

situations. ABC can be used to reduce the duration of 

each stage, and thereby the entire duration of the 

project. 

Construction staging can have a significant cost effect 

on a project. Staged construction inevitably results in 

lower production rates for all aspects of construction. 

Removal and delivery of materials is more difficult, and 

additional safety feature are required to provide a 

secure work zone. Even with these measures in place, 

the work zone for a staged project is much more 

dangerous when compared to a complete road closure. 

The cost of construction staging should be weighed 

against the potential extra cost for ABC. 

Temporary Bridges

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In some instances, the use of construction staging or 

detours is not viable. This can be due to factors such 

as project site constraints or the structure type. 

The use of temporary bridges should be a last resort 

traffic management option. The time required to 

construct a temporary bridge further extends the 

overall project construction timeframe. Also, the cost 

of the temporary bridges and approaches is significant. 

In some cases, the temporary bridge cost can 

approach 50 percent of the final bridge costs. These 

factors should be carefully weighed against the time 

savings and potential extra cost for ABC.

3.2.1.4. Right of Way Issues 

ABC projects often necessitate temporary right of way 

beyond the proposed transportation facility. Staging yards 

on agency owned right of way are not always available. If 

the design team chooses a lateral skidding/sliding method, 

temporary right of way adjacent to the bridge may be 

necessary. The design team needs to identify the 

following right of way parameters as a minimum:

• Is there available right of way for a staging yard 

near the bridge site? If not, is there potential for a 

short term lease of land for this purpose?

• Is there available right of way for crane locations 

near the bridge site? If not, is there potential for 

short term construction easements?

• Is there available right of way adjacent to the 

bridge?

3.2.1.5. Utilities

Utilities both above ground and underground are present 

on many bridge sites. These can have a significant impact 

on the methods of construction that are feasible for the 

site. The impact of the utilities on the installation of 

prefabricated elements and systems can be significant. 

Overhead wires can obstruct crane operations; however 

this can sometimes be overcome through the use of gantry 

cranes, which require lower headroom and SPMTs that 

move elements at levels that are just above the level of the 

bridge. In most cases, it is desirable to remove overhead 

utilities from the site, either by temporary or permanent 

relocations. 

Underground utilities can be left in place in many cases, as 

long as the utilities are not affected by excavations and 

foundation installations. Construction loads can be 

accommodated with steel plates or crane mats.

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Agencies should consider relocation of utilities in a 

separate pre-construction contract. This will eliminate 

potential delays during construction caused by utility work.

3.2.1.6. Local Government Constraints

It is important to open a dialog with the local governments 

for any construction project. The community impact of a 

construction project can be significant. Project planners 

should meet with local governments to identify any 

constraints that may be applicable to the project. For 

instance, the construction may impact the traffic access for 

a local festival. Detours or lane restrictions can greatly 

limit the success of these events. ABC can be used to 

complete projects, or stages of projects before community 

events. 

School bus routes are often cited by local governments as 

a point of concern. Even small detours can have a 

significant impact on bus routes and schedules. These 

impacts should be identified and explored during the 

project planning process. In some cases, agencies have 

used ABC to complete entire bridge projects during 

summer recess in order to avoid school bus route impacts.

3.2.1.7. Structure Type Options

Most bridge construction projects include a structure type 

study. The goal of most type studies is to find the lowest 

cost option with a given set of parameters. ABC project 

differ from this traditional approach. Different ABC 

methods may favor certain bridge types. This is especially 

true for foundations and substructures. If a reconstruction 

of a bridge is planned to be built on the same footprint as 

the existing bridge, the construction of the foundations and 

substructures may result in a slow construction process. In 

this case, building the new foundations and substructures 

around the existing substructures should be investigated. 

This will have an effect on the span layouts, foundation 

types, and substructure configurations. 

For example, several bridges have been designed and 

built with large diameter drilled shafts installed outboard of 

the existing bridge prior to the closure of the bridge. Once 

the existing bridge is closed and removed, a precast cap 

beam can be installed between the drilled shafts. Figure 

3.2.1.7-1 shows this sequence of construction.

It is also possible in some cases to install drilled shafts and 

micropiles under existing bridges. There is equipment that 

is specifically designed to work in low headroom situations. 

This also opens up the opportunities to install the deep 

foundations prior to roadway closure.

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On many highway overpass bridges, the abutments are 

perched on top of the approach embankments. In this 

situation, it may be possible to construct the new abutment 

in front of the existing abutment prior to roadway closure 

using cast-in-place concrete. 

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Figure 3.2.1.7-1 Construction of Drilled Shafts

(Prior to Removal of the Existing bridge)

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The following considerations should be made during the 

structure type study phase of the design:

• What is the most feasible structure type for the 

site?

• What other structure types are reasonable?

• For replacement projects, are there foundation and 

substructure types that can be installed on a 

different footprint prior to removal of the existing 

bridge?

3.2.2. Flowcharts for Determination of Appropriate ABC Methods 

The characteristics of each bridge site identified in the previous 

sections will have an impact on the viable ABC methods that can 

be used. In many cases, multiple ABC methods will be 

acceptable. 

The following pages contain flowcharts that have been developed 

to identify the most appropriate ABC method for a particular site. 

A project development team can run through the flow charts with 

the available site constraints and determine the most appropriate 

ABC methods.

These flowcharts, which are shown on the following pages, cover 

the most common bridges; however they will also be a good 

starting point for more complex bridges. The intent is to steer 

design teams in appropriate directions based on past experience. 

Separate charts have been developed for the following scenarios:

 Figure 3.2.2-1 Superstructure Construction over Roadway or 

Land

 Figure 3.2.2-2 Superstructure Construction over Railroad or 

Transit

 Figure 3.2.2-3 Superstructure Construction over Waterway or 

Wetland

 Figure 3.2.2-4 Substructure Construction

Note: Construction with individual prefabricated elements is 

appropriate and should be considered for all sites. 

Construction time for these systems can be as fast as 3 

weeks for a single span bridge and 4-5 weeks for a typical 

two span overpass bridge. For more complex sites, 

alternate ABC methods may be more appropriate. For 

example, if traffic management requires a replacement to 

take place in 2 weeks, a more complex ABC method such 

as an SPMT move may be more in order.

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Legend

Site Description

Question 

and

Decision 

Conclusion ABC Technique 

Recommendation

Figure 3.2.2-1: Decision Flowchart for Superstructure Construction over Roadway or Land

140
Legend

Site Description

Question 

and

Decision 

Conclusion ABC Technique 

Recommendation

Figure 3.2.2-3: Decision Flowchart for Superstructure Construction over Railroad or Transit

Federal Highway Administration Accelerated Bridge Construction Manual 

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Legend

Site Description

Question 

and

Decision 

Conclusion ABC Technique 

Recommendation

Figure 3.2.2-3: Decision Flowchart for Superstructure Construction over Water or Wetlands

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Legend

Site Description

Question 

and

Decision 

Conclusion ABC Technique 

Recommendation

Figure 3.2.2-4: Decision Flowchart for Substructure Construction

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The pooled fund study that is underway at the Oregon Department 

of Transportation will include similar decision processes. 

3.2.2.1. Example Project

The following is a sample hypothetical bridge project that 

will be used to demonstrate the use of the flowcharts. The 

basis for this hypothetical project is a bridge that was part 

of the FHWA Accelerated Construction Technology 

Transfer workshop projects. The project was located in 

Helena, Montana. Minor details regarding the site will be 

modified in the hypothetical situation.

Project Description:

The project consists of the replacement of an 

existing 4 span bridge. 

Bridge Description:

The bridge carries two lanes of a local road over an 

Interstate Highway. Figure 3.2.2.1-1 shows an 

elevation of the existing bridge. The bridge is in fair 

to poor condition.

Overpass Roadway Description:

The land surrounding the bridge site has been 

under development in recent years. There are 

several large retail stores near the bridge site. The 

road is a two lane road with narrow shoulder and 

no sidewalks. The roadway geometry is favorable; 

therefore, no significant geometric changes are 

required. The traffic volume is expected to exceed 

the design capacity in the near future. There is a

need to widen the roadway to four lanes with two 

sidewalks.

Lower Roadway Description:

Figure 3.2.2.1-1 Existing Bridge Elevation

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The road under the bridge is an Interstate Highway. 

Traffic volumes are not excessive.

Traffic Management:

The roadway carried by the bridge has high ADT. 

There is a detour; however it will have a significant 

impact to traffic traveling to and from the retail 

stores. Following several public meetings, and 

meetings with the local retailers it was decided that 

a long-term staged construction project was not 

desirable. A short-term detour would be acceptable 

if the roadway closure time was kept short.

Land Availability:

The land adjacent to the bridge approaches is 

scheduled for retail development and is not 

available for a staging area. The low volume of 

traffic on the interstate is conducive to construction 

over traffic during low volume hours.

ABC Decision Making Process

The agency used an ABC Decision Making 

Flowchart to determine if ABC was appropriate for 

the project. The traffic management requirements 

and the impact to the local retail stores led the 

agency to decide to move forward with ABC.

Preliminary Structure Type:

Several Structure Types were investigated. There 

was a desire to eliminate the two piers adjacent to 

the low speed lanes of the interstate. This would 

allow for future widening of the interstate. The 

structure type chosen for the replacement is a two 

span continuous weathering steel girder bridge with 

a composite concrete deck. The substructure will 

consist of integral abutments and an open frame 

pier bent supported on a spread footing.

Evaluation of Appropriate ABC Methods using Flowcharts

The following pages contain the previously 

illustrated flowcharts with the decision path outlined 

in red. Figure 3.2.2.1-2 shows the flowchart for the 

superstructure, and Figure 3.2.2.1-3 shows the 

flowchart for the substructure.

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Figure 3.2.2.1-2 ABC Flowchart for Example Bridge Superstructure

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Substructure element 

construction

Is the project a 

replacement of 

an existing 

bridge? 

No

Yes

Yes

Can the new 

substructure be 

laid out in a new 

footprint under 

bridge? 

Is there room to 

install new 

foundation and 

substructure 

before removal of 

bridge? 

No

Substructure construction 

prior to bridge removal is 

not viable

Consider construction in 

place prior to removal of 

existing bridge

Yes

No

Consider construction in 

place with pre-fabricated 

elements after bridge 

removal

Can the new 

bridge be built 

on a new 

alignment? 

Consider construction 

in place with prefabricated elements

No

Yes Is it feasible to use 

a full width cap 

beam supported on 

outboard 

foundations?

Yes

Consider using outboard 

foundations with prefab. 

cap installed after bridge 

removal

No

Can a shallow 

foundation be 

used?

(Low or no scour) Consider Geosynthetic 

Reinforced Soil 

Integrated Bridge 

System

Consider construction 

in place with prefabricated elements

Yes

Can a shallow 

foundation be 

used?

(Low or no scour) 

Consider Geosynthetic 

Reinforced Soil 

Integrated Bridge 

System

Yes

No

Consider Geosynthetic 

Reinforced Soil Integrated 

Bridge System

Can a shallow 

foundation be 

used?

(Low or no scour) 

No

Yes

Consider rapid 

embankment 

construction 

(geofoam)

Consider rapid 

embankment 

construction 

(geofoam)

No

Figure 3.2.2.1-3 ABC Flowchart for Example Bridge Substructure

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Discussion on the Superstructure Flowchart Results

The superstructure flowchart shown in Figure 3.2.2.1-2 

shows the decisions that were made by the design 

team (in red). 

The first question asks if there was a nearby area for 

superstructure prefabrication. As previously stated, the 

land near the bridge is scheduled for development; 

therefore it could not be used for a staging area. This 

led to the conclusion that offsite superstructure 

prefabrication was not viable.

The next question asks if there was room adjacent to 

the bridge for superstructure prefabrication. A review 

of the photo in Figure 3.2.2.1-1 shows that there is 

ample room for prefabrication of the superstructure 

adjacent to the bridge. The traffic on the interstate 

highway is also light; therefore the erection of beams 

and placement of concrete should not have a 

significant impact on the traveler on the interstate.

The next question asks if there is a travel path between 

the prefabrication site and the new bridge. The design 

team determined that there is ample room in the 

median and shoulder to construct either an SPMT 

travel path or to construct a lateral sliding frame.

The result of the flowchart exercise is that there are 

three potential ABC options.

1. Construct the superstructure on false work 

adjacent to the existing bridge and move it into 

place using SPMTs

2. Construct the superstructure on false work 

adjacent to the existing bridge and move it into 

place using lateral sliding/skidding equipment.

3. Construct the superstructure in place using 

prefabricated elements (beams and precast 

deck)

The third option is always viable since it most closely 

replicates conventional construction. The difference is 

that the cast-in-place concrete pours are replaced with 

precast concrete elements, which reduces overall 

construction time. 

Discussion on the Substructure Flowchart Results

The substructure flowchart shown in Figure 3.2.2.1-3 

shows the decisions that were made by the design 

team (in red). 

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The first question asks if the project involves the 

replacement of an existing bridge. The answer is yes 

in this case.

The next question asks if the bridge could be built on a 

new alignment. The design team determined that there 

was insufficient right of way adjacent to the bridge site 

to re-align the roadway; therefore the answer was no.

The next question asks if the new substructure could 

be laid out in a different footprint than the existing 

bridge. The proposed structure is a two span bridge. 

The proposed center pier will be in the same location 

as the existing pier. It may be possible to construct the 

new abutment in front of the existing; however the 

integral abutment stem would be too tall and pile 

installation would not be possible. For these reasons, 

the design team decided that the new substructures 

would at least be in partial conflict with the existing 

substructure. Therefore, the answer to the question 

was no.

The next question asks if it was feasible to use a full 

width cap beam supported on outboard drilled shafts. 

The design team decided that this was not feasible 

since the proposed structure would be very wide (four 

lanes, shoulders, and sidewalks). Therefore, 

substructure construction prior to removal of the 

existing bridge is not feasible; however other ABC 

methods for substructure construction are still viable.

The next question asks if a shallow foundation can be 

used. The answer is yes. This provides two potential 

solutions for the construction. The first is the use of the 

GRS IBS technology. The FHWA technology team has 

not yet recommended that this technology be used for 

multi-span bridges due to concerns about differential 

settlement; therefore this technology is not 

recommended. Therefore, the result of the flowchart 

exercise is that there is only one potential ABC option 

for the substructure:

Construct the substructure in place after removal of 

the existing bridge using prefabricated elements.

Final Construction Choices

The result of this exercise is that ABC is viable for the 

site and an acceptable solution was found. The design 

team chose to close the roadway over the interstate 

and establish a short term detour. 

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Construction would be accelerated by building the new 

superstructure on false work prior to bridge closure. 

This would have no disruption to the heavy traffic on 

the overpass roadway, and limited disruption to the 

traffic on the interstate highway. Once the 

superstructure is complete, the detour will be put in 

place and demolition of the existing bridge will take 

place. Precast concrete elements will speed up the 

construction of the substructure to approximately 4 

weeks. Installation of the superstructure can then

follow in several days. Total roadway closure time for 

this hypothetical project is approximately 5 weeks.

3.2.3. Structure Type Selection Analysis Including Overall Project Costs

Once armed with the information outlined above, the designers 

and planners can now investigate the various options in order to 

determine the most appropriate approach for the construction of 

the bridge. Every agency will place different emphasis on the 

various aspects of the project. For this reason, hard and fast 

rules will not apply. The following sections contain general 

information on the typical aspects of the final project planning 

process.

3.2.3.1. Cost Evaluation

In many cases, multiple options for construction will be 

viable. The design team needs to identify all viable options 

and study the cost impact of the project. Traditional project 

cost estimating and decision making only accounts for the 

cost of the construction items. Many agencies are now 

accounting for other non-project costs in the project 

planning process. 

During recent FHWA summit meetings for the “Every Day 

Counts” initiative, one of the primary concerns expressed 

by agencies regarding ABC was the higher cost for 

construction. To date, most ABC projects have resulted in 

higher bid prices. The major factors that affect the cost 

differential are the complexity of the project and the 

severity of the time constraints imposed on the contractors. 

Based on the cost analysis of eight bridge projects built 

under the Highways for Life (HfL) program, the additional 

cost premium for deploying ABC was found to range 

between 6 and 21% when compared to the cost estimates 

of traditional construction. In some projects, the use of 

ABC may result in reduced cost premium or overall cost 

savings by eliminating the need for certain construction 

requirements associated with traditional methods. For 

example, in the bridge replacement project of MD 28 over 

Washington Run, the use of ABC resulted in eliminating 

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the additional expenses of constructing temporary bridges 

to maintain traffic flow.

Some agencies that have expressed concerns over cost, 

indicate that they do not see a need to spend extra funds 

to minimize impacts to the public. In fact these agencies 

are already spending additional funds for this purpose. 

Most agencies employ phased (staged) construction in 

order to keep traffic flowing through a work zone. It is well 

know that this construction method is more expensive than 

construction with a full road closure. The contractors are 

required to work in a small work zone with adjacent traffic 

that impedes the work in progress. This approach can 

increase the cost of the construction. ABC/PBES allows 

owners to take reductions in traffic impacts to the next level 

by providing even better customer service. In some cases, 

it may be preferable to close the roadway, establish a 

detour and build the bridge quickly using ABC/PBES. The 

additional costs for this process may very well be offset by 

the elimination of phased construction costs.

As more ABC projects are built, the costs for construction 

are trending downward. This is due to contractor familiarity 

with the process, which results in lower risk. Contractors 

have noted that risk equates to higher cost. Consistency in 

design and detailing will lead to less risk to the contractors, 

which leads to lower construction costs.

The most applicable analogy to this is the development of 

prestressed concrete during the latter half of the 20th

century. Initial costs for prestressed concrete beams were 

inevitable higher than cast-in-place concrete construction 

in the 1950’s. The use of prestressed concrete beams 

required specialized fabrication techniques, and large 

cranes for lifting and placement of the beams. There was 

also a loss of revenue for the general contractors since the

construction of the beams would be handled by a third 

party (the fabricator). As time went by, contractors 

become more familiar with the material and the prices 

came down. Today, most agencies and contractor would 

not consider cast-in-place concrete for concrete bridge 

girders. 

Similar analogies can be applied to items such as color 

televisions, microwave ovens and personal computers. 

The key to reduction in costs is the consistent use of the 

technology with an avoidance of “one of a kind” projects. 

Standardization of details and the incorporation of a 

program of projects into an agency plan will help to reduce 

project costs. A program of ABC projects will send a clear 

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message to contractors that the investment in training and 

equipment is well worth the effort. 

The use of ABC is very similar to the prestressed concrete 

analogy. Contractors are unfamiliar with the ABC process 

and the equipment used on many of these projects. There 

is also a concern by general contractors regarding the loss 

of revenue for field crews as they substitute precast 

concrete for cast-in-place concrete. There are potential 

solutions to this concern that are being explored by some 

agencies. They are considering allowing prefabrication by 

general contracts. The contractors are required to 

establish a quality control programs that mimic plant 

production programs. This alleviates some of the 

contractor concerns over ABC and puts more control over 

the final product with the general contractor.

Another potential scenario is that general contractors will 

focus their efforts more on roadway construction and apply 

less emphasis on bridge building. Sub-contractors or 

teams within general contracting companies specializing in 

the installation of prefabricated elements could potentially 

become more common. These teams could, in theory, 

move from project to project, thereby making the most 

efficient use of the equipment needed for construction of 

prefabricated bridges.

On ABC projects, the least expensive construction cost 

may not result in the lowest total construction cost. The 

cost for various ABC techniques needs to be factored into 

the total cost of the bridge. The cost for ancillary items 

such as railroad flagging, police details, resident 

engineering time, traffic control devices costs, etc. also 

needs to be studied. Many states calculate road user 

costs in order to determine the impact on travelers. This 

may also be a factor in deciding the most appropriate 

structure type. It is recommended that all reasonable 

structure types and the associated ABC costs be studied 

for each project. 

The following sections contain information on different cost 

factors that are being used during the project planning 

process.

Time and Materials Estimating

Most state agencies use a unit price approach to 

estimating construction projects. This approach is 

easy for engineers since it combines the cost for time, 

equipment, manpower, and materials, general and 

project-specific overhead, contingency, and profit. This 

approach works well for conventional projects that 

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have similar constraints. Unusual project constraints 

place a higher premium on man-power and equipment. 

For instance, the forming and stripping of forms on a 

bridge over a railroad will take more hours than a 

bridge over a rural road. The time frames for work 

crew to access the formwork will be limited on the 

railroad crossing and virtually unrestrained on the 

roadway overpass.

In order to evaluate different construction strategies 

(including ABC), it is necessary to approach the 

estimating of the project through the use of cost-based 

estimation. This is sometimes referred to as “bottom 

up estimating”. This approach requires a careful 

examination of production rates, equipment needs, and 

man-power needs for each construction operation. 

Estimators will need to identify unit costs for 

equipment, as well as production rates for specific work 

tasks. Experienced construction management 

personnel should be advised for recommendations on 

these factors.

A cost-based estimate should be calculated for each 

construction option being investigated. This approach 

will help to identify the increased costs associated with 

limited access at a site and the reduced costs 

associated with a site that is closed to traffic. By using 

this type of estimating, a design team can evaluate 

different strategies such as staged construction versus 

full closure combined with a detour and ABC. 

Road User Costs (RUC)

The New Jersey Department of Transportation defines 

road user costs as follows: 

“Road User Costs in the work zone are added vehicle 

operating costs and delay costs to highway users 

resulting from construction, maintenance, or 

rehabilitation activity. They are a function of the timing, 

duration, frequency, scope, and characteristics of the 

work zone; the volume and operating characteristics of 

the traffic affected; and the dollar cost rates assigned 

to vehicle operations and delays” [4]. 

Road user costs represent the incremental cost borne 

by the road users and the society at large as a result of 

the construction of the bridge. It typically refers to 

monetized components of mobility, safety and 

environmental impacts resulting from the work zone 

activities. It also helps to quantify the impact of bridge 

construction and nearby construction projects, if any, at 

a corridor level.

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FHWA is preparing a practitioners guide for estimating 

work zone road user costs. This document provides 

step-by-step approach to calculate key components of 

work zone RUC, and presents a discussion on input 

needs and available tools. There are several tools 

available to compute these costs.

Several state departments of transportation have 

developed spreadsheet-based tools for RUC 

computations. Examples include the New Jersey 

DOT’s road user cost spreadsheets, Michigan DOT’s 

CO3, and Maryland SHA’s Loss of Public Benefit 

(LOPB) tool. 

The 2010 Highway Capacity Manual [57] provides an 

analytical basis for estimating work zone traffic 

impacts, a key component of the road user cost model. 

Some agencies have not incorporated the study of 

road user costs during the project planning process. 

There is a concern that they should not spend extra 

money to reduce road user costs. The fact is that 

virtually all agencies already spend extra money on 

construction project in order to reduce user impacts. It 

is well known that the cost of a bridge construction 

project is lowest when there is not traffic to maintain. 

Typical approaches to maintenance of traffic are the 

use of staged construction and temporary bridges. 

Both of these options result in increased project costs, 

which is well justified by the need to keep traffic moving 

through a work zone. Therefore, agencies are already 

spending more to reduce user impacts. The goal of 

ABC is to take this approach to the next level. By 

potentially spending a little more, the impacts to 

roadway users can be dramatically reduced through 

the use of ABC technologies.

Regardless of the actual level of financial impacts to 

the traveling public, road user costs can be significantly 

reduced through the use of ABC and PBES. The value 

of road user costs on a particular project may be 

debatable; however the benefits of ABC when applied 

to road user costs are obvious. ABC can be used to 

reduce the mobility, safety and environmental impacts 

of work zone activities by reducing the overall duration 

of the project while the road user quantifies the benefits 

of shorter construction duration and reduced work zone 

exposure. The cost premium of using ABC is offset 

partially or fully by the gains in work zone road user 

costs. 

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Therefore, the agencies are encouraged to account for 

road user costs in the decisions making process for all 

projects to evaluate the economic efficiency of various 

construction options. The total project cost is the 

construction cost combined with the road user costs. A 

return-on-investment (ROI) analysis can be conducted 

by comparing the costs (i.e. increase in construction 

costs) with benefits (i.e. savings in road user costs 

through shorter construction time) for various 

construction options considered in the decision making 

process. 

The HfL ROI analysis measures the economic 

efficiency of an option using its total project cost, which 

is the sum of construction and road user costs. The 

economic analysis of four HfL bridge projects showed 

immediate net savings of 8 to 65% in total project 

costs, thus justifying the use of ABC against traditional 

construction methods [62]. By taking this approach, the 

agency can provide the best value to the traveling 

public.

Maintenance of Traffic Costs

Various construction methods will require different 

maintenance of traffic approaches. The three most 

common approaches for maintenance of traffic on 

bridge replacement projects include, traffic control (e.g. 

staged construction, detours or temporary bridges), 

traffic control devices (e.g. signs and markings), public 

information campaigns (e.g. information centers and 

511 traveler information), operations management (e.g. 

signal timing improvements and traffic restrictions), and 

law enforcement strategies. The maintenance of 

traffic strategies are selected based on the severity of 

work zone impacts and project significance. 

All of the approaches come at a cost to the overall 

project. It is relatively easy to calculate the cost for 

items such as barriers, signs and even temporary 

bridges. The difficult cost to calculate is the loss of 

productivity for crews working adjacent to and 

sometime in between live traffic. Numbers higher than 

50% have been discussed; however there are few 

published studies on the actual cost for work within an 

active roadway. Individual agencies can study these 

costs by comparing the actual cost of similar sized 

projects that were built with different traffic 

management approaches. From this, the general 

premium on traffic management can be determined.

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When comparing the total project cost for an ABC 

project, the design team should factor in the cost for 

traffic maintenance into the overall project cost. In 

many cases, the extra cost for ABC can easily be 

mitigated through the reduction in traffic management 

costs and loss of production at the site.

Safety Costs

Providing a safe work environment is always a priority. 

The various ABC methods described in this manual 

provide a different level of safety. In all cases, the 

reduction in construction time will inevitably reduce the 

exposure time and associated safety risks for both 

workers and motorists. Safety costs quantify the cost 

differential of exposure times associated with various 

construction options. These costs are estimated by 

taking into account the crash history (i.e. crash 

frequency and severity), exposure times (i.e. time of 

day when the work is performed and the number of 

work days), and maintenance of traffic strategies (e.g. 

safety features installed in the work zone). The HfL 

demonstration project reports illustrate the computation 

of work zone safety costs [63]. This cost differential 

should be incorporated into the final decision process. 

Agency Construction Engineering Costs

One very large cost that is not normally included in the 

project planning process is the cost to the agency for 

construction management. In most cases, the 

construction management costs exceed the cost for 

design. Typical agency costs include labor costs for 

inspectors and resident engineers, rental of 

construction offices and law enforcement costs. Most, 

if not all of these costs are not included in the bid 

results.

ABC can be used to reduce agency’s construction 

engineering costs by reducing the overall site 

construction time. With the use of prefabrication, there 

will be more cost for plant inspections; however these 

costs are intermittent and normally much less than full 

time construction staffing.

The agency’s construction engineering costs should be 

studied during the project development process. Any 

savings in agency costs should be included in the final 

decision making process.

Life Cycle Costs

Life cycle cost analysis is a subject in itself that will not 

covered in great detail here. The intent is to focus on 

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how prefabrication can be used within the context of a 

life cycle cost analysis. The FHWA has a website 

devoted to life cycle cost analysis. It can be found at: 

www.fhwa.dot.gov/infrastructure/asstmgmt/lcca.cfm. 

The quality of plant produced product is well 

recognized as being of higher quality when compared 

to field produced elements. There are several reasons 

for this increase in quality.

First, the quality of precast concrete can be better than 

site cast concrete. Prefabricated elements can be built 

in a controlled environment. The control of 

temperature and reduction in weather exposure 

normally result in higher quality concrete product. The 

quality of plant produced concrete mixes can also be 

controlled better since the concrete does not need to

be trucked to a construction site.

The second added benefit to precast concrete is that 

the elements are cast in an un-restrained condition. In 

cast-in-place construction, concrete is often placed 

against previously cast concrete. As the new concrete 

cures and shrinks, cracking commonly occurs. 

Designers try to mitigate this issue with the 

incorporation of control joints and expansion joints; 

however, it is inevitable that some cracking will occur. 

The issue of cracking in bridge decks is widespread 

throughout the United States. Precast elements and 

precast bridge deck panels in particular are allowed to 

cure and shrink in an unrestrained condition, thereby 

reducing, and in most cases, eliminating shrinkage 

cracking. The reduction in cracking eliminates one 

avenue for water infiltration and long term deterioration 

of the concrete.

The increase in quality inevitably leads to an increase 

in service life. This leads to reduced life cycle cost for 

the bridge since the structure can remain in service for

a longer period of time. Many agencies are starting to 

investigate sustainability in bridge construction. The 

increase in service life will reduce the need to replace 

bridges in the future, which is a major factor in 

sustainable construction.

Inflation Costs

Inflation has a significant effect on the cost of long-term 

construction projects. Contractors need to account for 

inflation during the bid process, because the cost of 

materials and labor will potentially increase over time. 

The difficulty with long-term projects is that the 

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estimation of future inflation becomes more uncertain. 

In these cases, contractors normally use higher 

estimated costs in order to cover the potential of future 

inflation. 

Some agencies build inflationary escalation factors into 

major bid items in order to reduce the amount of 

inflationary risk at the time of bid. Escalation factors 

can cover material cost fluctuations; however labor 

cost escalations are not covered. Escalation factors 

can lead to lower initial bid prices, but the overall 

project cost can still be affected by inflation.

ABC can be used to reduce the inflation effects on both 

the bid and inflation escalation factors. By reducing the 

time for construction, the potential impact of inflation is 

reduced. Contractors bidding on projects will have less 

uncertainty during development of the proposal, and 

inflation escalation factors will have less impact on the 

overall final cost of the project.

3.2.4. Public Involvement

Public involvement is a part of the NEPA process for all projects. 

Public involvement process can take on several levels. In early 

project planning, public meetings may be required to help define 

the problem and identify issues that need to be addressed. The 

goal of this preliminary process is to identify the stake holders and 

their needs. On ABC projects, it may be necessary to include an 

additional public involvement process prior to and during 

construction. 

 

Once a decision has been made on the preliminary structure type

and construction methods, a more significant process of informing 

the public can take place. The agency can present all of the 

factors that were used to determine the project approach. This 

form of transparency is often well received and is mandated by 

many agencies. 

Each agency will place a different level of emphasis on the public 

involvement process. More densely populated areas will require a 

more diverse public involvement process. The need to keep the 

public informed drives the level of effort. For instance, in a low

population area, mailings to local residents combined with a public 

meeting may be adequate. In complex urban environments, the 

public involvement process can expand to multiple media formats, 

multiple public meetings, meetings with local officials, and in some 

cases meetings with out of state agencies. This is just a partial 

listing of the possible public involvement process.

Public involvement is critical to the success of an ABC project for 

several reasons. In many cases, an ABC project will create a 

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short-term acute impact to travelers, businesses, and residents. 

Informing these stakeholders will ensure proper public support 

and reduce problems during construction. It is important to be upfront and clear on the impacts of the project. For instance, if 

around-the-clock construction work is scheduled for a residential 

neighborhood, the residents should know that it will be noisy and 

during the night. They should also know the benefits of ABC and 

that the noise will be for a short duration. 

The second way that public involvement can be used for ABC is to 

foster good will among the traveling public and local residents. 

Section 1.2.2 of this manual showed described how the Utah DOT 

gathered information on public opinion of ABC projects. UDOT 

places significant emphasis on the public involvement process for 

all ABC projects, which they cite as one reason for the success of 

their program. 

The bridge design and construction industry has been lax about 

promoting our efforts and celebrating our achievements. ABC is 

an opportunity to show that the ABC is not business as usual and 

that agencies can make a reduction in impacts to travelers and 

local communities.

Many agencies have public involvement manuals and processes. 

The FHWA document entitled “Public Involvement Techniques for 

Transportation Decision-making” [10] is recommended as a 

source for information on the development of a successful public 

involvement process.

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Chapter 4 Implementing ABC in a Transportation Agency

(A Case Study from the Utah DOT) 

Many states have experimented with ABC on individual projects, and some have begun 

a program of ABC projects, but only one agency has implemented ABC as standard 

practice. During the build-up to the 2002 Winter Olympics, the Utah DOT used ABC to 

complete several projects within the time leading up to the event. The success and 

popularity of ABC encouraged the state to move toward making ABC standard practice 

for all bridges. In 2010, the state met that goal. Today, ABC is considered on all bridge 

projects and used where appropriate, with road user costs and innovation driving the 

decision process.

This chapter outlines the approach that was used to implement ABC in Utah. All aspects 

of this approach may not work in every agency; however the general approach is a good 

roadmap to a successful implementation of ABC. 

4.1. General Approach: No Magic Bullet

What follows is a general approach for implementing an ABC program. It 

would be a simple thing to replicate the Utah Department of 

Transportation success in this area, if the formula for doing so was readily 

available. For those who wish to find the simple solution, what may they 

find that is contained in this chapter will be disappointing. For it is a 

complex matter to implement a change of such magnitude. What is 

required beyond the fortitude, is a multi-faceted, multilayered, complex 

weave of activities, some small, some large and some bold, all with the 

singular purpose of driving both the agency and the industry within the 

state to change.

What follows are some of the activities that UDOT undertook to 

implement ABC. In one post-implementation exercise, where UDOT staff 

was asked to compile all of the activities that they had undertaken to 

implement ABC, they brainstormed 43 separate efforts that supported 

implementation. What follows are some of the most important activities. 

What is not guaranteed is that by doing so, by practicing these activities 

that an ABC program will materialize. The truth is that one may do these 

activities and still not be successful. On the other hand, success will 

surely not come, unless one tries. What follows are not guarantees of 

success, but ideas and activities that have led to success in one state. 

Figure 4.1-1 is a sample flow chart for ABC implementation in a state 

agency has been developed based on the text in this Chapter, the Utah 

experience, and the recommendations of the FHWA Every Day Counts 

initiative. The flow chart represents a suggested approach to this effort. 

It is understood that each agency functions in a different manner; 

therefore the approach may need to be modified for each agency. The 

intent is to present the major activities that will help to produce a 

successful ABC program.

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Figure 4.1-1 Sample ABC Implementation Flow Chart for a State Agency

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4.1.1. Strategic Layers of Implementation

As one tries to implement an ABC program, one should keep in 

mind the following idea. In order to be successful, one must 

contemplate that there are different strategic layers of 

implementation. 

A state agency must have a plan for each component, and must 

have multiple sub-strategies. An organizational behavior to watch 

for is the blossoming of spontaneous supporting activities led by 

working units. The state will have planned for two dimensions, 

layers, and depth within layers, and their people will bring forth 

another dimension as implementation proceeds, and as the idea 

gains momentum.

4.1.2. Upper Management and Politics

It is an obvious observation to state that the success of 

implementing ABC is dependent upon the support of upper 

management. There must be communication, and education to 

keep leadership informed and knowledgeable about the status, 

needs, and early successes of the program. A good strategy is to 

establish a regular communication pattern. It is extremely 

important that management be kept in the loop and has 

confidence in what they are being told. The time spent to inform 

and communicate will pay off dividends when problems and 

adversity occur. 

The strategies that work for upper management also work for 

politicians. Politicians can be kept in the loop the same way as 

upper management. This may be a task best accomplished by 

upper management. An ABC champion should talk about 

involving and advising politicians with upper management, and 

they should decide how to proceed. Political and upper 

management support can be gained through careful and honest 

communication. This activity can be seen as the “air war”.

4.1.3. Mid-Level and Organization

There must be a plan to deal with articulating ABC to middle 

management and first level supervisors. The plan must include 

messaging, question and answer sessions, informational 

meetings, and expectations discussed. The plan must provide

middle managers and supervisors with information about why 

ABC is important, and what it will bring to the organization.

Standard messages concerning ABC are:

• ABC decreases impacts to the traveling public: The 

projects may last as long, but the work zones will not 

impact the traveling public as long. ABC is part of the 

department’s effort to stay out of the public’s way.

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• ABC increases the safety of the traveling public, and 

workers: It is obvious that it will be safer for the traveling 

public if works zones and detours are not in place as long. 

What is not as obvious is the safety implications to workers 

and employees. Construction workers and department 

employees will be safer and will be out of harm’s way more 

often.

• ABC has the potential to cost less than current methods: 

Precast elements have the potential to cost less than castin-place methods. Precast girders have long been shown 

to be less expensive than cast-in-place girders. It is 

reasonable to conclude that other precast elements may 

be less expensive than their cast-in-place counterparts. 

• ABC has the potential to deliver higher quality bridges: By 

using manufacturing methods, and constructing pieces in 

controlled environments, other industries have increased 

the quality of end products. It is reasonable to conclude 

that prefabricated elements can be manufactured to be of 

higher quality.

Middle management must be given the opportunity to question

decisions, and in return, be given good reasons for them to 

support a change. They must be given the ammunition they will 

need to convince others. They must also understand that ABC is 

the direction of the future, and that they will be expected to 

support the agency’s decision. This information, the questioning 

and discussions should take place in meetings separate from their 

employees, so that middle management may be free to openly 

communicate and question.

The agenda for these meetings with middle managers should 

include the following: 

• There will be an outline of what the department is planning 

to change, and why they are planning to implement ABC. 

The presentation should include information about those 

that have successfully implemented ABC elsewhere. 

• There should be a discussion of the messages, complete 

with questions and answers. Upper management should 

ask middle management what they see as problems with 

initiating the change, and answer how they plan to 

overcome those obstacles. Upper management should 

have prepared for this question-and-answer session with 

what they perceive to be frequently asked questions. For 

those obstacles that do not have an immediate answer, 

upper management should ask middle management how 

they would suggest solving that issue. If there are no 

obstacles presented that couldn’t be answered readily, 

then upper management should still ask the questions: 

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What does middle-management intend to do to help 

implement this effort? What resources do they need, what 

organizational changes will they make, and what will the 

future look like with ABC implemented? This part of the 

meeting will help build momentum and organizational 

alignment. 

• The last part of the meeting will be spent in discussing rollout sessions with the rest of the organization. Upper 

management should ask middle management to conduct 

meetings whereby employees are informed and educated 

concerning the roll-out effort for implementing ABC. 

• The last part of the meeting with middle management will 

set schedule and agenda for these employee roll-out 

meetings.

This strategic communication plan, involving middle-management, 

follows the principle of aligning the entire organization from top to 

bottom with the messages, and the reasons for the 

implementation of ABC. This careful communication, respectful of 

middle management’s needs to be seen as “in the know”, and as 

leaders, does much to build support in the organization. The 

messages themselves are important, but not as important as 

involving middle management, and giving them the tools they 

need to speak to front-line employees. 

4.1.4. Project Level

The mid-level managers and supervisors should communicate

information to employees concerning ABC implementation. As 

stated earlier, the plan should include meetings conducted by 

middle management to roll-out ABC to the employees. Middle 

management must be given the opportunity to deliver the 

messages, answer the questions, and demonstrate support for 

accelerated bridge construction. 

The agenda for the meeting is parallel to the meetings that were 

held between upper management and middle management. The 

same items are discussed. Middle management should present 

the agency’s reasons for implementing ABC including:

• Citing successful implementations elsewhere

• Communicate why the agency is implementing ABC

• Allowance for a question-and-answer session. 

Just as upper management asked middle management for ideas 

concerning implementation, middle management should engage 

employees in those same types of discussions. Middle 

management should ask employees for ideas concerning how to 

implement ABC. 

A difference in these employee meetings will be that middle 

management will ask: What tools are required at the project level 

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to implement ABC? Things like training, realignment of staffing, 

design software, scanning tours, and other tools to help build 

knowledge and commitment at the working level. Middle 

management should carry these requests for resources back to 

upper management.

4.1.5. Identify ABC Champions at All Levels

As ABC implementation proceeds, the agency will be able to 

identify ABC champions at all levels. It is important that these 

champions are given resources, and helped through the process. 

These champions that blossom are a resource to help the 

implementation effort. Management should identify these 

individuals, reward them, and give them what they need to be 

successful. 

4.2. Stakeholder Buy-in

The implementation of ABC requires participation of other important 

stakeholders. ABC implementation should include the following with 

respect to contractors, designers and industry:

• Education and training

• Roll-out meetings

• Leading to understanding and acceptance

Implementing ABC changes the way that contractors build bridge

projects, and requires more industry-generated prefabricated elements. 

The agency should carefully think through their strategy for 

communications and messaging with contractors and industry. 

The state should strive for the support of contractors and fabricators. 

They should be supplied with business reasons, an understanding of 

direction, and an ability to participate in the implementation. Just as with 

middle management and employees, the agency must ask the questions

of contractors: How do we, the construction industry within this state, 

implement ABC? The agency can generate much support for ABC by 

listening to, and acting on these suggestions. 

One of the common problems in implementing ABC is that of training and

education. Contractors, designers and fabricators will have the same 

issues. It will fall to the state to provide training and workshops for 

contractors, designers and fabricators.

4.3. Scanning Tours

One of the most useful implementation efforts is the use of scanning 

tours. Scanning tours are visits to construction sites where successful 

implementation of ABC can be observed. In Utah this took the format of 

visiting states that were more advanced than Utah, and construction sites 

where interesting ABC techniques were being deployed. Utah 

stakeholders visited the state of New York to view their implementation of 

prefabricated elements. They also visited several sites and states where 

SPMTs (self-propelled modular transporters) were being used to move 

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bridges. This activity provided the opportunity to see, and hear directly 

from successful implementers. 

The makeup of the scanning tours included Department personnel, 

Department contractors, Department suppliers, and Department design 

consultants. Utah was able to pay for these trips by utilizing federal SPR 

research funds. There were several positives to the implementation effort 

from these tours. The most significant positive outcome was the 

demonstration that ABC can be done, and that it can be done in standard 

applications and projects.

The scanning tours can build confidence, and almost a sense of 

competition between agencies. One of the most revealing comments 

came from one of Utah’s most successful ABC contractors. Upon seeing 

the nation’s first SPMT move in Florida, the contractor commented “If they 

can do this in Florida, we can do this in Utah”. This contractor went on to 

be one of the first and now one of the most successful ABC implementers 

in Utah.

Other benefits of the scanning tours included the establishment of a 

network for questions. Utah personnel met with other states, and 

developed a communication link with peers in those states. Those same 

peer-to-peer relationships occurred within the consultants, fabricators and 

contractors. The geographical separation between Utah and the locations 

of the scanning tours meant that these relationships and communications 

were non-threatening, and non-competitive financially. This allowed for 

open communication concerning challenges and rewards for

implementing ABC. The scanning tours proved to be one of the most 

often cited, successful, and beneficial implementation strategies.

4.4. Demonstration Projects 

Demonstration projects should be a part of ABC implementation. The 

UDOT used demonstration projects to prove the worth and concept of 

ABC. UDOT used programs such as “Highways for LIFE”, federal 

Innovative Bridge Research and Deployment (IBRD) funding, and federal 

research money to help with implementation of ABC demonstration 

projects. These monies in grants can help the state pay for the increased 

cost of first implementations. Equally as important were the efforts that 

led to the first projects. UDOT spent time and effort to ensure the success 

of these first projects, by choosing good projects, and by allocating 

resources to ensure that the projects went well. Demonstration projects 

play an important role in implementing ABC.

4.5. The Role of Innovative Contracting

Innovative contracting, such as the use of Design-Build (DB) or 

Construction Manager General Contractor (CMGC) can help in 

implementation of ABC (See Section 2.5). On many of the first ABC 

projects, UDOT used innovative contracting methods. For instance, the 

first SPMT project UDOT built was also a CMGC project. The benefits of 

these innovative contracting methods allow for the introduction of these 

new techniques and technologies. 

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CMGC is especially adaptable to ABC with its formation of a design team 

that includes the owner, the designer, and the contractor. In this design 

team the owner can exert and ensure that new technologies are not only 

a part of the contract, but successful. There also seems to be much 

contractor support of innovation when the contractor is in control of the 

risk. Innovative contracting places much of the risk with the contractor 

but also allows him the freedom to innovate and to mitigate risk. The 

observation from viewing UDOT projects is that there is much synergy 

between innovative contracting and ABC projects.

4.6. PBES Decision Making Framework

Another organizational modification that was helpful in promoting ABC

was the adoption by UDOT of a decision-making framework (See Section 

3.1). In UDOT’s decision-making framework there was a process by 

which project managers were asked to consider the use of accelerated 

bridge construction on all projects. The decision making process was 

guided by an organizational theme that favored ABC. The decisionmaking framework implemented by UDOT was instrumental in guiding the 

programmatic adoption of ABC. 

Another component of the decision-making process was a consideration 

of road user costs (See Section 3.2.3.1). Standardization of a road user 

cost model and the process by which road user costs are determined

should be undertaken. A central unit should conduct the modeling, in a 

prescribed manner. Road user costs should be computed in the same 

way for all projects. This standardization of road user cost models also 

helps with the decision-making process and theme that favors ABC.

An outgrowth of the decision-making process was a realization that to 

implement ABC there would need to be a mechanism to recognize this 

early in the project development process and to plan for it within project 

budgets. In the early phases of implementation it was acknowledged that 

ABC would cost more than the traditional methods. It was a department 

policy decision to implement ABC by necessity, and to include these 

costs in early implementation projects.

4.7. Establish a “Program of Projects”

A good strategy for implementing ABC is to plan for a program of 

projects. UDOT established a policy early on that they would not just 

implement demonstration projects, but would announce implementation of 

a program of projects. This strategy helped give contractors and industry 

the business reasons they might need to invest in ABC technologies, 

training and process. Early implementers among contractors and industry 

recognized that they would have a competitive advantage in subsequent 

projects if they were involved in the first projects. This led to great 

competition and great acceptance of the early projects, as contractors 

were jockeying for position.

The announcement of a program of projects also proved to be an 

incentive for UDOT personnel to make organizational changes to adapt to 

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the new normal. The strategy of pursuing a program of projects was a 

signal to UDOT and the entire industry that ABC was a method of the 

future. The strategy has proven to be an accelerant for implementing 

ABC. Another example of this programmatic implementation can be seen 

in Massachusetts’s implementation of ABC. Massachusetts announced 

in 2010 its intent to consider ABC on all projects, and has begun a 

substantial program. This has led to a groundswell of support in their 

industry.

4.8. Develop Specifications, Standards, and Standard Details

Another effective strategy that UDOT employed was the development of

specifications, standards, and standard details for ABC. This effort 

should involve contractors, designers and industry. In UDOT’s case, 

several workshops and convened working groups were conducted to help 

with the development of standards and specifications. UDOT worked 

closely with groups such as Utah Association of General Contractors

(AGC), American Council of Engineering Companies (ACEC) and the 

Precast Prestressed Concrete Institute (PCI). This effort included widely 

distributing draft standards and specifications, and looking to other states 

for examples of details that might work in Utah. Utah also published 

manuals on their website, making it available for comment and use.

This strategy also demonstrated UDOT’s commitment to ABC 

implementation. It is another demonstration that they were heading in the 

direction of an ABC program. This demonstration had positive effects on 

both the UDOT organization, and the industry in Utah.

4.9. Communication

In developing the implementation plan for ABC, UDOT used professional 

communication staff. An implementation plan normally consists of a 

communication plan, a marketing plan, and an organizational plan. 

UDOT employed professionals trained in communications to help develop 

the communications and marketing plans. They found that by using 

careful communication developed by professional communicators, the 

message reached target audiences effectively. 

Professional communicators are especially adept at developing 

messages and helping to deal with the media. If these messages are 

carefully crafted, they will resonate with the media and the public. An 

example of this was a message crafted concerning minimizing the 

impacts to the traveling public. The communication professionals helped 

develop the slogan “From Months to Days”, as a way to describe that the 

impacts of the project would be less. It was interesting to watch as the 

media adopted the message and would say in describing the project that 

literally the process was going “From Months to Days”. These types of 

messages and this type of media attention help to positively improve the 

implementation of the ABC program.

Another portion of the messages developed should be meant for helping 

members of the state executive branch talk about ABC. The agency

should develop ways to communicate the messages and successes of 

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ABC programs. Things such as flyers describing the program could be 

distributed to the legislature and state executive branch.

Another effective outreach would be to local governments and partner 

agencies. The fliers containing messages and facts could be distributed 

widely to help in this educational effort.

There are many other examples of how professional communicators can 

help with the implementation of ABC. They are trained to recognize the 

audience and how to tailor effective communications for those audiences. 

Utah’s ABC program benefited tremendously from the involvement of 

professional communications personnel during the development of the 

plan; and before, during and after the construction of ABC projects.

4.10. Measure and Share Successes

Part of the implementation plan at UDOT was the development of 

measures of success. It was immediately recognized that there were 

certain arguments against ABC and that UDOT would need data and 

examples of success to negate and mitigate these concerns. 

One of the first arguments against implementing ABC will typically be an 

objection to the cost of changing from current practice. UDOT developed 

a series of presentations and slides to help policymakers understand that 

while it may cost more to implement ABC, over time it was hoped that the 

costs would be less than traditional methods. During the implementation 

UDOT tracked this cost information and was able to show confirmation of 

their theory concerning first costs. They were able to show that high 

costs during early projects went down over time as more projects were 

completed and as the industry became familiar with ABC. UDOT was 

able to show that in some cases, costs for ABC bridges are less than 

traditional methods. Perhaps more importantly, they were able to show 

that schedules for ABC projects are faster than projects using traditional 

methods. It is important that agencies implementing ABC collect baseline 

data and that during the implementation, collect data to help explain the 

program and show progress. This interim data collection and sharing can 

be used to help sell the implementation process. 

An agency can also develop information to measure public support for 

ABC. In Utah’s case, their first projects showed overwhelming public 

support for the projects. The public showed support of the speed at 

which the projects progressed, and the innovative methods that were 

used. These opinions had great impact on UDOT’s public support. 

Public support has great ramifications for legislative support and hence 

public funding. Measuring and sharing these statistics has positive 

organizational impacts. Most people like to be on a team that is 

recognized positively. 

Another strategy that was proven to be effective was to invite legislature 

and local politicians to ribbon-cutting opportunities. The public opinion of 

ABC grew, and there was recognition that projects were open to the 

traveling public faster. Politicians were asked to celebrate these projects 

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and to be a part of ribbon cutting ceremonies. These opportunities to 

share in the success of the projects are valuable in helping build 

momentum and in ensuring political support for implementing ABC.

4.11. Conclusions

There are a variety of strategic implementation efforts that can help a 

DOT move forward with ABC. Many foundational change management 

techniques were discussed in this chapter. It is easy to see that these 

techniques work together, and that they require much planning and 

preparation, as well as energy in execution. To implement ABC is a 

journey, not an easily completed trip. 

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Chapter 5 Prefabricated Bridge Elements

There are many types of prefabricated bridge elements in use in the United States. 

Prefabricated elements are used for all components in a bridge. This includes 

superstructures and substructures. The previously published FHWA Manual entitled 

“Connection Details for Prefabricated Bridge Elements and Systems” [3] covered 

prefabricated bridge elements in detail. Some of the content from that manual will be restated in this chapter. Several concepts have advanced following the publishing of the 

connections manual. In these cases, the new information will also be included. 

Proprietary products are normally prequalified by agencies. FHWA has specific 

guidelines on the use of proprietary products. These can be found at the FHWA website 

(www.fhwa.dot.gov/construction/cqit/propriet.cfm). Specifications for proprietary 

products should include, but not be limited to, provisions for the submission of 

engineering and load rating calculations. The requirement for submission of 

maintenance and inspection guidelines should also be a considered by the agency. 

5.1. Materials

This section provides an overview of the many different types of materials 

used in prefabrication and discusses the impact of the materials on 

accelerated construction processes. Most agencies have approval 

processes for prequalification of proprietary materials (i.e. grouts, 

mechanical connectors, etc.). Designers should be aware of the 

materials that are available for use in a particular agency prior to 

specifying the material.

5.1.1. Structural Steel

Steel elements are well suited for prefabrication and accelerated 

construction. There is a high degree of control over fabrication 

tolerances; therefore, complex connections can be employed 

using structural steel. Common elements include steel beams 

and girders, steel grid decks (including concrete filled and 

exodermic grid decks), and steel railings. Other less common 

applications include steel pier columns, pier bents and cellular 

sheet piling abutments.

One advantage that steel has over precast concrete is that it 

typically weighs less than an equivalent concrete element. This 

factor can be critical when considering shipping, crane capacities, 

and SPMT capacities. 

Steel has the ability to handle large stress reversals. SPMT 

bridge moves typically induce large stress reversals during lifting 

and transport. Pretensioned prestressed concrete beams have 

limited capacity for these stress events.

5.1.2. Concrete (Normal Weight and Lightweight)

Concrete is a popular and versatile material for prefabrication and 

ABC projects. The ability to build elements off site in virtually any 

shape makes this material a prime choice for designers. Common 

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prefabricated concrete elements include beams and girders, full 

depth deck panels, and pier caps. Several states have built entire 

bridges using precast concrete elements including pier columns, 

abutment stems, footings, and retaining walls.

Concrete can also be used for making connections between 

different prefabricated bridge elements. These connections often 

require the use of high early strength concrete to allow for 

accelerated construction processes. 

Durability is a major concern of bridge owners. The new 

generation of high performance concretes offer durability that 

exceeds the performance of past concretes. Plant produced 

precast concrete also has the advantage of being constructed in a 

controlled environment with higher production and curing 

standards than normally found in the field. This benefit of higher 

quality materials of accelerated construction projects is often 

overlooked or undervalued by designers.

One obstacle to the use of prefabricated concrete elements is the 

shipping and handling weight. One way to reduce the weight of 

the elements is to cast voids in the elements during prefabrication. 

Once in place, the voids can be filled with concrete. The voids 

can also be used to make connections between elements. A 

common cost effective way to make voids is to use corrugated 

steel pipe to form the void. The corrugations are very effective at 

transmitting very large forces. There have been several research 

projects that have been completed where the use of corrugated 

steel voids was studied. Two studies of note are Development of 

Precast Bent Cap Systems for Seismic Regions [11] (NCHRP 

Report 681), and Precast Concrete Elements for Accelerated 

Bridge Construction [12].

Figure 5.1.2-1 is a sketch of a cantilever abutment showing 

corrugated steel pipes used to reduce the weight of the abutment 

stem elements and also to make a connection to a precast 

concrete abutment cap. The cap connection is made with 

reinforcing steel dowels cast into the void. The reinforcing is not 

shown for clarity.

Figure 5.1.2-2 is a sketch of an integral abutment showing 

corrugated steel pipes used to reduce the weight of the stem 

elements and also to make a connection to the piling. This 

approach is based on research completed at Iowa State University 

[12].

Another way to reduce the weight of elements is through the use 

of lightweight concrete. The unit weight of concrete can be 

reduced by 20 percent or more. Lightweight concrete can have a 

substantial impact on the equipment needed for installation of 

prefabricated elements. In some cases, the cost savings on the 

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equipment has been found to out-weight the premium that is paid 

for the lightweight concrete. The reduced unit weight also reduces 

the internal forces and stresses on elements as they are handled. 

The Utah DOT has used lightweight concrete bridge decks on 

several bridges installed using SPMTs. Appendix C contains a 

sample specification from the Utah DOT for lightweight concrete. 

One down-side to lightweight concrete is that some states require 

overlays on lightweight concrete decks. This requirement can add 

to the overall project cost and timeframe.

Figure 5.1.2-1 Transparent View of a Cantilever Abutment 

Showing Corrugated Pipe Voids 

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Figure 5.1.2-2 Transparent View of an Integral Abutment

Showing Corrugated Pipe Voids 

Concrete is not only used for fabrication of elements, it can be 

used for connections between elements. There are many ways to 

connect bridge elements using grouts and mechanical connectors; 

however it is inevitable that small closure pours will be required to 

complete some connections. Figure 5.1.2-3 shows a detail from 

the Utah DOT ABC standard details. It depicts the integral 

abutment connection to the bridge superstructure. Concrete is 

used to connect the drilled shaft to the abutment cap (via a 

corrugated pipe void) and to connect the superstructure to the 

substructure. This latter pour connects the beams, deck, 

backwall, abutment stem, and approach slab, all with one pour. 

Construction tolerances in all of these elements would not allow 

for a tight fit-up of all of these elements. The concrete closure 

pour can make up for all of the tolerances in one location. This is 

an example of an efficient use of cast-in-place concrete in ABC 

construction.

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Concrete link-slab technology has also been used on ABC 

projects at bridge piers to make a jointless bridge without live load 

continuity. The concept with link slabs is to design the connection 

of the deck across the pier to accommodate the rotation of the 

beams without significant cracking. This is done by de-bonding a 

small portion of the deck near the pier to allow for a wider spread 

of the rotation strain. Information on link slabs can found in the 

following papers:

• Behavior and Design of Link Slabs

Decks [13]

• Combining Link Slab, Deck Sliding

Revising Bearings [14]

Figure 5.1.2-3 Sample Cast-in-place Closure Pour Detail 

(source: Utah DOT)

 for Jointless Bridge 

 over Backwall, and 

5.1.3. Timber

Timber bridges were common in the 1800’s; however the use of 

timber has waned in the last 75 years. There has been a 

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resurgence in the use of timber as a bridge material during the last 

two decades. The use of glue laminated products make the 

design of larger timber bridge elements more practical and cost 

effective. Common types of prefabricated timber bridge elements 

include glue laminated deck panels and glue laminated beams 

and stringers.

5.1.4. Aluminum

Aluminum elements have been used in the past in various bridge 

projects. The Pennsylvania DOT has built aluminum girder 

bridges and used aluminum for bridge decks. Aluminum can be 

used for prefabricated bridge girders and bridge decks. The 

material can be extruded into panels that can be connected in the 

field. Connections can then be made to the bridge girders via 

grout pockets. 

5.1.5. Fiber-Reinforced Polymer

There has been much research into the use of fiber-reinforced 

polymers in recent years. Many states and universities have 

experimented with these materials. The development of high 

strength polymers has made the use of FRP materials practical for 

many bridge applications. Types of FRP bridge elements include 

beams and stringers and full-depth deck panels. 

The state of New York has had FPR deck systems in place for 

almost a decade with excellent performance. Maine has led 

research on the use of fiber exoskeleton structures, pioneering 

both a technology called “Bridge in a Backpack” and a beam 

product with a concrete arch encased in a fiber- reinforced case 

designed by John Hillman. 

5.1.6. Grouts

Many of the precast concrete elements discussed in this Manual 

are joined with grout. The connections between precast concrete 

elements require the use of grout to fill the void between the 

adjoining elements. Nominal width joints are required for several 

reasons. The primary reasons are to allow for element tolerances 

and to make adjustments in the field. See Section 7.4.3 for more 

information on element tolerances.

Non-shrink cementitious grout is most often used to easily and 

efficiently provide a durable, structurally stable connection 

between precast concrete elements. Epoxy grouts can be used; 

however, they tend to have a low modulus of elasticity and are 

expensive when compared to cementitious grouts. In order to 

achieve desired results, careful selection and specification is 

required when using non-shrink grouts.

The following section contains information on different grout types. 

The FHWA manual entitled Connection Details for Prefabricated 

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Bridge Elements and Systems [3] has more information on grout 

placement, curing and specifications.

5.1.6.1. Grout Types

There is no such thing as a generic non-shrink grout. 

There are several different types of grouts, each with its 

own advantages and disadvantages. Cementitious nonshrink grouts are inexpensive, generally easy to work with, 

and develop adequate strengths in reasonable time. 

These grouts are often pre-packaged and can be extended 

using small diameter stone for larger pours. Cementitious 

grouts are ideal for static and light dynamic loadings. This 

section will focus on cementitious non-shrink grouts since 

they are adequate for virtually all prefabricated 

connections. Other grout types may be acceptable for 

precast connections but require additional specification 

and suitability considerations on the part of the designer. 

Ideally a non-shrink cementitious grout will not exhibit 

dimensional change in the plastic or hardened state. To 

achieve non-shrink characteristics in grout, additives are 

mixed into the grout to counteract the natural tendency of 

grouts to shrink. There are different types of additives for 

cementitious grouts in the market. The additives have 

certain advantages and disadvantages. Several common 

additives are as follows:

Gas Generating:

This is the most common grout type. A chemical 

substance is added to the grout mixture to control 

shrinkage. In most cases, an aluminum powder is used. A 

chemical reaction occurs with the aluminum powder and 

the alkalis in the cement during the plastic phase to form 

hydrogen gas. The generated gas is used to promote 

expansion. 

However, because small amounts of aluminum powder are 

used, the expansion can be difficult to control under 

various conditions. This uncontrolled expansion can cause 

bleed water to form at the grout surface that can cause 

loss of support and bond. This has led to the development 

of alternative compounds that can ensure a quality grout 

under varying conditions.

Ettringite: 

Ettringite expansive grout relies on the growth of ettringite 

crystals during the hardened state to counteract shrinkage.

Air Release:

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Air release grouts do not rely on a chemical reaction to 

achieve expansion. The additive reacts with water to 

release air and cause expansion.

5.1.7. Ultra High Performance Concrete

A new generation of high performance concrete has emerged in 

the ABC market. The material is referred to as Ultra High 

Performance Concrete (UHPC) or as Reactive Powder Concrete. 

This proprietary product combines high quality cement and stone 

products along with either steel or organic fibers. The material 

can achieve very high compressive strengths of 18,000 to 33,000 

psi. Another key feature of the material is that it can also achieve 

very high flexural strengths of between 900 and 7000 psi 

depending on the type of fibers used. This leads to a material that 

is very ductile. 

Recent research into the product has shown that under high 

tensile loading, the UHPC will develop tension cracks; however 

the cracks are very small and tightly spaced, as opposed to wide 

intermittent cracks found in normal reinforced concrete elements 

that are exposed to high tensile stresses. UHPC also has very 

low permeability, which should lead to long service life. FHWA 

research has shown promising results for several applications 

(adjacent beam elements, precast full depth deck panel 

connections). The work focused on creep, shrinkage, resistance 

to chloride ion penetration, and freeze-thaw behavior.

This high performance material comes at a cost. The unit price for 

the material is much higher than conventional high performance 

concrete; therefore replacement of high performance concrete 

with UHPC on major bridge elements is not financially viable at 

this time. UHPC has been successfully used on several bridges in 

the United States for girders and decks on an experimental basis.

Even with its high cost, UHPC has a high potential for use in ABC. 

The high compressive and tensile strength makes the product 

ideal for closure pour connections between adjacent elements. 

On-going testing at FHWA has shown that UHPC can develop 

reinforcing bars in very small distances. This opens up the 

potential to have very small closure pours that are fully reinforced. 

This is perhaps the best use UHPC at this time, where designers 

can take advantage of the extremely high strength without 

incurring high overall costs for the bridge. This approach is being 

studied under the SHRP2 Project R04 entitled “Innovative Bridge 

Designs for Rapid Renewal”. More information on this subject will 

be available once this research is completed.

Figure 5.1.7-1 is a sketch of a potential flange connection for a 

double tee girder in use in the Northeast United States called the 

NEXT Beam. The goal of this connection is to achieve a full 

moment connection with a lap splice of approximately 5”. UHPC 

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is being investigated for the closure pour connection. The benefit 

of this typs of connection is that it will provide enough moment 

capacity to make the beams act as a unit. This will allow the use 

of a live load distribution factor for bridge cross section Type “e” in 

Table 4.6.2.2.1-1 of the AASHTO LRFD Bridge Design

Specifications [8].

Figure 5.1.7-1 Potential UHPC Connection for the NEXT Beam

(Northeast Extreme Tee) 

5.1.8. Corrosion Resistant Reinforcing Steel

The use of corrosion resistant reinforcing steel is becoming more 

prevalent in the United States. Corrosion resistant reinforcing 

offers several advantages over epoxy coated reinforcing bars 

when used in ABC applications. The lack of coatings on the bars 

allows designer to layout closure pour areas with shorter lap splice 

lengths. The strengths of these materials are also higher than 

conventional reinforcing steel; therefore the number of bars in a 

connections could potentially be reduced. Epoxy coated bars are 

in use in many states. These bars are less expensive than other 

corrosion resistant bar options.

5.1.8.1. Stainless Steel

Stainless steel has long been known as a highly corrosion 

resistant material. It is a staple of the medical and food 

service industries because of it high resistance to 

corrosion. Stainless steel reinforcing bars have been in 

the United States Bridge Market for many years; however 

widespread use has not been seen. Recently, several 

states started specifying stainless steel in order to improve 

the service life of key elements in the bridge structure, 

such as the decks.

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Specifications for stainless steel reinforcing bars can be 

found in ASTM A955-10a Standard Specification for 

Deformed and Plain Stainless-Steel Bars for Concrete 

Reinforcement [15].

5.1.8.2. Low-carbon, Chromium, Steel Bars

A corrosion resistant alloy of steel has been developed for 

use in reinforcing steel. This material is up to five times 

more corrosion resistant than conventional reinforcing. It 

also provides higher strength. The corrosion resistance is 

not a high as stainless steel; however the unit cost of the 

material is less, which makes this an attractive alternative 

to conventional coated reinforcing.

More information on the use of this material can be found 

in NCHRP Report 679 entitled “Design of Concrete 

Structures using High-Strength Steel Reinforcement [60]. 

Specifications for low carbon, chromium steel reinforcing 

bars can be found in ASTM A1035 - 09 Standard 

Specification for Deformed and Plain, Low-carbon, 

Chromium, Steel Bars for Concrete Reinforcement [16] 

and AASHTO MP 18M/MP 18-09 Uncoated, CorrosionResistant, Deformed and Plain Alloy, Billet-Steel Bars for 

Concrete Reinforcement and Dowels [59].

5.1.8.3. Coated and Galvanized Bars

Coated reinforcing bars have been used for many years. 

There are two common coatings. The first is epoxy 

coatings. The epoxy prevents moisture from contacting 

the bar and thereby breaks a potential corrosion cell. 

Epoxy coatings are typically the most cost effective 

corrosion resistance option. One down side to epoxy 

coatings have reduced bond with the concrete; therefore 

they require longer lap splice lengths. This can become an 

issue with the size of closure pour joints.

Another coating option is hot dipped galvanizing. This 

coating is the application of zinc by means of dipping the 

bars in a molten zinc bath. The zinc coating becomes 

integral with the bat as opposed to a coating that can chip 

off. Galvanizing differs from epoxy coatings in that it dies 

not simply prevent moisture from contacting the bar. The 

zinc is a sacrificial material that will form a corrosion cell 

before the corrosion cell can form in the steel bar. 

Galvanized bars do not have the same issues with bond as 

with epoxy coated bars.

5.1.8.4. Fiber Reinforced Polymer (FRP) Bars

There are several types of fiber reinforced polymer 

reinforcing bars in use. The most common are glass fiber 

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bars and carbon fiber bars. These bars do not require 

coatings since the base material is non-corrosive. The 

most popular use of FRP bars has been in bridge decks. 

This is due to the high exposure of the decks to corrosive 

environments. FRP bars are typically more expensive than 

steel bars; however, they can be a reasonable choice 

when life cycle costs are considered. Bending of FRP bars 

is not possible, therefore geometries for bend bars needs 

to be carefully planned during the fabrication process. 

5.2. Superstructure Elements

Superstructures are defined by AASHTO as “Structural parts of the bridge 

that provide the horizontal span.” For conventional bridges, the 

superstructure is often defined as the portion of the bridge above the 

bridge bearings. The following sections contain information on typical 

superstructure elements and systems used for ABC. These systems 

include decks, stringers/beams, and large modular systems.

5.2.1. Beams and Girders

Prefabrication of beams and girders has been an integral part of 

bridge construction in the United States for many years. For this 

reason, this subject will not be covered in any great detail in this 

manual. The application of these systems to ABC will be 

presented here instead.

5.2.1.1. Steel

Welded steel girders can be configured in many ways to 

form a superstructure framing system. The development 

of high performance weathering steels (HPS) has the 

potential to reduce the need for painting and/or long-term 

maintenance over the service life of the bridge. HPS 

steels have higher strengths and better corrosion 

resistance than previous typical weathering steels. They 

also provide improved weldability and higher fracture 

toughness. 

Steel beams can be combined with a pre-topped concrete 

deck to form modular superstructure units. These modular 

units have been used to allow the replacement of 

superstructures in hours instead of months.

5.2.1.2. Precast/Prestressed Concrete

Precast prestressed concrete is one of the most common 

forms of prefabricated superstructure girders. High 

performance concrete (HPC) has been introduced into the 

market to improve the performance and durability of 

concrete girders. The use of more efficient shapes such 

as bulb tee girders has become more common. 

Adjacent butted precast girder systems such as double 

tees and deck bulb tees create opportunities for ABC. 

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These girders function as both the beam and the deck, 

thereby eliminating the need for deck placement in the 

field.

5.2.2. Stay-in-place Deck Forming 

Stay-in-place deck forming can be used to reduce construction 

time by eliminating the need to strip forms after deck casting. 

Several systems have been in use in the United States for many 

years.

5.2.2.1. Corrugated Steel

Galvanized corrugated steel deck forms can be used to 

support the deck reinforcing and the cast concrete. These 

forms span from flange tip to flange tip on adjacent girders. 

The forms are intended to remain in place for the life of the 

structure. 

They can be used on both steel and concrete girders. 

Grade adjustment and forming of the beam haunch is 

normally accomplished through the use of light gage steel 

angles placed at the flange edges.

Light gage steel stay-in-place forms are widely used in the 

building industry. In some applications, the forms are used 

as the tension reinforcing for the deck. This approach has 

not been used in the bridge industry due to the high 

moment demand in bridge decks.

The corrugations may require an increase in the volume of 

concrete so that the lower corrugations can be filled. This 

can result in an increase in the overall dead load of the 

bridge. Some states have used expanded polystyrene 

foam in the corrugations to mitigate this issue. Other 

designers take advantage of the location of the 

corrugations to place bottom transverse bars within the 

lower corrugations, which reduces the overall concrete 

mass to the same as a conventional formed deck. This 

approach can only be used where the reinforcement is 

parallel to the corrugations.

5.2.2.2. Partial-depth Precast Concrete Deck Panels

Partial-depth precast concrete deck panels are similar to 

steel stay-in-place deck form in that they remain in place 

and support cast concrete. The difference is that the panel 

makes up the bottom portion of the structural deck. 

Partial-depth precast concrete deck panels have been 

used by many states, and are extensively used in some 

states. For example, 85 percent of all bridges built in 

Texas use this forming method [17]. These panels are 

typically 3.5 to 4 inches thick and placed on top of the 

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beams on interior bays. The typical details used in Texas 

can be found at the Texas DOT Website: www.state.tx.us. 

Overhangs on bridges with these panels are usually 

formed using conventional forming methods. The panels 

have not been cantilevered over the fascia beam because 

normally the design requires a composite connection 

between the beam and the deck. A continuous deck panel 

interferes with this connection. In the past the Texas DOT 

experimented with a system that used blockouts for shear 

connectors, but has since decided that it is easier to simply 

form the overhangs using conventional deck forming 

techniques.

Once placed, a top layer of conventional reinforcing is 

placed over the panels and a partial-depth concrete pour is 

made to finish the composite deck.

These deck panels serve two purposes:

1. They act as a form to support the wet concrete of 

the deck pour. The slowest portion of reinforced 

concrete deck construction is the installation of 

deck formwork. On a conventional bridge, this is 

accomplished using wood forms or steel stay-inplace forms. These forms need to be fitted 

between the beam flanges within tight tolerances. 

The precast concrete panels span between the 

beams and overlap the beam edges. They are 

supported temporarily on bedding strips on top of 

the flanges until the deck concrete flows 

underneath them to provide continuous support; 

therefore, installation is faster and requires less 

manufacturing tolerance.

2. The deck panels also act as the lower portion of the 

reinforced concrete deck. This is possible 

because the moment demand in a deck is primarily 

positive bending in the middle portion of the bay 

between beams, and negative bending over the 

beams. Having a discontinuity of bottom mat 

reinforcing over the beams between the panels is 

not an issue because the moment demand is 

resisted by the top reinforcing in the cast-in-place 

top pour.

 

Significant research has been completed on partial-depth 

deck panels. The Texas DOT has sponsored much of this 

research [18]. There have been laboratory studies and 

field verification test. Strength tests and cyclic live load 

tests have also been completed. The results of this 

research show the following:

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• Decks composed of precast panels topped with 

cast-in-place concrete are stronger and stiffer than 

full-depth cast-in-place concrete decks [19].

• The panels can be considered a part of the 

structural deck system.

• Composite action between the panels and the 

topping concrete is possible without the use of 

horizontal shear reinforcement.

• The panels combined with the concrete topping can 

be used as a composite deck for the design of the 

beam.

• It is preferred to use prestressing as the main 

reinforcement in the panels.

• The amount of force and the size of the prestress 

strand should be kept as low as possible to 

minimize cracking and the development 

requirements of the strand.

Texas and Tennessee have had good performance on 

their decks where partial-depth precast concrete decks 

panels have been used. The key to good performance is a 

positive support between the panels and the top of the 

girders. Other States have experienced problems with the 

panels where fiber board was used to support the panels. 

The board deteriorated over time and there wasn’t a 

positive support between the panels and the girders. 

Research has shown that there is a need to work the 

concrete under the edge of the panels to achieve this 

positive support

Flexibility of the superstructures should also be taken into 

consideration. Virginia has experienced significant 

reflective cracks on flexible steel structures with span 

lengths greater than 140 feet. These reflective cracks can 

affect the long-term durability of the deck, particularly 

where deicing chemicals are used.

5.2.3. Full-Depth Deck Panels

The most common form of ABC in use in the United States is the 

use of full-depth deck systems. The process of installing a bridge 

deck is one of the most labor intensive operations in bridge 

construction. Prefabrication of deck systems offers an opportunity 

to significantly reduce construction time. The following sections 

describe the most common forms of prefabricated decks systems 

in use.

5.2.3.1. Precast/Prestressed Concrete

Full-depth precast concrete deck systems have been used 

by a number of states. A group of northeast states, 

working as a PCI Bridge Technical committee, has 

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published design and detailing standards for this type of 

system [20]. The Utah DOT has also published standard 

details for full depth precast deck panels. In general, this 

system is designed as a one-way slab between supporting 

beams using either mild reinforcement or prestressing. 

Figure 5.2.3.1-1 shows a precast deck panel installation on 

a bridge in Iowa. The photo shows the use of longitudinal 

post tensioning system used to interconnect the panels 

and the blockouts used to connect the panels to the 

beams. Figure 5.2.3.1-2 shows panel leveling devices that 

were used on the same project. The leveling devices allow 

the adjustment of the deck panels to meet the prescribed 

grade. They also provide proper dead load distribution to 

the supporting beams. This is done by tightening all of the 

leveling devices to the same torque. This project was a 

FHWA Highways for LIFE demonstration project. More 

information on this project can be obtained at the FHWA 

Highways for Life website: 

www.fhwa.dot.gov/hfl/summary/projects_summary.cfm. 

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Figure 5.2.3.1-1 Precast Full Depth Deck Installation

Figure 5.2.3.1-2 Precast Full Depth Deck Leveling System

There has been significant research [21-37] involving the 

use of full-depth precast concrete deck panels; therefore, 

many of the details are thoroughly tested and the behavior 

of the systems is well known. Most research has focused 

on the connection between the deck and the supporting 

beams. Composite action is a prerequisite for most 

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designs; therefore, this connection is critical. Most of this 

research has been completed on steel beam connections, 

and several studies have been completed on precast 

concrete beams. More research is underway on the 

connection of deck slabs to concrete beams; therefore 

designers should keep apprised of further work in this 

area. 

The AASHTO LRFD Bridge Specifications includes some 

requirements for the design of precast concrete deck slabs 

on girders (LRFD Section 9.7.5 [8]). This includes the 

need for transverse grouted shear keys combined with 

post-tensioning (on longitudinal girder bridges). Recent 

research has shown that a connection without posttensioning is viable [9]. Other researchers are studying 

connections using Ultra High Performance Concrete. 

These studies may lead to modifications to the AASHTO 

provisions in the future.

Research is underway at Iowa State University for a new 

deck panel system that takes advantage of the high 

strength and quality of ultra high performance concrete. 

This work is being funded through a grant from the FHWA 

Highways for LIFE Technology Partnerships Program. The 

panels resemble a waffle on the bottom with longitudinal 

and transverse ribs containing the reinforcing bars. The 

top surface is smooth. This system promises to be 

lightweight and very durable. The research includes girder 

connections and fatigue testing. A trial bridge in Iowa will 

be built with the new system.

More information on precast deck panels can be found in 

the FHWA Manual entitled “Connection Details for 

Prefabricated Bridge Elements and Systems” [3].

5.2.3.2. Steel Grid

There are several steel grid deck systems in use in the 

United States. In most cases, the steel grid provides the 

structure system for the deck. Some systems combine the 

grid with composite concrete to form a solid deck system 

with a smooth riding surface. All of these systems can be 

prefabricated for rapid installation.

One advantage to these systems is that they typically are 

lighter in weight when compared to concrete decks. This 

helps to reduce shipping and handling costs for the 

elements. Grid panels can also be used to increase the 

load capacity of older bridges that require deck 

replacements.

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The AASHTO LRFD Bridge Design Specifications include 

provisions for the design of metal grid decks [8]. 

Designers are also encouraged to contact the Bridge Grid 

Flooring Manufacturers Association for assistance with 

details of grid decks (www.bgfma.org).

The following sections describe the most common forms of 

prefabricated grid decks systems in use. More information 

on grid decks can also be found in the FHWA Manual 

entitled “Connection Details for Prefabricated Bridge 

Elements and Systems” [3].

Open Grid

Open grid decks have been used for many years. 

They are most common on bridges that require very 

lightweight decks, such as moveable bridges and 

suspension bridges. However, long term durability of 

elements below the open grid decks are a concern and 

should be addressed accordingly. This is due to the 

exposure of the framing to the elements, including road 

salts in northern climates.

Grid decks are essentially mini-steel framing systems. 

They usually consist of main rail members in one

direction that span between supporting beams, and 

transverse cross bars in the perpendicular direction 

that run parallel to the supporting beams. 

Concrete Filled Grid

These systems consist of decks that include a 

combination of concrete and steel elements. The most 

common systems involve the use of steel grid. There 

are two common options for these systems, as 

described below:

Partially Filled Grid Decks

These systems include a steel grid deck in which the 

upper portion of the deck is filled with concrete. In 

most cases, the concrete is filled over the top of the 

grid to improve performance by covering the top of the 

grid.

Exodermic DecksTM

An exodermic deck is a proprietary deck system that is 

similar to partially filled grid decks except the concrete 

is primarily placed above the grid. The main bars act 

as mini-composite steel beams in concert with the 

concrete over pour. These decks are lightweight and 

lend themselves to prefabricated operations. Figure 

5.2.3.2.2-1 shows exodermic deck details and Figure 

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5.2.3.2.2-2 is a photograph of a prefabricated 

exodermic deck installation during a nighttime closure.

Figure 5.2.3.2.2-1 Exodermic Deck Details

(source: D.S. Brown Company) 

Figure 5.2.3.2.2-2 Exodermic Deck Installation

(source: D.S. Brown Company) 

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Another similar deck system is the EffideckTM system 

developed by the Fort Miller Company in New York. 

This is a composite concrete and steel tube deck 

system. This deck system is a composite system that 

includes both steel members and precast concrete. 

The use of steel ribs reduces the overall weight of the 

deck. Figure 5.2.3.2.2-3 shows the underside of the

EffideckTM system. 

Figure 5.2.3.2.2-3 Underside of the EffideckTM system

(source: The Fort Miller Company) 

 

Users of the Manual are encouraged to contact the 

manufacturers of these systems for guidance with 

connections for specific bridge projects.

Metal Panel Decks

Metal panel decks have been in use for many years. Metal 

deck systems can provide very long service life with 

reduced weight when compared to traditional concrete 

decks. The following sections include information on the 

most common metal deck systems. 

Orthotropic Steel Decks

An orthotropic deck system is comprised of a steel top 

plate that is supported by open or closed ribs that are 

welded to the underside of the top deck plate. This forms 

a system that is very durable and lightweight. Orthotropic 

decks are primarily used in long span bridges and 

moveable bridges where savings in deck weight have a 

significant impact on the overall design of the bridge. 

Figure 5.2.3.2.3-1 is a sketch of an orthotropic bridge deck 

panel.

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There have been issues with fatigue cracking in the welds 

in the systems used to date. Significant research has been 

undertaken to address these issues and improve the 

design methodologies. Designers are encouraged to study 

past research before undertaking a design of an 

orthotropic deck. The cost for orthotropic decks has 

traditionally been higher than concrete bridge decks. This 

is often offset by the extended service life that these 

systems can provide. 

FHWA is currently investigating ways to reduce costs for 

orthotropic decks through the use of modular designs and 

automated shop welding technologies.

Extruded Aluminum Decks

Over the years, various forms of aluminum deck systems 

have been used on bridges. Aluminum is a material that 

lends itself to extrusion processes. Using this technology, 

complex shapes can be fabricated including internal closed 

rib systems. Aluminum also offers a significant savings in 

dead load, which makes it attractive for rehabilitation of 

bridges with load restrictions. 

Aluminum bridge decks are desirable because of the high 

strength to weight ratio of the material. The weight savings 

can reduce shipping and handling costs and reduce the 

cost of the supporting members. It can also be used for 

the replacement of decks on existing load restricted 

bridges. Concerns over weldability of aluminum and the 

unit cost of aluminum has restricted the use of the material 

in the past; however there are new manufacturing 

technologies that have been developed that are improving 

the quality and reducing the fabrication and construction 

costs. Figure 5.2.3.2.3-1 shows a portion of an aluminum 

bridge deck extrusion.

Figure 5.2.3.3-1 Orthotropic Bridge Deck

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Steel Sandwich Panels

New technologies have been brought into use to produce a 

steel sandwich panel system. This system is similar to the 

orthotropic deck system except it has a bottom plate in 

addition to the top deck plate, which forms a sandwich. 

The final product is similar to the aluminum deck panel 

system previously discussed.

The fabrication of a steel sandwich panel requires special 

welding techniques. Welding of ribs in an orthotropic panel 

system is accomplished in the inverted position with all 

welds on the underside of the top deck plate. A sandwich 

panel can only be built half-way in this manner. The top 

deck plate can be joined to the internal ribs in the inverted 

position; however, the connection of the bottom plate to 

the ribs cannot be welded using traditional welding 

equipment. Hybrid Laser Arc Welding (HLAW) technology 

is used to solve this problem. This technique can weld two 

thin plates (less than 1⁄4”) together that are laid on top of 

one another. The welding can be made through one plate 

and into the lower plate. This allows the bottom plate to be 

attached to the internal rib plates from the outside.

Laboratory research has been completed by the Maine 

Department of Transportation on steel sandwich panels 

that included a study of welding techniques and an 

analysis of the panels using finite elements [39]. Maine 

DOT is planning on installing a steel sandwich panel 

system on a local bridge. Figure 5.2.3.2.3-2 is a sketch of 

the panel that was studied in the research.

Figure 5.2.3.3-2 Aluminum Deck Extrusion

(source: SAPA Industrial Extrusions) 

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Figure 5.2.3.3-3 Trial Steel Sandwich Panel Bridge Deck

Prefabricated Timber

The United States Department of Agriculture Forest 

Products Laboratory (USDA FPL) has developed standard 

details for timber bridges, including details for prefabricated 

timber panels and beams. There is a significant amount of 

information on timber bridges at the USDA FPL website. 

At this time, most timber bridges are used on low volume 

roadways, but may be applicable to higher volume roads 

as well. The performance of timber bridges has been very 

good, especially in regions where the environment is dry. 

Users of this Manual are encouraged to visit the Forest 

Products Laboratory website for more information on 

timber bridges (www.fpl.fs.fed.us).

Prefabricated timber beams and panels are normally 

manufactured using the glue laminating process. This 

involves gluing nominal dimension lumber side-by-side to 

create a solid panel. For deck panels, the wide dimension 

of the laminations is typically placed vertical. Protection 

against rotting is controlled by the use of pressure treated 

wood products. The individual laminations can be 

pressure treated before being laminated together, or the 

laminated pieces can be pressure treated after fabrication. 

The glue used for bridge application must be water proof.

Timber deck panels have been used in two ways: 

• Installed on top of beams (glue laminated wood

beams or steel beams) 

• Installed as adjacent-deck-slab superstructure for 

short span bridges

The deck panels can be connected with bolting or with 

post-tensioning. The post-tensioned system offers 

improved durability; however the tensioning process must 

be repeated several times during the construction process 

due to creep of the wood fibers, which tends to relax the 

post-tensioning forces.

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5.2.3.3. Fiber Reinforced Polymer

Fiber reinforced polymers have been used in the 

aerospace industry for years but have been used only 

recently in the bridge industry. FRP composites can be 

manufactured with several different types of fibers 

combined with polymer resins to form structural shapes. 

The choice of fiber affects the material properties of the 

finished product. The most common fibers used are glass 

fiber and carbon fiber. FRP can be molded into virtually 

any shape by using established manufacturing methods 

such as pultrusion and vacuum assisted resin transfer.

FRP products offer the following advantages over other 

structural materials:

• High tensile strength

• Lightweight

• High fatigue resistance

• Corrosion resistance

The lightweight properties have led to the use of FRP 

decks on bridge rehabilitation projects. The use of FRP 

deck panels can have a significant positive effect on the 

load capacity of the bridge. FRP can be molded into 

cellular panels that can be used as full-depth deck panels. 

The panels are similar to the aluminum and steel sandwich 

panel decks described above. FRP products to date have 

not been standardized. Each project has been “one of a 

kind,” based on the manufacturing process of the supplier. 

Virginia has installed three FRP decks. West Virginia, 

Pennsylvania, and Delaware have also installed FRP 

decks. Ohio had an initiative to install an FRP deck in 

each of its counties.

5.2.4. Modular Superstructure Systems

Modular superstructure systems are gaining popularity in the ABC 

market. Accelerated construction can be achieved because the 

pre-topped modules do not require the installation of a deck after 

erection. It offers benefits over prefabricated deck systems since 

the deck is connected to the beam or girder during fabrication. 

This significant connection which normally calls for grouted shear 

connector pockets can be a time consuming process in the field, 

even on ABC projects.

Construction of modular beam systems can be accomplished in 

less than two days. Some states have installed modular units 

using an overnight construction timeframe. The connection of the 

deck edges is the key to long term durability. The following three 

systems are most commonly found in use today: 

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• Closure pour with lapped reinforcement

• Small closure pour with Ultra High Performance Concrete 

(see Section 5.1.7)

• Small closure pour with headed reinforcing bars and nonshrink grout

• Grouted shear key with transverse post-tensioning

• Match cast epoxied edges with transverse post-tensioning 

It is very important to use non-shrink or low shrinkage materials in 

closure pours. Shrinkage of the closure pour concrete can result 

in transverse cracking or cracking along the precast interface. 

This cracking is caused by the restraint brought on by the adjacent 

modular units. Several states are using shrinkage modifying 

admixtures to reduce the amount of drying shrinkage in the 

closure pour concrete. Section 7.8 contains more information on 

concretes used for closure pours.

The use of modular systems inevitably leads to the need to move 

and erect larger and heavier elements. There are limitations to 

the use of modular systems that can be controlled by dimensional 

and weight shipping restrictions and maximum crane capacities. 

Modules with spans over 100 feet have been used with weights of 

approximately 150,000 pounds. Lightweight concrete can be 

considered to offset the weight of larger modules. 

The design team will need to evaluate the feasibility of shipping 

and erecting large modular systems. A detailed erection 

procedure should be investigated in order to determine the 

feasibility of the proposed system.

In special cases, a fabrication area near the bridge may offer the 

best opportunity. This will allow for the fabrication of larger 

modules that can be moved with specialized equipment. Chapter 

2 includes several examples of specialized equipment that can be 

used to move larger modules. These include SPMT gantries and 

larger cranes.

5.2.4.1. Modular Steel Systems

Topped Multi-beam Units 

Steel modules offer advantages over precast double tee 

systems and deck bulb tee systems in some instances due 

to the reduced shipping weight of the modules. Several 

projects have been completed to date that involved 

modular elements that have two or three steel beams that 

are topped with a precast reinforced concrete deck. Figure 

5.2.4.1-1 is a sketch of a modular steel bridge concept that 

was developed by the Massachusetts DOT.

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These modules can be transported and erected in a matter 

of hours. The bridges can be opened to traffic once the 

connections at the deck edges are completed. This 

approach is also being studied under the SHRP2 Project 

R04 entitled “Innovative Bridge Designs for Rapid 

Renewal”. More information on this subject will be 

available once this research is completed.

A modular steel folded plate girder system has also been 

developed by the University of Nebraska. This consists of 

modular steel inverted tub girder elements topped with a 

precast concrete deck. The beams are made of a single 

folded steel plate. Figure 5.2.4.1-2 shows the folded plate 

bridge being tested at the University of Nebraska. This 

system could be very useful for short span bridges. 

Currently the system is limited to spans under 60 feet due 

to limits on plate bending equipment.

Figure 5.2.4.1-1 Modular Steel Topped Multi-beam Units 

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Figure 5.2.4.1-2 Folded Plate Modular Bridge Element

(source: National Steel Bridge Alliance) 

Design: Simple Span for DL, Continuous for LL

Multi-span structures can be achieved by using the 

technology of designing the beams as simply supported for 

dead load and continuous for live load. This approach has 

been used for many years in the prestressed concrete 

industry. By using this technique for modular steel beam

units, the time consuming process of in-span bolted field 

splices can be reduced or eliminated. If live load continuity 

is not required, link slab techniques can be used to provide 

a jointless deck at the piers. 

The University of Nebraska has studied a cast-in-place 

closure pour connection for continuity at the piers [40]. 

They have studied steel I-girders and box girders. The 

conclusion was that full live load continuity can be 

achieved using simple connection details.

Orthotropic Systems

Another potential use of steel in ABC is through the use of 

modular orthotropic steel deck systems. The two systems

being investigated are a single span orthotropic 

superstructure with the ribs running the entire span of the 

bridge, and an orthotropic deck T beam that combines a 

steel girder with a portion of an orthotropic deck. Figures 

5.2.4.1-3 and 4 show the two systems being investigated.

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Figure 5.2.4.1-3 Modular Orthotropic Deck Span 

Figure 5.2.4.1-4 Modular Orthotropic T-Beam Bridge Details

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As with orthotropic deck systems, the cost for fabrication 

can be detrimental to widespread use of these systems. 

FHWA is investigating ways to reduce costs by 

standardizing designs and through the use of innovative 

automated fabrication techniques. 

5.2.4.2. Modular Precast Concrete Superstructure Systems

Precast and prestressed concrete elements offer 

significant opportunities for modular superstructure 

systems. Any system that incorporates the bridge deck 

into the beam elements will normally result in an 

accelerated construction process. As with modular steel 

elements, the connections between the adjacent modules 

are critical to durable long-term performance (see Section 

5.2.4). This approach is also being studied under the 

SHRP2 Project R04 entitled “Innovative Bridge Designs for 

Rapid Renewal”. More information on this subject will be 

available once this research is completed.

Double Tees

Adjacent butted precast concrete sections have been in 

used for many years. These structures eliminate the need 

to form and cast a concrete deck in the field. Traditionally, 

adjacent butted beam bridges consisted of precast 

concrete adjacent box beams or deck slabs that were 

connected with shear keys, bolts or transverse posttensioning. New approaches to butted systems are 

evolving through the use of new decked precast sections 

such as deck bulb tee girders and decked double tee 

sections. Figure 5.2.4.2-1 is a sketch of a cross section of 

an adjacent precast concrete double-tee beam bridge.

Figure 5.2.4.2-1 Adjacent Deck Double Tee Beam Superstructure

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Decked Bulb Tees

Decked bulb tee bridges are similar to the Double Tee 

bridges described in the previous section. These girders 

are typically modified bulb tee girders that are placed 

adjacent to one another to form the riding surface of the 

bridge. The modifications to the girders typically involve 

thickening and widening of the top flange and 

modifications to the flange edge to accommodate 

connections. Figure 5.2.4.2-2 is a sketch of a deck bulb 

tee bridge.

The most common connection used to date is a welded tab 

connection. Washington DOT has developed standard 

details for these girders. To date, deck bulb tee girders 

with welded tab connections have mostly been limited to 

low volume roads. This is due in part to concerns over the 

long-term durability of the welded tab connections. 

Research is currently underway at FHWA and New York 

DOT to investigate the use of ultra high performance 

concrete for the flange edge connections (similar to detail 

shown in figure 5.2.4.2-1). This research includes longterm fatigue testing to ensure the viability of this 

connection.

Segmental Bridges 

Segmental construction is becoming more common in the 

United States. Segmental construction involves the 

connection of numerous full-width concrete elements using 

post-tensioning. There are two common forms of 

segmental construction. The first involves cast-in-place 

segmental construction, where traveling forms are used to 

Figure 5.2.4.2-1 Adjacent Deck Bulb Tee Beam Superstructure 

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incrementally cast portions of the bridge. The second 

involves match casting of precast segments that are lifted 

into place and post-tensioned together. This form of 

segmental construction can be considered an ABC method 

because it is faster than cast-in-place segmental 

construction.

Normally segmental construction involves the use of 

elaborate gantry cranes to lift and place the segments 

without the need for shoring or cranes on the ground. This 

is beneficial in locations where the areas under the bridge 

are inaccessible for cranes (i.e. environmentally sensitive 

areas, roadways, railroads, developed areas, etc.). For 

bridges over roadways or railroads, the segmental 

approach can reduce the impacts to the vehicles and trains 

under the bridge, which makes this method a desirable 

ABC approach. Reductions in environmental impacts are 

also a good reason to consider segmental construction.

5.2.4.3. Modular Timber Superstructure Elements and Systems

The United States Department of Agriculture Forest 

Products Laboratory (USDA FPL) has developed standard 

details for timber bridges, including details for prefabricated 

timber panels and beams. There is a significant amount of 

information on timber bridges at the USDA FPL website. 

Users of this Manual are encouraged to visit the Forest 

Products Laboratory website for more information on 

timber bridges (www.fpl.fs.fed.us).

Laminated Deck Span Systems

Laminated deck spans are comprised of adjacent timber 

elements that are laid side by side to form a solid wood 

panel. These panels can be used to span the entire length 

of the bridge. The laminations can be made with sawn 

lumber laid on edge, or glue laminated wood panels. The 

connection between laminations can be made with spikes, 

bolts or transverse post-tensioning. The AASHTO LRFD 

Bridge Design Specifications include design provisions for 

laminated wood deck spans [8]. 

Prefabricated laminated deck span bridges can be built 

very quickly since all the elements are prefabricated, and 

there is no need for casting of concrete. The final riding 

surface is typically a bituminous concrete overlay placed 

over a membrane waterproofing system. Figure 5.2.4.3-1 

shows construction of a laminated wood deck span. This 

was a superstructure replacement in Massachusetts. The 

connection between panels was made using transverse 

bar post-tensioning.

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Figure 5.2.4.3-1 Stress Laminated Timber Deck Span

Top Photo: Panel Erection

Bottom Photo: Final Post-tensioning

(source: Massachusetts DOT) 

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Laminated Girder Deck Systems

Laminated timber decks can be installed on top of timber 

or steel beams. These decks are similar to the deck spans 

except the panels span transversely from beam to beam. 

Laminated wood beams have been in use for many years 

in the building industry. In recent years the use of 

laminated wood beams has become more common in 

bridge structures.

The design of the beams and decks are covered in the 

AASHTO LRFD Bridge Design Specifications [8]. The 

USDA Forest Products Laboratory website contains 

standard plans for laminated wood beams and decks

(www.fpl.fs.fed.us).

As with laminated deck spans, the construction of 

laminated wood decks and beams can be accomplished 

very quickly, since all the elements are prefabricated, and 

there is no need for casting of concrete. The final riding 

surface is typically a bituminous concrete overlay placed 

over a membrane waterproofing system.

5.3. Substructure Elements

Substructures are defined by AASHTO as the portion of the bridge 

between the superstructure and the foundation. For conventional 

bridges, the substructure is normally defined as the portion of the bridge 

below the bridge bearings and above the footings. The following sections 

contain information on typical substructure elements and systems used 

for ABC. These systems include piers, abutments, wingwalls and 

modular culvert/arch systems. 

5.3.1. Piers

Prefabricated pier elements have been used by many state 

agencies. This is due to the difficulty of forming and pouring 

concrete high above the ground and the fact that substructures 

offer opportunities for repetition. There can also be significant 

savings by reducing construction time for substructure work over 

bodies of water or near hazards such as railroads and power 

lines.

5.3.1.1. Open Frame Bents

Construction of open frame bents using cast-in-place 

concrete can be challenging. The shoring and formwork 

systems required to cast the concrete can be a significant 

structure in itself. This is especially true for bent caps. 

Prefabrication of pier elements can save significant time 

during construction. 

Figure 5.3.1.1-1 shows a large bridge built in Florida using 

precast pier caps and columns. The connections were 

made using grouted sleeve reinforcing bar couplers. 

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Figure 5.3.1.1-2 is a sketch of an open framed pier bent 

based on the Utah DOT and PCI Northeast standards. 

Figure 5.3.1.1-1 Precast Open Frame Pier Bent

Top Photo: Overall Bridge

Bottom Photo: Casting of Columns

(source: Splice Sleeve North America Inc.) 

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Figure 5.3.1.1-3 shows the completed construction of an 

open frame pier bent in Georgia. The pier columns and 

caps were constructed using precast concrete. The 

foundations were cast-in-place concrete. The connections 

at the base and top of the columns were made using 

grouted sleeve reinforcing bar couplers. This project was a 

FHWA Highways for LIFE demonstration project. More 

information on this project can be obtained at the FHWA 

Highways for Life website: 

www.fhwa.dot.gov/hfl/summary/projects_summary.cfm.

Figure 5.3.1.1-2 Precast Open Frame Pier Bent Sketch

Figure 5.3.1.1-3 Precast Open Frame Pier Bent

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There are several methods of connections that are in use 

today. See Section 2.3.1 and the FHWA connections 

manual [3] for more information on the various connections 

that have been used. This approach is also being studied 

under the SHRP2 Project R04 entitled “Innovative Bridge 

Designs for Rapid Renewal”. More information on this 

subject will be available once this research is completed.

The construction of precast concrete piers can be 

accomplished very quickly. Using precast concrete 

connection technology, a typical pier bent can be 

constructed in as little as two days once the footings are in 

place.

Pier elements are typically constructed with concrete 

elements; however there are some agencies that have 

incorporated steel elements into pier construction. Tubular 

steel pier bents that are based on off shore oil platform 

technology have been used in Mexico. This technology 

has had limited use in the United States; however some 

states are considering this substructure type.

5.3.1.2. Wall Piers

Wall piers are used in situation where open frame bents 

are not desirable. Examples include piers adjacent to traffic

that may be impacted by errant vehicles or river piers 

where flood debris can accumulate. Prefabrication of wall 

piers has not seen widespread use in the United States; 

however several agencies and the PCI Northeast Bridge 

Technical Committee are investigating the use of wall 

piers.

Figure 5.3.1.2-1 depicts a prefabricated wall pier that is 

under development by the Connecticut DOT. This pier will 

be built adjacent to an existing railroad. ABC is being used 

in part to reduce the costs of railroad flagging at the site 

during construction.

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Figure 5.3.1.2-1 Precast Wall Pier

Top Sketch: Transparent View

Bottom Sketch: Finished Pier

5.3.1.3. Seismic Requirements

Piers are often called upon to resist the majority of seismic 

forces in a bridge. Designs often account for non-linear 

plastic hinging in the pier columns. This places a 

significant demand on prefabricated elements and the 

connections between elements. 

In the past, the design of prefabricated bridge piers for 

seismic events has been a challenge. There simply was 

very little seismic research on prefabricated elements and 

connections. The Utah DOT adopted standards for 

precast pier elements based on the use of grouted splice 

couplers. The performance of these connections is 

essentially the same as conventional cast-in-place 

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concrete. This connection was developed in the vertical 

construction industry over 30 years ago. The couplers are 

embedded in one element and they receive bar extensions 

from the adjacent element. The two elements are 

“plugged” together, braced in place, and the coupler is 

grouted with high strength grout. The popularity of this 

connection stems from the fact that it emulates a 

reinforcing bar lap splice in a typical construction joint, 

which makes the connector very versatile. It can be used 

in many different connections in a typical bridge such as 

abutment stems, backwalls, and wingwalls. Another added 

benefit is that the design of the elements is the same as 

conventional cast-in-place concrete. 

The seismic behavior of these connections has been 

demonstrated through research and testing [51]. Figures 

5.3.1.3-1 depicts a plastic hinge bending test of a 

conventional cast-in-place concrete column to cap 

connection. Figure 5.3.1.3-2 depicts the same test on a 

prefabricated connection made with grouted reinforcing 

splice couplers. A careful review of the data indicates that 

the two results are essentially identical. Both connections 

achieve high levels of ductility. This is an example of how 

a prefabricated connection can be used to emulate a castin-place connection. 

Similar results have been found for other connections. 

One connection that has been studied by several states is 

very similar to the grouted couplers described above [54-

56]. The coupler is replaced with a post-tensioning duct 

that is cast into one of the elements. These connections 

require longer dowel bar lengths than grouted couplers; 

however they are less expensive and allow larger casting 

tolerances on the dowel bars. The diameter of the duct 

may cause interference issues with the pier cap reinforcing 

on heavily reinforced sections, such as single column 

hammerhead pier caps. One way to solve this problem is 

to cap the duct just below the top mat of reinforcing in the 

cap beam. Small diameter grout ports can then be used to 

install the grout in the duct. Figure 5.3.1.3-3 is a sketch of 

a grouted duct pocket connection.

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Figure 5.3.1.3-1 Plastic Moment Connection Test

Cast-in-place Concrete Column-to-Cap [51]

(source: Splice Sleeve North America Inc.) 

Figure 5.3.1.3-2 Plastic Moment Connection Test

Precast Concrete Column-to-Cap [51]

(source: Splice Sleeve North America Inc.) 

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Figure 5.3.1.3-3 Grouted Post-tensioning Duct Connection

Top Sketch: Installation

Bottom Sketch: Transparent View

Other states and the NCHRP have embarked on new research to 

study other connections. The recently published Report entitled 

“Development of Precast Bent Cap Systems for Seismic Regions” 

[11] offers several options for pier cap connections. Washington 

State has also tested connections using grout filled posttensioning ducts [54-56]. They are also testing corrugated precast 

columns ends cast into footings (research is underway). The 

FHWA connections manual [3] also has more information on the 

design of prefabricated connections for seismic loading.

5.3.2. Abutments

Prefabricated abutments are not as common as prefabricated 

superstructure elements or even prefabricated piers. 

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Prefabrication of abutments is feasible. There have been several 

very successful projects where prefabricated elements were used. 

Abutment construction can be a slow process; therefore 

prefabrication offers an opportunity to reduce the overall project 

time. There are different types of abutments in use today in the 

United States. Integral and semi-integral abutments are gaining 

popularity over conventional free standing wall abutments. Both 

types of abutments have been built using prefabricated elements; 

therefore designers can detail prefabricated abutments for virtually 

any abutment configuration that is in use today. The following 

sections contain more information on various types of 

prefabricated abutments.

5.3.2.1. Cantilever

Cantilever abutments serve two purposes. They need to 

retain the soils behind the ends of the bridge and they 

need to support the bridge superstructure. Some wall 

abutments are referred to as stub abutments. These 

abutments are made as short as possible and are installed 

at the top of approach embankments. Stub abutments 

usually only retain soils that are slightly higher than the 

superstructure thickness. 

An example of a prefabricated cantilever abutment is 

depicted in Figure 5.3.2.1-1. This graphical representation 

is based on several details developed by the New 

Hampshire DOT, the Utah DOT and the PCI Northeast 

Bridge technical Committee. All elements are precast 

concrete. The footings are connected to the wall stems 

using grouted reinforcing splice couplers. Corrugated steel 

pipes are used in the abutment stems to reduce shipping 

weight and to facilitate the connection between the wall 

stems and the abutment cap. The abutment cap is 

connected to the wall stems using a reinforcing bar cage 

cast into the corrugated voids. The vertical joints are left 

open or filled with expansive foam. This replicates a 

typical expansion joint in a cast-in-place concrete 

abutment. 

An abutment similar to this was constructed in Epping, 

New Hampshire in less than three (3) days once the 

excavation was complete. The design of the abutment is 

the same as a cast-in-place abutment since the 

connections simply emulate cast-in-place concrete 

construction joints with reinforcing lap splices. 

The Utah DOT has developed standards for cantilever 

abutments. These can be found at www.udot.utah.gov. 

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Figure 5.3.2.1-1 Precast Concrete Cantilever Abutment

5.3.2.2. Spill-Through

The intent of spill-through abutments is to reduce the 

amount of soil pressure on the cantilever abutment by 

installing large voids in the stem. Spill-through abutments 

are similar to piers except the majority of the structure is 

below grade. Information in Section 5.3.1.1 can be used 

for prefabricated bridges with spill-through abutments.

5.3.2.3. Integral and Semi-Integral Abutments

Integral abutments get their name because the abutment 

structure is made integral with the superstructure 

elements. There are two major advantages for the use of 

integral abutments:

• Integral abutments do not have deck joints. This 

eliminates one of the most common deterioration 

areas on bridges.

• Integral abutments transfer the embankment soil 

forces into the bridge superstructure. The 

superstructure has tremendous available capacity for 

axial load; therefore this usually has no effect on the 

superstructure design. Integral abutments are 

normally supported on a single row of piles that are 

designed to move with the bridge during thermal 

cycles and rotate with the beam end under live load. 

The result of this approach is that the abutment does 

not need a spread footing or multiple rows of piles to 

resist the overturning soil forces.

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There are two types of integral abutments. The most 

common is a fully integral abutment where the connection 

to the superstructure is a full moment connection. The 

second type of integral abutment is a semi-integral 

abutment where the moment connection is replaced with a 

pinned connection that allows rotation of the 

superstructure with respect to the substructure. 

An example of a prefabricated integral abutment is 

depicted in Figure 5.3.2.3-1. This graphical representation 

is based on several details developed by the Utah DOT 

and several other states. The concept is based on the use 

of corrugated steel pipes to form voids in the stem and 

complete the connection between the piles and the stem. 

The corrugated void connection was originally developed 

by the Iowa DOT and researched by Iowa State University. 

The results of the research are published in a report 

entitled “Precast Concrete Elements for Accelerated Bridge 

Construction” [12].

Figure 5.3.2.3-1 Prefabricated Integral Abutment

The connection of the superstructure to the integral 

abutment is normally accommodated with a cast-in-place 

concrete closure pour. Some states have used match 

casting combined with transverse post-tensioning to

connect the stem elements. It is possible to design the 

abutment with simple grouted vertical shear keys. The 

vertical reinforcing is then designed to accommodate the 

soil and pile forces. The transverse reinforcement is used 

for distribution reinforcement. This approach was

developed by the Utah DOT. Details for this can be found 

at: www.udot.utah.gov. Appendix A has more information 

on the design of precast integral abutment stems. 

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Semi-integral abutments are similar to integral abutment 

designs in that a portion of the abutment is made integral 

with the superstructure. The semi-integral approach 

includes a joint that allows for un-restrained rotation and 

thermal movement. Several states have built semi-integral 

abutments where the backwall is integral with the beams 

and is located at the end of the beams. The backwall is 

simply cantilevered and lapped behind the abutment stem. 

Figure 5.3.2.3-2 is a sketch of this approach. This system 

lends itself well to superstructure installations using large 

scale installation methods such as SPMTs and lateral 

sliding/skidding. The lack of a significant connection 

between the superstructure and substructure allows for 

tolerance adjustment during the superstructure installation. 

This approach is also being studied under the SHRP2 

Project R04 entitled “Innovative Bridge Designs for Rapid 

Renewal”. More information on this subject will be 

available once this research is completed.

Figure 5.3.2.3-2 Semi-Integral Abutment

5.3.2.4. Geosynthetic Reinforced Soil Integrated Bridge System (GRS)

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The FHWA has developed a unique abutment system that 

integrates the approach roadway fill with the abutment to 

produce a system that functions as one unit. The 

superstructure is placed directly on top of a geosynthetic 

reinforced soil wall. This allows the superstructure to settle 

along with the approach fill, thereby eliminating the needs 

for approach slabs to prevent differential settlement 

bumps. Section 2.1.2 of this manual contains more 

information on GRS abutments. GRS abutments can be 

built in one week or less, because there is no need for 

placement and curing of site cast concrete. Entire bridges 

can be built in approximately 8 weeks. Figure 5.3.2.4-1 

shows a GRS-IBS bridge that was built in Ohio.

5.3.2.5. Seismic Requirements

Figure 5.3.2.4-1 GRS-IBS Bridge Example

Top Photo: GRS Abutment During Construction

Bottom Photo: Completed Bridge (built in 47 days)

(source: Defiance County Ohio) 

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The design of prefabricated abutments for seismic should 

normally follow the same design requirements for 

conventional abutments. This is because most 

prefabricated abutments are designed and detailed to 

emulate conventional abutments.

The elements that make up the abutment and the 

connections between the abutment stem and the footing 

on cantilever abutment needs to be able to develop the 

forces that are imposed during seismic events. Spill 

through abutments may need to be designed and detailed 

in a similar fashion as piers since the construction is 

similar. 

The design of GRS bridge abutments for seismic events is 

provided in the FHWA Geosynthetic Reinforced Soil 

Integrated Bridge System, Interim Implementation Guide. 

This can be found at: 

www.fhwa.dot.gov/publications/research/infrastructure/

structures/11026/index.cfm

5.3.3. Wing Walls and Retaining walls

Wingwalls and retaining walls are types of earth retaining 

systems. There are many different types of systems for 

constructing earth retaining walls. The most common types of 

walls include:

• Concrete Cantilever

• Concrete Gravity

• Mechanically Stabilized Earth

• Prefabricated Modular

• Anchored 

• Cantilever Sheeting and Soldier Pile

The AASHTO LRFD Bridge Design Specifications [8] includes 

design information about each one of these wall systems. This 

section will include information on prefabrication of retaining wall 

systems and how they can be used in accelerated construction 

projects. 

Some of the systems shown in this section are proprietary; 

however in most cases, there are multiple manufacturers that can 

produce similar walls. Some states allow multiple wall systems for 

larger wall projects by bidding the walls as a Design-Build product, 

where the manufacturer designs the wall based on the constraints 

of the site. 

5.3.3.1. Precast Concrete Cantilever

Conventional cantilever walls are normally comprised of a 

reinforced concrete footing connected to a reinforced 

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concrete stem. These wall types are common for 

wingwalls on bridges that are relatively short in both length 

and height. Figure 5.3.3.1-1 depicts as sketch of a precast 

concrete cantilever wall, based on details developed by the 

New Hampshire DOT. These details were used on the 

Epping Bridge in New Hampshire, where the entire bridge 

was constructed in only eight days. 

The construction time for a typical wall of this type can be 

accomplished in as little as two days (for a typical wingwall 

of reasonable length).

Figure 5.3.3.1-1 Precast Concrete Cantilever Wingwall

5.3.3.2. Modular Precast

Modular precast concrete wall systems are walls that are 

made up of prefabricated elements that are joined in 

different ways to create a wall system. 

There are two distinct types of prefabricated wall systems 

that are primarily in use today, Mechanically Stabilized 

Earth and Modular Block retaining walls. There are also 

other systems in use and more in development. All of 

these wall systems include prefabricated elements; 

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therefore they are well suited for prefabricated bridge 

projects. 

Mechanically Stabilized Earth Systems (MSE)

MSE systems normally use prefabricated wall panels that 

are connected to earth reinforcing devices. These devices 

engage the soil mass behind the wall face to create a soil 

mass gravity wall. There are also wall systems that use 

GRS fabric, wire mesh or natural vegetation in place of the 

wall panel facings. The construction of these walls can 

progress rapidly because the system is built while the soil 

is being placed behind the wall; thereby combining two 

processes into one.

MSE walls systems may be proprietary. There are multiple

manufacturers that make this type of system; therefore 

public bidding of these wall systems is possible. Most 

agencies have standard details or approved wall products; 

therefore individual details from each state are not 

presented in this manual. 

Figure 5.3.3.2-1 depicts a typical wall section for a 

mechanically stabilized earth wall. Designers should 

contact each state

allowed for use.

 to determine which wall systems are 

Figure 5.3.3.2-1 Typical MSE Wall Details 

Modular Block Systems

Modular block retaining walls are a form of gravity retaining 

wall in which the cast-in-place concrete is replaced by 

modular reinforced concrete modules that interlock to form 

a wall system. The system resists soil forces by the mass 

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of the wall and sometimes by the mass of soil placed within 

voids in the blocks.

As with MSE systems, modular block walls are normally 

proprietary. Many states have approved product lists for 

these wall systems; therefore individual details from each 

state are not presented in this manual. Figure 5.3.3.2-1 

depicts a typical wall section for a modular block wall. 

Designers should contact each state to determine which 

wall systems are allowed for use.

5.3.4. Modular Culvert/Arch Systems

Culverts represent a significant portion of the structures found on 

typical highways. Many states currently use prefabricated arch 

structures. The most common forms are precast concrete box 

culverts and corrugated steel arch pipes. 

A new generation of modular culvert systems is gaining popularity 

due to the desire to provide a bottomless stream bed by regulatory 

agencies. These systems consist of arch structures or three sided 

frame structures supported on strip footings.

5.3.4.1. Precast Arches and Three Sided Frames

Several manufacturers have developed precast concrete 

arch and three sided frame systems. These systems 

consist of precast strip elements placed side-by-side to 

create the bridge span. Most systems are filled with 

granular backfill placed over the precast elements to 

complete the structure. In some cases, these structures 

have been slid under existing bridges without closure of 

the overpass roadway. Once in place the voids between 

Figure 5.3.3.2-2 Modular Block Wall Example (T-WALL®)

(source: The Neel Company) 

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the two structures can be quickly filled with granular fill 

after removal of the bridge, or filled with flowable fill without 

removal of the existing bridge.

Most precast systems are complete span elements that 

include the vertical stems. Other systems consist of two or 

three precast arch elements connected in the field to 

complete the arch. Some of these systems are developed 

by private companies and others have been developed by 

state agencies.

In most cases, the arches are designed as a two-hinge 

arch. The connection to the footings is designed as a 

pinned connection. The arch base is simply inserted into a 

keyway in the footing and grouted in place.

Figure 5.3.4.1-1 depicts an arch system called the 

Con/Span® Bridge System. This system, including the 

arch elements, the spandrel walls, the wingwalls and the 

footings, can be completely made with precast concrete 

elements. 

Construction of a typical precast arch structure can be 

completed in as little as one week, since all elements 

(including the footings) can be made with precast concrete.

Figure 5.3.4.1-1 Con/Span® Bridge System

(source: Contech Construction Products, Inc.) 

5.3.4.2. Steel Arches and Pipes

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Corrugated steel arches and pipes have been in use for 

many years. Steel plate arches can span significant 

distances in order to span rivers, roadways or even 

railroads. The arches can be designed as a culvert or as a 

bottomless frame supported on concrete footings.

Construction of a typical steel plate arches can be 

accomplished in as little as one to three days depending 

on the water handling needs, the complexity of the shape 

and the number of plates required to make up the 

structure.

5.3.4.3. Box Culverts

Many state agencies have developed standard details for 

precast concrete box culvert systems. The American 

Society of Testing and Materials (ASTM) Specification 

C1577 entitled “Precast Reinforced Concrete Monolithic 

Box Sections for Culverts, Storm Drains, and Sewers 

Designed According to AASHTO LRFD” [41] can be used 

to design and detail these systems. This ASTM 

specification is for single cell box culverts. For multi-cell 

box culverts, designers typically butt single-cell units sideby-side. 

The use of precast concrete box culverts has become 

commonplace across the country; therefore, significant 

details are not presented in this Manual. Readers are 

urged to contact state highway agencies for more 

information on the details used in their region.

The construction time for a precast concrete box culvert 

can vary depending on water handling needs. For simple 

sites, the construction can be completed in one to three 

days.

5.4. Foundations

This section will describe in general the types of foundation elements 

that are commonly used on ABC projects that involve new foundations. 

On some ABC projects, such as superstructure replacement projects, the 

foundation can be re-used. In these cases the foundation capacities 

should be investigated. This section has been broken out into typical 

foundation elements that are used on most bridges. The AASHTO LRFD 

design specifications [8] define constructed foundations as spread 

footings, driven piles and drilled shafts. 

5.4.1. Common Deep Foundations

Most state agencies design bridges with deep foundations that are 

either supported on driven piles, micropiles, continuous flight 

auger piles, or drilled shafts. Pile foundations are normally 

capped with concrete footings in order to provide a stable platform 

to support piers, walls and abutments. For short span bridges, the 

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piles bents can be used (piles directly connected to the bent cap). 

Pile bents are cost effective and can be built quickly since there is 

no need for a footing. Most pile bents are constructed with 

precast concrete piles.

Drilled shafts are becoming more popular. Large diameter drilled 

shafts can be used to support individual concrete pier columns, 

thereby eliminating the need for a concrete footing. The 

Washington State DOT has developed ways to connect precast 

concrete pier columns to drilled shafts. The method involves the 

use of non-contact lap splices in a small closure pour at the base 

of the column. The column reinforcing is kept to a smaller 

diameter than the shaft reinforcing, thereby allowing the column 

reinforcing cage to be placed within the top of the shaft 

reinforcing. This connection was studied under a research project 

with the University of Washington [42].

5.4.2. Foundation Challenges

The construction of foundations can present several significant 

challenges depending on the site constraints. ABC can be used 

to minimize the difficulty of addressing some of these challenges. 

The following sections contain information on some of the more 

common challenges. 

5.4.2.1. Earth Retention

Excavation for foundations can be difficult, especially if 

there are adjacent structures, roadways or rails. Typically 

the retention of earth is handled with temporary sheet 

piling. Once in place, the new foundations can be 

constructed within the temporary structures. 

In some situations, prefabricated elements can be used to 

retain soil and be part of the finished structure. Two 

examples of this are as follows:

Precast Concrete Sheet Piling

The Florida DOT has developed standards for precast 

concrete sheet piling. The precast panels have 

interlocking edges that prevent differential lateral 

movement between panels. Once driven into place, the 

panels are capped to complete the structure.

Cellular Steel Sheet Piling Abutments

Several agencies have constructed bridges using cellular 

steel sheeting structures. There are two types of systems 

in use. The first is closed cell sheeting, which is comprised 

of steel sheeting driven in an oval or circular configuration 

to form a cell. Once in place, the cell is filled with 

compacted soil and a concrete cap to complete the 

abutment. Open cell sheet pile abutments are similar, 

except that the sheeting is placed in a “C” configuration. 

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The ends of the sheeting elements are anchored into the 

approach fill using a proprietary system.

5.4.2.2. Deep Water

Construction of bridges in deep water has always been a 

challenge. Long-span bridge technology has in-part grown 

out of the need to span over deep water so that shallow 

water foundations can be used. Historically, deep water 

foundations were built using deep cofferdams and 

caissons. The advent of large size driven piles and large 

diameter drilled shafts has opened up the possibility of 

building deep water foundations without deep cofferdams 

or caissons. Prefabricated elements can be used to cap 

the piles or shafts well above the mud-line of the waterway. 

These structures can also be used as a shallow cofferdam 

to allow for placement of footing reinforcing and concrete. 

Section 5.4.3.3 includes information on precast concrete 

pier box cofferdams.

5.4.3. Prefabricated Foundation Elements

5.4.3.1. Spread Footings

Precast concrete spread footings are a relatively new 

concept in bridge construction. The New Hampshire DOT 

developed a precast spread footing system for the Epping 

Bridge project. These footings were placed over a 

prepared subgrade on leveling bolts and then grouted into 

place. The joints between the footing elements are made 

with shear keys that are filled with non-shrink grout.

The Utah DOT has also developed similar standard details 

for this application. The Utah standards make use of 

flowable fill to bridge the gaps between the bottom of the 

footings and the subgrade. Figure 5.3.3.1-1 is a sketch of 

a retaining wall with a precast concrete spread footing. 

The size of footings for bridge piers can get quite large, 

which makes transportation of precast concrete footings 

difficult or even impossible. Figure 5.3.1.1-2 depicts a four 

column pier bent. Four individual footings are shown (one 

for each column). If a single continuous footing was 

required, a single footing would be too large for shipping 

and handling. A continuous footing can be achieved by 

using precast concrete under the columns only. These 

smaller footings are designed to support the dead load of 

the bridge. Reinforcing bars can be extended from the 

precast footings, and a cast-in-place closure pour can then 

be completed during the erection of the remaining portions 

of the bridge. The completed continuous footing is 

designed to support all other loads. The same approach 

can be used for single column piers. Small footings can be 

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placed under the column and extended as the pier 

structure is being constructed.

5.4.3.2. Pile Cap Footings

Precast concrete can be used for concrete pile caps. 

Several states have used grouted pockets to connect the 

piles to the cap. The FHWA Connections Manual [3] 

contains several details for pile cap connections.

Recently, new details have been developed that make use 

of corrugated steel pipe voids that are based on research 

that was completed in Iowa [12]. This research showed 

that a void made in a precast concrete footing with a 

corrugated steel pipe can provide very large punching 

shear resistance. Research on seismic connections has 

also demonstrated that these voids can develop large 

moment resistance as well [11]. 

Figure 5.4.3.2-1 is a sketch of a precast concrete footing 

placed on precast concrete piles. Corrugated steel pipe 

voids are used to make the connection between the piles 

and the footing.

Figure 5.4.3.2-1 Precast Pile Cap Footing

(with corrugated steel pipe void connection)

5.4.3.3. Precast Pier Box Cofferdams

Several projects have been designed where a precast 

concrete pier box was used to dewater the area where the 

drilled shaft connects to the bridge footing. For example, 

the new Providence River Bridge in Providence, Rhode 

Island, has precast concrete pier boxes that were hung 

from the 8 foot diameter drilled shafts that allowed the 

construction of the footings in the dry. The precast box 

was set over the drilled shaft and sealed with a small 

tremie pour around the drilled shaft. These systems can 

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eliminate the need for complicated cofferdams and 

dewatering systems, especially in deep water. When built 

using HPC, the precast box forms can serve as an 

additional corrosion protection system for the new pier 

footing.

Figure 5.4.3.3-1 shows the construction of the Providence 

River Bridge. Figure 5.4.3.3-2 shows the details of the 

installation of the pier box. The construction started with 

the installation of large pipe hanger clamps that were hung 

from the edges of the drilled shaft casings. A steel 

alignment framing was then set on the clamps that were 

hung from the pile casing, followed by the installation of 

precast floor and side panels. After that, the joints were 

grouted and a tremie pour installed. This system gave the 

contractor a work space to set reinforcing and to pour the 

footing concrete. The use of the precast concrete pier 

boxes saved the contractor many months of in the 

construction of the foundations. 

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Figure 5.4.3.3-1 Precast Concrete Pier Box Cofferdam

Top photo: Exterior View

Bottom Photo: Interior View

(source: Cardi Corporation) 

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Precast side walls Temporary Steel Framing

Drilled Shaft

Frame Support Clamp

Hanger Rods

Tremie Pour

Figure 5.4.3.3-2 Precast Concrete Pier Box Cofferdam Installation

Top view: Plan

Bottom view: Section

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Chapter 6 Miscellaneous Bridge Elements

Minor bridge elements can have an impact on the construction and long-term 

performance of a bridges built with ABC methods. This chapter will describe the effects 

that these elements have on bridges built using ABC techniques.

6.1. Deck Overlays I Riding Surface Quality

There are two approaches to deck riding surfaces in the United States. 

With the advent of low permeability High Performance Concrete (HPC), 

many states are building bridges without supplemental wearing surfaces 

(bare concrete decks). This approach is most likely born out of long-term 

issues with bituminous concrete overlays on bridge decks. In the past, 

agencies placed bituminous concrete overlays on bridge decks to reduce 

roadway noise in urban residential environments, improve the riding 

surface, and to protect the deck from deterioration. The problem with this 

approach is that the bituminous overlay is porous and not waterproof by 

any means. In fact, the overlay tends to trap moisture on top of the 

concrete deck. This can lead to accelerated deterioration of the deck due 

to the infiltration of water and deicing salts.

The European approach to deck protection is to use bituminous overlays 

combined with high quality waterproofing membranes. This approach has 

yielded long lasting bridge decks that can meet the AASHTO goal of a 75 

year service life. Several states have adopted this approach with similar 

results. Anecdotal information on bridges built with bituminous overlays 

and waterproofing systems in Connecticut in the 1960’s indicated that 

they have performed very well over the last 50 years. 

Certain ABC methods can lead to problems with the riding surface quality 

of bridge decks. The use of prefabricated bridge deck elements will

inevitably require the use of joints between elements. Construction of the 

elements will also require reasonable fabrication and erection tolerances. 

These issues will lead to an un-even riding surface. Several states have 

used diamond grinding to smooth out the deck after installation of the 

elements. This required that the concrete cover in the elements be thick 

enough to accommodate the grinding operation. The Utah DOT has 

found that diamond grinding can improve the riding surface, but the 

finished product is not as smooth as a cast-in-place concrete deck. 

Diamond grinding can be problematic in that it removes the concrete fines 

at the surface and exposes the larger aggregate. This may cause 

problems in northern envrionments in the future as the deck is exposed to 

freeze thaw cycles and deicing chemicals.

Overlays can be used to eliminate the need for grinding. For states that 

prefer smooth concrete riding surfaces, thin concrete overlays can be 

used. Bituminous concrete riding surfaces can be used in states that 

allow their use. The application of a concrete overlay will require 

additional time and/or bridge closures in order to place the overlay. For 

very fast construction projects, this can be accomplished on subsequent 

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weekends after the bridge is re-opened to traffic. The Virginia DOT has 

developed a very-early-strength latex modified concrete overlay. 

Research has shown that this material can be placed and cured in as little 

as three hours and provide low permeability and high bond strength [43]. 

Thin overlays will ensure a better quality final riding surface on the bridge 

deck. The overlay can be thought of as the last tolerance adjustment 

during the construction of the prefabricated structure.

6.2. Bridge Deck Expansion Joints

Bridge deck expansion joints have long been the source of premature 

deterioration of bridge decks and supporting framing. Most states are 

designing bridges using integral abutments and continuous 

superstructures in order to eliminate expansion joints. On larger bridges, 

it is inevitable that deck expansion joints will be required. Bridge deck 

expansion joints can be placed into two categories:

• Joints placed within the deck overlay system: These consist of 

various asphaltic plug materials and epoxy header systems 

combined with glands or seals.

• Joints embedded into the deck or supported directly by the 

superstructure framing: These systems tend to more elaborate 

and can accommodate larger movement. They typically consist of 

armored seals, finger joints, or modular expansion joint systems.

The effect of joint systems on ABC projects depends on the category. 

Joints that are placed within the overlay are typically not affected by ABC 

methods. The joint can be installed in the same manner as with 

conventional construction. For embedded joint systems, it is difficult to 

install the joints within the prefabricated elements to the required 

tolerances. The best way to alleviate this issue is to install the joints 

system within small closure pours after the installation of the 

prefabricated bridge deck. Details should be developed to allow for 

adjustment of the joint system in the field in order to accommodate the 

fabrication and erection tolerances of the prefabricated elements.

6.3. Bridge Bearings

On conventional bridge construction, bridge bearings are set during the 

erection of beam elements. The design and construction of the bearings 

normally does not include vertical adjustment for construction tolerances. 

This is normally accounted for in the gap between the top of girder and 

the deck, which is often referred to as the deck haunch. 

On certain modular prefabricated ABC projects, the deck is fabricated 

along with the girders prior to installation. This is applicable to full 

superstructure bridge moves and for modular superstructure element 

bridges. For these bridges, the bearings can be used to adjust the 

elevation of the girders and the finished riding surface. Bearing 

adjustments can also be used to properly seat elements that have more 

than three support points. A three dimensional plane can be defined by 

three coordinates. If an element has more than three support points, the 

additional points must be on the same plane in order for the element to 

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seat properly. Adjustments need to be made to account for the fact that 

the support plane will not be exact.

There are various ways to make these adjustments. Figure 6.3-1 is a 

sketch of an adjustable elastomeric bearing on a modular steel bridge 

superstructure element. The sole plate is welded to the girder in the

fabrication shop (tan plate). The bearing has a top plate (grey). The 

white plate is a shim plate used to make up the gap between the bearing 

top plate and the modular unit sole plate. In this case, the contractor 

could fabricate extra shim plates of varying thicknesses in order to 

account for field tolerances.

Figure 6.3-1 Adjustable Bearing Detail

This is just one example of how to account for field tolerances. Other 

methods can be used, as long as the anticipated fabrication and erection 

tolerances are accounted for.

6.4. Drainage Assemblies

Designers typically try to detail bridges without drainage assemblies. 

Drainage assemblies have a tendency to clog and fail, thereby allowing 

roadway water to spill onto beams and substructures. On long span 

bridges, bridges with flat grades where run-off widths are unacceptable, 

or bridges built on sag vertical curbs, it may be necessary to install 

drainage systems. It is possible to install drainage assemblies into 

prefabricated deck elements. The standard details that are used for 

conventional bridges can normally be applied to prefabricated elements. 

Minor adjustment may be required in order to facilitate the fabrication 

process.

6.5. Barriers and Railings 

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Barriers and railings can be a significant problem with ABC projects. The 

major issue is the lack of crash tested prefabricated barrier systems. The 

FHWA Connections Manual [3] contains more information on the issues 

with connecting barriers and railing to prefabricated elements. There are 

several ways to address barrier and railing issues that will be discussed in 

the following sections. 

6.5.1. Crash Testing Requirements

The FHWA requires that all parapets and railings on the National 

Highway System (NHS) be crash tested. The AASHTO LRFD 

Bridge Design Specifications [8] require that all barriers and railing 

be crash tested in accordance with the requirements outlined in 

NCHRP Report 350 entitled “Recommended Procedure for the 

Safety Performance Evaluation of Highway Features” [44]. This 

document is published by the Transportation Research Board and 

is available for download at the Transportation Research Board 

online publication website. These requirements have limited the 

number of prefabricated barrier systems that can be used. Some 

states have used non-crash tested barriers and railings designed 

according to the AASHTO LRFD Bridge Design Specifications [8] 

for non-NHS projects.

6.5.2. Concrete Barriers

Difficulties can arise on bridges with concrete curbing or concrete 

barriers. Some states have anchored precast concrete barriers to 

prefabricated decks by through bolting the parapet to the deck. In 

this scenario, the bolt projects down below the deck and is 

secured with a nut and an anchor plate. This type of connection 

has been problematic. If the bolts are placed in pre-formed holes, 

water can migrate through the hole and corrode the anchor plate 

and the underlying framing. If this connection is used, it should be 

properly sealed. 

The Utah DOT has designed and built several prefabricated 

bridge decks with the concrete barrier cast onto the deck in the 

fabrication shop. Figure 6.5-1 shows the erection of one of the 

bridges. The dead load distribution of the parapet weight needs to 

be addressed, since it may not be the same as a conventional 

cast-in-place construction. The fascia beam may end up carrying

more dead load than what is normally assumed in design. The 

designers need to account for this in the design of the girders. It 

may be possible to mitigate this through the use of leveling bolts. 

By specifying a uniform torque on all bolts, the dead load of the 

barrier can be shifted to interior girders.

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Figure 6.5-1 Precast Deck Panel with Integral Barriers

(source: Utah DOT) 

There have been issues with alignment of the barrier face when 

this method of construction was employed. The complexity of 

cross slope and tolerances for width at the gutter line and top of 

parapet can make fit-up of these elements difficult. This is mostly 

an issue with deck panels that have two barriers as shown. On 

bridges where a longitudinal closure pour was used, the fit-up has 

been much better. A longitudinal closure pour can be used to 

make up for casting and erection tolerances, as well as provide a 

location to accommodate a roadway crown angle point.

Effect of joints in precast parapets:

If the system shown in Figure 6.5-1 is employed, the detailing of 

the barrier needs to be based on a barrier end zone. The 

AASHTO LRFD Bridge Design Specifications [8] have 

requirements for barrier end zones that are different from interior 

span zones. This may require different reinforcing than what is 

used on conventional barrier designs. 

6.5.3. Metal Railings

On ABC projects, prefabrication of metal railings is not normally 

an issue. Anchor rods can be installed in the deck panels in the 

fabrication shop. If a metal railing is to be placed on top of a 

concrete curb, the same issues outlined in Section 6.5.2 would 

apply.

6.5.4. Barriers on MSE and Modular Walls

Prefabricated MSE and Modular Block walls are very common. In 

some instances, the top of the wall is used to support a concrete 

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barrier. Most states have developed standard details for precast 

concrete barriers that are set on top of the modular wall. The 

resistance of the barrier to vehicular impacts is normally 

accommodated through the use of a simple cast-in-place moment 

slab.

6.6. Utilities 

The accommodation of utilities on ABC projects can have an impact on 

the design and detailing. Utilities can also have an adverse impact on the 

construction methods chosen. The best option for utilities is to remove 

and relocate them prior to the start of construction. This leaves the 

contractor unobstructed access to the site. In the case of a deck or 

superstructure replacement project, it may be possible to temporarily 

support the utilities and work around them during erection. Once in place, 

the utilities can be reattached to the new elements.

In some cases, it will not be feasible to remove or relocate utilities. This 

can have an impact on the construction methods that are feasible. 

Overhead wires can be problematic for crane operations. If overhead 

wires cannot be moved, designers should investigate other installation 

methods such as gantry cranes, lateral slide-in systems, longitudinal 

launching systems, or installation using SPMTs (see Section 2.4).

Underground utilities can also affect ABC methods. Placement of cranes 

on top of fragile underground utilities may be problematic. It is possible to 

span over these utilities through the use of steel plates and/or crane 

mats. Concern has arisen over the use of SPMTs over underground 

utilities. Steel plating has been used to protect utilities; however it can 

become impractical for longer travel paths. SPMTs have the ability to 

distribute the load over a large area with many wheel sets. The utility 

concerns can be alleviated by specifying a maximum wheel load in the 

project specifications that is acceptable to the utility company. 

In some cases, utility companies can temporarily shut down service 

during short construction periods. Gas and water mains are sometimes 

designed with redundancy, thereby allowing short term closure without 

significant impact to the utility network. ABC can be used to limit the 

length of time of these closures.

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Chapter 7 Construction

The nature of ABC projects is that there is more emphasis on temporary works and 

specialized equipment. Standard construction processes and construction engineering 

methods need to account for these differences. This section will explore these 

differences and how construction processes need to change to account for ABC 

construction.

7.1. Shoring Systems and Temporary Works

AASHTO has two published documents on temporary works. The first 

relates to design of temporary works [45] and the second relates to 

construction practices [46]. These documents are based on conventional 

construction methods, although many of the provisions in these 

documents can be applied to ABC projects. Shoring systems, earth 

retaining systems, and temporary support systems can be designed and 

constructed using these provisions. 

On most projects, the design of shoring and temporary works is the 

responsibility of the contractor. On design-build and CMGC projects this 

responsibility may be undertaken by the design team. The reason for this 

approach on design-bid-build projects is that the design team is not privy 

to the equipment and materials that are available to the contractor. In any 

case, the design and detailing of shoring and bridge temporary works 

should be undertaken by a professional engineer that is experienced in 

the design of such structures.

7.1.1. Shoring for Large-scale Bridge Moves 

(using SPMT, lateral sliding, launching, etc.)

Large-scale prefabrication and moving of structures is not 

addressed by the AASHTO documents; however there are 

resources available to assist designers and constructors. The 

FHWA SPMT Manual [2] contains significant information on the 

process of designing and moving bridges with SPMT’s. Much of 

this information is also applicable to bridge moves using other 

technologies such as lateral sliding. The Utah DOT has also 

developed a manual on design and construction using SPMT 

technology [7].

Shoring systems for large-scale bridge moves are significant 

structures in themselves. The design and construction of these 

systems needs to follow many of the same steps that a permanent 

structure would require. Several important aspects of the design 

include geotechnical investigations and design, wind loading 

analysis, and stability analysis. In most cases, the design of the 

shoring systems is left up to the contractor. It is important that the 

design of these systems be accomplished by a registered 

professional engineer with experience in the design of large-scale 

shoring systems.

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The materials for shoring ABC bridges may also be somewhat 

different than conventional construction. Shoring companies often 

try to make use of materials that are on hand. One piece of 

shoring equipment has migrated from another industry. 

Prefabricated shipping containers have been used on several 

ABC projects for temporary abutments and for falsework on top of 

SPMTs. Figure 7.1.1-1 shows the moving of the Providence River 

Bridge, which weighed more than 6 million pounds. Shipping 

containers were extensively used for the shoring system. 

Shipping containers offer the following benefits:

• High load capacity: Container ratings can range from 

approximately 400 to 500 kips.

• High Shear Capacity: The corrugated sides of the 

containers can accommodate large shear forces (both 

horizontal and vertical).

• Adaptable: Containers are modular and designed to be 

stacked in groups.

• Readily Available: Shipping containers are available all 

over the country.

• Low Cost: These containers can be rented at reasonable 

rates.

Some contractors have used these containers for on-site storage 

when they were used for temporary abutments. The key structural 

feature of these containers is that the vertical loads typically need 

to be applied to the corners of the container. Figure 7.1.1-1 

shows red spreader beams on top of the top containers. These 

are used to transfer the load to the corners of the containers.

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Moving of unusual structures may require temporary bracing 

systems. The Providence River Bridge is a network tied arch. 

The key features of a network arch are the diagonal hanger cables 

and the lack of vertical compression members. In order to move 

this structure, the lifting points needed to be placed 100 feet from 

the end supports, so that the barges could clear the bridge piers. 

The uncoated vertical members shown in Figure 7.1.1-1 are 

temporary compression members that were designed to resist the 

unusual support position. The entire structure needed to be 

analyzed with these members in place to ensure that the stresses 

were kept within tolerable limits.

Another important aspect of shoring for SPMT bridge moves is the 

stiffness and make-up of the framing below the superstructure. It 

is often impractical to provide one support point for each beam in 

a bridge cross section. Figure 7.1.1-2 shows an SPMT bridge 

move in Utah. In this case, a transverse carrying beam was used 

to transfer the load from each beam to two support points. A 

second transverse distribution beam was then used to transfer the 

load to four SPMT’s

Figure 7.1.1-1 Shipping Containers Used for Shoring 

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Figure 7.1.1-2 Support Framing for SPMT Moves

(source: Utah DOT) 

The relative stiffness of the support framing compared to the 

stiffness of the bridge superstructure makes the analysis of this 

situation a complex problem. The design of the girders is often 

based on relatively equal dead load to all girders. The flexibility of 

the support framing makes this assumption invalid. The girders 

directly under the support points will inevitably carry more load 

than the other girders. In this case, a three dimensional analysis 

of the entire system is required in order to determine the stresses 

in all the members (including the superstructure).

There are ways to ensure that the load is distributed to the girders 

equally. The first approach is to install a hydraulic jack system 

that is interconnected to a common manifold. By placing equal 

pressure at each jack, the support reactions can be kept equal. 

This approach is often used for bridge jacking systems. The 

second approach is to place varying height shims between the 

girders and the top carrying beam. The height of the shims can 

be calculated based on the calculated deflection of the carrying 

beam under uniform support loads. Once loaded, the bottom 

flanges of the girders will be kept in their uniform load position.

7.1.2. Geotechnical Investigations

The large scale movement of bridges requires additional 

geotechnical investigations. Normally, bridge designers only 

investigate the soil directly beneath the proposed foundations. On 

large-scale bridge moves, additional geotechnical investigations 

need to be undertaken at the fabrication site and along any 

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proposed travel paths. It is important to note that the tire loads on 

most SPMTs are similar to standard truck tires; therefore 

pavement distress should not be an issue. SPMTs can be driven 

over relatively rough terrain including dirt pathways. In some 

cases, steel plates are used to spread the tire loads evenly to the 

supporting soil.

7.2. Acceleration of Submissions and Reviews

The use of accelerated project delivery methods can place a premium on 

contract management. Many states are exploring the use of electronic 

data submissions. On conventional construction projects, significant 

amounts of paper plans, specifications and reports are generated and 

distributed for review. With today’s modern technology, the use of paper 

can be significantly reduced and even eliminated.

7.2.1. Electronic Data Transfer

There are several forms of electronic data files. The use of 

computer aided design (CAD) files and word processing files for 

data transfer is normally discouraged. This is due to the ease of 

modifications to these types of files, which could lead to problems. 

For instance, it would be easy for a reviewer to accidently erase 

line work and text from a CAD file. 

The availability of viewing software can also be a hindrance to the 

use of these files. If the reviewer did not have the particular CAD 

software, an electronic review would not be possible.

Other forms of electronic files are preferred since they are closer 

to permanent paper files, and the software for viewing the 

documents is readily available. The following are the most 

common forms of files used for construction documents:

• Tagged Image File Format (TIFF) is a bitmapped image 

format that contains descriptive information about the 

image. 

• Joint Photographic Experts Group (JPEG) is a file type that 

is a compressed digital photographic image. The 

resolution can be adjusted to reduce the overall file size 

with minimal loss of quality.

• Portable Document Format (PDF) is a file format 

developed by Adobe Systems Incorporated. It has 

become an open standard for document exchange.

There are also other file formats in use; however the most 

common file standard in use today is PDF. Most major CAD 

software packages now have the capability of generating PDF 

output. It is now possible to generate entire plan sets that are 

indexed using CAD software and Adobe software. Many offices 

also use document scanners on a regular basis. Many of these 

scanners can generate TIFF, JPEG or PDF files from scanned 

images. TIFF and JPEG files can be viewed on virtually all 

personal computers. PDF readers are available on-line free of 

charge. 

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7.2.1.1. Electronic Shop Drawing and Submittals

The use of electronic submittals can greatly reduce the 

time required to review and approve construction 

submissions. A typical submission schedule can be 

reduced from weeks to days. It is possible to review and 

mark-up plans using software; however many reviewers 

still prefer to mark-up drawings. This can still be done if a 

document scanner is available for electronic generation of 

marked up plans. One convenient feature of electronic 

submittals is that the reviewer need not print the entire set 

of drawings for mark-up. Some reviewers are not required 

to comment on all sheets. For instance, a materials 

engineer may only be interested in the materials 

specifications on one sheet. This engineer would only 

need to view and possibly print that sheet as opposed to 

the entire set.

Even if reviewers prefer to print entire submissions, they 

can print reduced size prints for the review. Tabloid size 

(11”x17”) is a common paper size for plan reviews. The 

Utah DOT has standardized all of their contract and review 

drawings to tabloid size. This will save paper and 

eliminate the need to handle large rolls of plans. It also 

simplifies the scanning process. Many office copiers can 

now easily scan tabloid size paper.

7.2.1.2. Digital Stamps and Signatures

One of the most significant issues with electronic plan 

submissions is the need for certified and stamped 

drawings. For example, many plans require professional 

engineering stamps and signatures, or approval stamps 

and initials. Some software packages can produce 

electronic digital signatures and approval stamps. These 

are password protected applications that only the certifying 

personnel can apply. 

Some states may have statutory requirements for physical 

hand written signatures. This does not necessarily mean 

that electronic submissions cannot be used. In this case, 

the preliminary submissions can be reviewed 

electronically. Once all comments are resolved, a hard 

copy document can be produced with the appropriate 

signatures. This process is not as efficient as full 

electronic approvals, but it is faster than paper 

submissions.

 

7.2.2. “Intent to build” Drawings

In the bridge construction industry, there is a common requirement 

that a shop drawing must be generated for each element that is 

fabricated. The idea stems from the historical practice of using 

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the actual drawing on the shop floor to build the element. Many 

modern fabrication shops have moved toward computer 

applications including Computer Numerical Control (CNC) 

equipment. This eliminates the need to have individual paper 

drawings for some shop applications. In addition, on many 

projects, there is a significant repetition of certain elements. The 

generation of individual plan sheets for each similar element is 

redundant and superfluous. 

Most contracts place the responsibility for fabrication accuracy on 

the contractor and fabricator. This normally includes the accuracy 

of dimensions and materials on shop drawings. This requirement 

brings into question the need for detailed review of each drawing 

by the design engineer. Some agencies have investigated the 

use of “Intent to build” drawings. These drawings are intended to 

demonstrate the overall fabrication process without individual 

drawings for each element. Often one element is completely 

detailed and a table is generated that includes the variable for 

each element. On a large bridge, the total number of drawings 

that are submitted for review can be significantly reduced. This 

saves time in the generation of the drawings and the review by the 

designer. 

7.3. Materials Testing on ABC Projects

On ABC projects where construction durations are reduced from months 

to days, the need for accelerated materials testing is critical. Curing of 

concretes and grouts used for connecting elements and systems is 

normally the critical path in an ABC project. On some projects, the 

strength of concretes and grouts need to be measured in increments of 

hours or minutes instead of days. 

7.3.1. Accelerated Testing Protocol

The extreme timelines on some ABC projects will require 

accelerated testing protocols. This will lead to the need for 

increased sampling levels so that tests can be run on more 

frequent and shorter intervals. The designers should carefully 

specify the amount of samples and the required testing intervals 

for ABC projects.

In many cases, testing laboratories are situated in centralized 

locations. Complications may arise if the construction site is 

located in a remote area. Some agencies have required that 

contractors supply and set-up a remote testing facility that is near 

the bridge site. This helps to expedite the testing process and get 

the approval information to the field quickly.

7.3.2. Concrete Maturity Method

A maturity method has been developed to assist in the testing 

process for cast concrete. The maturity method equates a 

maturity index to the concrete strength of a mix. The concept is 

based on the proven assumption that concretes of equal maturity 

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will have equal strengths. The maturity index is a function of the 

age and temperature of the concrete. During mix development, 

multiple tests are run on samples in order to develop a strengthmaturity curve. This method does not normally replace the 

requirement for concrete cylinder testing; however it can aid in the 

determination of when to test the cylinders. 

In order to use this method, temperature sensors need to be 

embedded in the placed concrete. Temperatures need to be 

measured during the entire curing process. From these readings, 

the maturity index can be calculated and the concrete strength 

estimated based on the mix development curve.

7.3.3. Load Indicating Washers for Steel Structures

Bolting of structural steel elements can be a time consuming 

process. Most states use the “turn of the nut method” or the 

“calibrated torque wrench” method for tightening bolts. 

Regardless of which method is used, the inspection of the 

completed connection needs to be completed. This may require 

marking nut positions during tightening process (turn of the nut 

method), or checking the final torque (calibrated torque wrench 

method). These inspections can slow down the installation time 

since the work crews have to work in concert with the inspectors 

or wait for inspectors to approve an installation prior to moving on 

to the next task.

Several companies have developed specialized washers that are 

manufactured with bumps. The bumps are specifically designed 

to crush at the specified bolt tension. These washers can 

expedite the installation process for bolted connections since the 

inspector is not required to spend significant time checking the 

connection. A simple visual inspection is only required after the 

connection is complete.

7.4. Fabrication

Prefabrication of materials is a major component of ABC. It has been 

demonstrated that prefabrication can save significant time; however there 

are issues that need to be addressed with certain ABC projects. This is 

especially true for quality and fabrication tolerances.

It is important to understand that there are lead times for prefabricated 

elements. This is especially true for bridges built using accelerated 

project delivery methods. Ample time should be given for development 

and review shop drawings, and element fabrication and delivery. Project 

schedules should account for these efforts. 

7.4.1. Plant Certification

The importance of fabrication plant certification cannot be 

stressed enough. The quality and proper fit-up of prefabricated 

elements is critical to the success of an ABC project. Plant 

certifications ensure that a level of quality control and assurance is 

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following for every element that is produced. Many states specify 

PCI certification for concrete elements and AISC certification for 

steel elements.

7.4.2. Near-site Casting Certification

The use of certified fabrication plants for prefabricated 

elements can be problematic for bridges in remote 

locations. The cost of shipping large prefabricated 

elements over long distances can lead to cost increases 

and time delays. One way to resolve this issue is to allow 

the establishment of a near-site fabrication yard. 

Some states are investigating the prequalification of 

general contractors for near-site fabrication. It may be 

possible to work with the certifying institutes to establish a 

certification process for this scenario. Another option is to 

allow a certified fabricator to set up a remote fabrication 

yard near the bridge site. 

There is one potential benefit to allowing a contractor the 

ability to prefabricate elements. In this scenario, the 

contractor is required to take on the risk of proper fit-up, 

which can lead to better quality. 

7.4.3. Tolerances

Tolerances can be the source of many problems in accelerated 

bridge construction projects. Field fit-up is also one of the major 

concerns of agencies who are considering an accelerated bridge 

project using prefabricated elements. Designers of a 

prefabricated bridge project should assume that nothing is perfect 

and that tolerance will need to be accounted for in every detail. 

The Utah DOT has developed typical tolerance limit details for 

typical prefabricated bridge elements. These drawings can be 

found at: www.udot.utah.gov. 

The following sections discuss the issues with tolerance in 

prefabricated bridge elements. 

7.4.3.1. Element Tolerances 

A common misconception by designers of prefabricated 

bridge projects is that the elements are built to exact 

dimensions. In fact, all prefabricated elements are built 

within some tolerance. The designers should be aware of 

the specified construction tolerances for cambers, sweep, 

and overall dimensions in all elements. The locations of 

holes, inserts and blockouts are also very important. 

Prefabrication and accelerated bridge construction projects 

usually do not need to be designed with elements having 

stricter tolerances than conventional construction. The 

tolerances specified by the various industries are usually 

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sufficient. A designer of prefabricated bridges should be 

familiar with the design tolerances in the state in which 

each project is located, and account for these tolerances in 

the design and details. Consideration should also be given 

to whether tolerances used in conventional construction 

can be increased for prefabricated construction to simplify 

fit-up in the field.

7.4.3.2. Dimensional Growth 

If designers do not account for element tolerances, a 

phenomenon called “dimensional growth” can occur. This 

is due to a build-up of dimensional tolerances over several 

or many elements. For example, if ten panels that are 

each ten feet wide are placed side by side, the overall 

length of the system will typically be greater than 100 feet. 

This is due to the width tolerances and the tolerances of 

the edges of the adjoining pieces. Match casting of 

concrete projects can minimize this problem, but minor 

dimensional growth of the structure is inevitable. To 

address this problem, designers should compensate for 

member tolerances in the joint details or allow for minor 

overall variation in the structure dimensions. 

Another form of dimensional growth has to do with the 

detailing of tolerance limits for multiple protruding 

elements, post-tensioning ducts, and embedded 

attachments. It is important to specify that the location 

tolerance be measured from a common working point. If 

center-to-center spacing tolerances are used, the layout 

error tolerance can become additive and affect the 

connection of the elements.

7.4.3.3. Hardware Tolerances

The location of hardware in prefabricated elements can be 

critical to the success of the project. Some hardware 

elements are more critical than others; therefore, designers 

need to specify the location tolerances of all hardware and 

attachments.

Post-tensioning Systems

Post-tensioning systems usually require the installation of 

strand or thread bars after the erection of the individual 

elements. It is important to specify the tolerance of the 

location of the ducts, especially at the ends of the element. 

Match casting is sometimes used to keep these tolerances 

to a minimum. If small grout keys or closure pours are 

used, there is a greater likelihood of post-tensioning duct 

offset at the joints. In this case, it is recommended that 

ducts be oversized to allow for minor offsets in the duct at 

the joints.

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Grouted Reinforcing Splice Couplers

Couplers require a certain degree of tolerance that is 

attainable in normal precast concrete construction. The 

typical coupler can accommodate minor variation in bar 

locations. It also may be possible to use an oversized 

coupler to provide even greater tolerance. This approach 

normally provides approximately 1⁄2 inch of tolerance 

adjustment, which is well within normal tolerances for 

precast elements. Designers should contact coupler 

companies to determine the appropriate coupler 

tolerances.

Precast manufacturers can maintain the level of tolerance 

between pieces by using frames and jigs as templates to 

position and support the reinforcing steel and couplers. If 

a design requires the connection of a precast element to a 

field cast portion of the bridge, it is recommended that the 

precast producer provide a template jig to the general 

contract to ensure proper fit-up in the field during erection. 

The designer should clearly specify the responsible parties 

for this approach.

Embedded Attachments

The level of tolerance for embedded attachments is a 

function of the tolerance for the attaching member. If the 

attachment is for a utility pipe hanger that has adjustability, 

then the tolerance will not be as strict as it will be for other 

elements. Designers should clearly identify the required 

level of tolerance for all embedded attachments.

7.4.4. Lifting/Moving Elements

Prefabricated elements are typical very heavy. Special lifting 

hardware may be required to safely lift elements without causing 

damage. The design of lifting hardware is typically the 

responsibility of the contractor or fabricator. For heavy elements, 

conventional lifting hardware such as bent reinforcing bars will 

most likely not be sufficient. Specialized lifting hardware with 

embedded reinforcing bars will most likely be required. Careful 

attention should be given to the location of the lifting device and 

the angle that the anticipated load will be applied. Some lifting 

devices are specifically not designed for large lateral loads. This 

is especially important for elements that are scheduled to be cast 

flat and then tilted up into a vertical position. This would apply to 

elements such as wall stems.

The effects of lifting on the prefabricated elements also need to be 

checked. This is also typically the responsibility of the fabricator, 

since the fabricator selects the lifting points and hardware. The 

PCI Design Handbook (Chapter 5) [47] contains more information 

on lifting and handling of precast concrete elements. This manual 

includes procedures for checking member stresses, 

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recommendations for dynamic effects during handling, and form 

stripping forces. 

The PCI Manual also includes recommended factors of safety for 

handling stresses. There are two criteria specified, one for “no 

cracking” and another for “no discernable cracking”. Designers 

should specify which of these criteria is required for each element. 

There is a cost associated with each criteria, which should be 

considered by designers. It may be appropriate to use the lesser 

“no discernable cracking” criteria for secondary elements such as 

footings. Appendix A includes an example of calculating lifting 

stresses on a precast concrete deck panel.

7.4.5. Workmanship

The most important aspect of workmanship is the fabrication of 

elements that are within tolerance. This does not imply that other 

forms of workmanship are not important. Elements that are not 

fabricated within tolerance simply will not fit together in the field. 

This can have a significant impact on the construction timeframe, 

especially for projects with extremely tight construction windows. 

Fabricators may wish to dry fit the elements in the fabrication yard 

in order to ensure that the elements will fit together in the field.

7.5. Erection Issues

Erection of bridge beams and girders are well understood by owner 

agencies. Erection of prefabricated bridge elements brings about 

different challenges. The speed of construction often precludes the 

opportunity to set up large cranes. Specialized equipment and/or smaller 

cranes are required for some projects. Tolerances and adjustments are 

also critical to the success of an ABC project. This section will cover the 

issues of erection of elements on ABC projects.

7.5.1. Responsibilities

The responsibilities for erection and handling of prefabricated 

elements should be clearly defined in the contract documents. 

The most important aspect of erection procedures is to require 

that the erection engineer be experienced in erection calculations 

and a licensed professional engineer.

7.5.1.1. Designer

The designer is typically not involved with the development 

of the erection plan and supporting calculations. This is 

due to the fact that the designer does not know what 

equipment will be used for the construction. 

On complex projects, some agencies require that the 

designer develop an erection plan as part of a 

constructability study. In this case, the designer simply 

selects reasonable construction equipment from catalogs. 

From this, an erection plan can be developed including 

preliminary lifting calculations.

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Once a project is in construction, the designer is typically 

responsible for the review of the erection plans and 

calculations. In the case of Design/Build or CMGC 

contracting, the designer is part of the construction team; 

therefore the erection plans may become the responsibility 

of the designer.

7.5.1.2. Contractor

The contractor is typically responsible for the development 

of erection plans and calculations. The erection plans 

needs to account the following items as a minimum:

• Available equipment

• Lifting hardware

• Underground utilities 

• Overhead utilities

• Adjacent wetlands

• Available right of way 

It is not unusual for the contractor’s erection plan to be 

significantly different from the erection plan envisioned by 

the designer. Contractors can be very resourceful in the 

development of an erection plan. This is controlled by the 

availability of equipment for the project.

7.5.1.3. Fabricator

In most cases, the fabricator is not involved in the erection 

process. If the fabricator is also the erection contractor, 

then they should follow the same procedures and 

provisions noted above.

7.5.2. Large-scale Bridge Lifting

Section 2.4 describes the various methods for structure 

placement. In many cases, the structure is temporarily supported 

in locations that are not congruent with the final support locations. 

This type of placement method can have significant effects on the 

bridge structure. The FHWA SPMT Manual [2] contains some 

recommendations on lifting and handling stress calculations.

The Utah DOT has studied the effects of SPMT bridge moves on 

superstructures. During the initial group of SPMT bridge 

installations, the department installed numerous strain gages on 

the major structural elements. The goal was to monitor the 

internal stresses during the entire installation process. Utah State 

University was asked to review the data and report back on their 

findings. Figure 7.5.2-1 shows the results of one of the bridge 

moves. It was a single span steel bridge that was cast while endsupported, and lifted at a significant distance from the beam ends. 

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Figure 7.5.2-1 Strain Measurements During an SPMT Bridge Move

(source: Utah DOT and Utah State University) 

The gage shown was located on the steel girder near the lifting 

point. The gages were set to zero after the deck was cast and 

while the bridge was supported at the ends. The initial strain is 

due to the transfer of the bridge from the end supported condition 

to the SPMT supported condition. This represents a very large 

strain that equates to a steel stress of approximately 55 ksi. At 

first glance, this may seem excessive, but it is important to note 

that the strain represents a reversal. The area in question was 

stressed in compression when the gage was attached. The large 

strain represents the change from positive bending to negative 

bending.

The bridge was supported on SPMTs for four days. During this 

time two things happened. The structure was moved several 

times, and the temperature changed daily. The thermal strain, 

which is represented as semi-sinusoidal curves, is not related to 

an internal stress change since there was no restraint in the 

system. This simply represents the length change of the girder 

when exposed to temperature variations. The jagged portions of 

the curve represent the strain due to dynamic effects. The Utah 

State University study showed that the dynamic strains were in the 

range of 5% to just over 10% of the dead load strain at the lift 

points (points of maximum stress). Based on this study, The Utah 

DOT now specifies a dynamic stress allowance by specifying that 

the dead load of the structure be increased by 15%. It is 

recommended that this dynamic effect also be applied to other 

large scale bridge placement methods.

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A secondary part of the Utah State University study was to 

investigate the torsional effects in the bridge during the SPMT 

bridge move. It was found that the torsional effects were 

negligible, as long as the bridge warping was kept within the 

specified tolerances in the UDOT SPMT Manual [7].

7.5.3. The Effect of Tolerances and Adjustability

As previously stated, all prefabricated elements are built to a 

tolerance. The key to design and construction is to account for 

the tolerances in the design of the joints and the layout of the 

elements. 

The joint width is directly affected by the element tolerance. If an 

element has a length tolerance of +1/2”, then the nominal joint 

width should be designed to accommodate adjacent elements that 

are either both at the maximum length tolerance or both at the 

minimum length tolerance.

The same holds true for the horizontal joints. Minor tolerances 

can build up during the construction of a bridge. This can result in 

beams being too low, or uneven roadway profiles. In order to 

control this, designers should specify element erection elevation 

tolerances. The Utah DOT standard details for substructure 

element contain recommended erection tolerance limits. These 

can be found at: www.udot.utah.gov. 

7.6. Field Inspection

ABC projects bring about a need for accelerated construction inspection. 

Short duration construction timeframes also require the need to have all 

levels of project management make decisions quickly. The key to this 

effort is to empower decision making at all levels of the project team. 

This section will explore options that designers and agencies can adopt to 

improve the construction management of ABC projects.

7.6.1. Accelerated Decision Making

The lack of ability to make decisions can adversely affect the 

progress of an ABC project. On some conventional construction 

projects, the field personnel are given very little decision making 

authority. This leads to long construction processes with large 

amounts of downtime.

The goal on ABC projects is to accelerate the decisions making 

process. One way to do this is to have high level personnel on 

site at all times, although this may not be practical in some 

situations. Another tool that is available is an issue resolution 

ladder. Figure 7.6.1-1 shows a schematic resolution ladder. If an 

issue arises on a project, every attempt is made to resolve the 

issue at the lowest level. The process starts at the lowest level 

and if the two parties at that level cannot resolve the issue, it 

moves up the ladder until the issue is resolved. By having this 

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ladder clearly defined, decision making can be expedited. The 

key to success on an ABC project is to have experienced and 

competent personnel at the lowest possible levels in the ladder. 

The decision making authority for these personnel should be 

clearly identified to all parties.

Level Contractor Agency

6 President Commissioner

5 Vice President Chief Engineer

4 Regional manager District Engineer

3 Project Manager Construction Office Manager

2 Field Superintendent Lead Inspector

1 Foreman Field Inspector

Figure 7.6.1-1 Construction Issue Resolution Ladder

The following are typical guidelines for use of an issue resolution 

ladder:

1. Resolve all simple issues at the field level, whenever 

possible. The team should identify the level of decisions that 

need to move up the ladder beyond this level prior to the start 

of construction.

2. Escalate issues up the ladder whenever:

• the partners cannot agree on the decision.

• the partners do not have the authority to make the 

decision.

• an issue is threatening to delay the project.

• an issue is threatening to damage the partnering 

relationship.

3. Agree to disagree, and disagree without being disagreeable.

4. Escalate issues evenly up both sides of the ladder, and let go 

of the issue.

5. Do not skip levels or "leap-frog" up the ladder.

6. Upper level partners should insist that the ladder (chain of 

command) be used.

7. Avoid "swoop-downs" by partners higher up in the chain of 

command. 

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8. Keep partners at lower levels informed of progress as it 

develops in the resolution process.

9. Return the agreed upon decision to the field personnel as 

quickly as possible, once the issue is resolved.

The basis of this ladder is that the agency is responsible for the 

construction management of the project. Design build and CMGC 

projects would require a different, but similar ladder. It is 

important to note that the engineer of record is part of this 

process. Any issues that involve design aspects of the project 

should be coordinated with the engineer of record.

7.6.2. Staff Training

ABC projects differ from conventional construction projects; 

therefore training of staff needs to be different as well. Two of the 

key differences in ABC construction are the use of grouts and 

post-tensioning systems. 

It is helpful to have construction staff involved during the design of 

an ABC project. This allows the inspection staff to understand the 

reasons for the ABC processes, and it gives them an opportunity 

ask questions and receive answer before the project is bid. In 

many cases, the field inspection personnel can provide valuable 

insight into the potential problems that may occur. 

ABC workshops can be held where all parties are invited to 

discuss a particular project or a proposed construction process. 

These workshops should be run by experts in ABC techniques 

and attended by designers, construction inspectors, fabricators, 

and contractors. The Utah DOT has had great success with ABC 

workshops, which is part of the reason for the successes that they 

have had with ABC projects. 

The following sections contain information on these processes 

and the require training for field inspection personnel.

7.7. Grout Placement and Curing

The connection of prefabricated bridge elements often involves the use of 

grouts. Grouting of small voids is not routine in the bridge construction 

industry. Improper grouting of voids can have an impact on ABC 

schedules, and an even more dramatic effect on the long-term durability 

of the finished product. These installations are often on the critical path of 

construction. It is important to execute proper grouting procedures in 

order to keep the project moving forward. There are several approaches 

that can be followed to minimize the potential for grouting problems. 

7.7.1. Small Void Grouting

There is no one grout and no one grouting technique that is 

applicable to all projects. Grouts can range from dry pack grouts 

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that are installed by hand, to flowable grouts that are poured into 

intricate voids. 

On some occasions, the Texas DOT has required that a 

contractor demonstrate proper grout placement before the actual 

construction starts. The contractor is required to build a full scale 

wood mock-up of the void that is to be grouted. The contractor 

then installs the grout using the proposed techniques. Once the 

grout has cured, the mock-up is disassembled and the grout is 

inspected. If voids or segregation are found, the process is 

repeated until a proper technique or material is found.

Field inspectors also need to be well versed in all grouting 

techniques including proper mixing and placement. Some grout 

manufacturers have published grout installation manuals, which 

can be a good resource for the field inspection staff. In some 

instances, it may be necessary to have a grout manufacturer 

technician come out to the field to train the inspection staff on 

proper installation techniques, or be present during initial grouting 

operations.

7.7.2. Grouting of Post-tensioning Ducts

The installation and grouting of post-tensioning ducts has been 

problematic over the years. There have been several failures of 

strand and anchoring devices that were attributed to poor 

installation techniques and low quality materials. The FHWA has 

developed a manual entitled “Post-Tensioning Tendon Installation 

and Grouting Manual” [48]. This manual is a valuable resource for 

field personnel on projects that involve post-tensioning. The 

American Segmental Bridge Institute (ASBI) also publishes 

manuals on post-tensioning installation and grouting. Some 

states now require that a certified ASBI Grout Technician be 

present during all post-tensioning duct grouting procedures. 

Another approach is to specify that workers with past grouting 

experience be on-site during grouting operations. 

7.8. High Early Strength Concrete

As with grouting, it is inevitable that small closure pours will be part of 

many ABC projects. These pours are normally used to connect major 

elements and systems that require significant room for adjustment. 

Typical examples would include the connection of a superstructure to a 

substructure in an integral abutment or pier, or a closure pour near a 

bridge deck joint. 

There have been problems with shrinkage and cracking of high early 

strength mixes. The Utah DOT has found moderate cracking in many 

closure pours. These cracks can lead to deck leakage and premature 

deck deterioration. Figure 7.8-1 shows a closure pour in Utah. The left 

side of the photo shows precast concrete deck panels. The right side 

shows the closure pour concrete. There are cracks spaced at 

approximately 2-3 feet along the edge of this pour. 

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The cause of the cracking is related to the need for high early strength in 

the mix. In order to get early strength gain, mix designers may design a 

mix for a much higher strength in order to achieve an early specified 

strength. This approach is acceptable since the contract specifications 

only require a minimum strength. For example, a contractor may use an 

8000 psi mix for a specified 4000 psi deck in order to reach the specified 

strength in a short period of time. The high cement content in such a mix 

tends to lead to more drying shrinkage. The restraint of the adjacent 

precast panels causes a build-up of tension stress in the closure pour 

concrete. When the internal tension stress in the closure pour exceeds 

the tensile capacity of the concrete, a crack will form.

There are two approaches to the design of closure pours and the 

concrete mixes that can be followed:

• The first approach is to simply design the connection for the 

required final strength. The issue will force the contractor to 

overdesign the mix in order to attain the minimum required strength 

in a short period of time. This will inevitably lead to more shrinkage 

and cracking.

• Second, the connection can be designed for a lower strength 

concrete. The mix can be based on a higher strength; however the 

specifications could allow opening of the bridge at lower strengths. 

For example, the Massachusetts DOT recently designed a deck 

closure pour for an ABC project. The closure pour was designed 

with a concrete strength of 2000 psi. The concrete specifications 

were still set at 4000 psi minimum; however the contractor is 

allowed to open the bridge when the strength reached 2000 psi. 

Extensive mix design and testing protocols are being use to ensure 

that the mix will not produce significant cracks and that it will 

achieve the required strength after the bridge is opened to traffic. 

The second approach is preferred because it will result in a concrete that 

has less susceptibility to cracking.

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Figure 7.8-1 Cracking in Closure Pour Concrete

The Utah DOT has been studying the issue of cracking in high early 

strength concretes. They have set the following strength performance 

criteria for the closure pour concrete:

• Attain a 6-hour compressive strength of 2500 psi

• Attain a 7-day compressive strength of 4000 psi.

• Develop a mix that contains shrinkage compensating additives 

that will meet a specified department shrinkage performance test.

The shrinkage component of this mix is not intended to be “non-shrink”. 

The goal is to produce concrete with low shrinkage characteristics.

Typical agency prescriptive concrete mixes cannot meet these 

requirements. It may be possible to develop a prescriptive concrete 

mix; however it may be difficult to come up with one mix that can work 

for all suppliers. The recommended approach is to develop a 

performance specification. Given a set of parameters, a producer can 

develop a specialized mix based on the materials that are available. 

This approach is similar to what is typically done in precast fabrication 

plants. Each plant has mixes that have been developed and approved 

by the agency.

7.8.1. Mix Design Approach

The Utah DOT and the Massachusetts DOT are using a 

performance specification approach for high early strength 

concrete. The basis of this approach is to obtain high early 

concrete strengths while minimizing shrinkage in concrete. This 

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approach is based in part on research that was completed in 

Washington State in a paper entitled “Mitigation Strategies for 

Early-Age Shrinkage Cracking in Bridge Decks” [49]

The following is the preliminary Utah DOT approach for mix 

design of high early strength concrete:

1. The mix design for high early strength concrete should be 

developed by each concrete producer. This is based on 

the fact that the aggregate source and size have an impact 

on the final product. The department will evaluate each 

mix for approval.

2. It is recommended that the water to cementitious materials 

ratio (w/c) be kept to 0.4 or less. 

3. Use between 4 and 7 percent-entrained air.

4. The size of the aggregate should be maximized for the 

intended use. Mixes with coarse aggregates as large as 

11⁄2” are recommended. Multiple mixes that use different 

coarse aggregate sizes may be required for different pour 

locations.

5. Shrinkage compensating admixtures should be used. 

6. The use of expansive materials such as aluminum powder 

and oxidizing iron aggregates is not recommended.

The Massachusetts DOT specification has similar requirements 

and is included in Appendix C of this manual.

As previously stated, cracking in closure pour concrete is typically 

a result of shrinkage of the confined concrete. The surrounding 

precast concrete will restrain the closure pour concrete. The key 

to minimizing cracking is to have the concrete gain tensile strength 

faster than the development of internal shrinkage stresses. 

Typical ASTM shrinkage tests measure the shrinkage of 

unconfined concrete. A simple specimen is cast and it length 

change is measured over time. This test method is not an 

appropriate measure of the potential for cracking in confined 

concrete. 

In order to determine the susceptibility of a concrete mix to 

confined shrinkage cracking, a test must be used that includes 

confined concrete. The AASHTO construction specifications 

include a confined shrinkage test entitled AASHTO T334-08 

Practice for Estimating the Crack Tendency of Concrete [50]. 

Figure 7.8.1-1 is a sketch of an AASHTO ring test setup. This test 

consists of a ring of concrete cast around a 12” diameter, 1⁄2” thick 

steel pipe that is 6” tall. A 3” thick concrete ring is cast around the 

pipe. Strain gages are installed on the steel ring to measure the 

build-up of stress in the ring as the concrete shrinks. When 

cracking occurs in the concrete, the stresses in the steel ring will 

drop off indicating the exact time of the crack.

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Figure 7.8.1-1 AASHTO Ring Test for Confined Concrete Shrinkage

It should be noted that this test will not guarantee that a 

confined concrete pour will not crack. It will measure the 

relative cracking resistance of different mixes. A goal for 

this test may be to develop a mix that does not crack within 

a specified timeframe such as 14 or 28 days. The 

Massachusetts specifications use the ring test to identify 

potential candidate mixes. The final acceptance is made 

after a full-scale confined closure pour is cast and cured. 

Cracking limits are specified for this closure pour concrete.

Minor cracking may occur in closure pours even with a low 

shrinkage concrete mix. The key is to minimize the 

amount of cracking. Many states have specification 

requirements for sealing and repair of cracked concrete. 

The most common repair procedures include the use of 

methacrylate crack sealers, or epoxy injection methods.

There is research that is underway at this time that is 

investigating different materials for grouted joints and 

concrete closure pours. This work is being done at the 

Virginia Polytechnic Institute and State University. The 

research includes an investigation of leakage of water 

through joints in precast deck elements. Agencies should 

investigate the results of this research once it is completed 

and adjust construction specifications and materials 

accordingly. 

7.8.2. Accelerated Curing

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Curing methods can have a significant impact on high early 

strength gain. The use of applied heat during curing can 

be used to expedite strength gain provided that the same 

heat can be successfully incorporated into the field poured 

concrete. The precast concrete industry has been using 

accelerated curing methods for many years. This often 

involves the use of steam to increase the temperature of 

the mix during curing. 

Portable heating units have been developed that can 

increase the temperature of field placed concrete. 

Tarpaulins and space heaters are not recommended 

because they do not apply uniform and consistent heat, 

especially during cold weather pours. These units can be 

used in conjunction with the concrete maturity method of 

measuring early strength gain (see Section 7.3.2). 

If heating is proposed, the contractors should submit 

detailed heating procedures including the uniform 

application of heat to all portions of the concrete pour, and 

provisions for preventing overheating of the concrete.

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Chapter 8 Long Term Performance of Prefabricated 

Elements 

There is little debate in the bridge design and construction industry over the durability of 

prefabricated elements. Plant produced products have been in use for many years, and 

have performed admirably. The concerns expressed by agencies are mostly with regard 

to the connections used between the elements. This section will explore the past 

performance of ABC projects and how ABC affects management of these bridges.

8.1. Inspection Preservation, and Maintenance

The inspection preservation, and maintenance of bridges built with ABC 

techniques differs somewhat from bridges built using conventional 

methods, although the differences are minor. The majority of bridges 

built with prefabricated elements are designed based on the technique of 

emulating cast-in-place concrete. In most cases, prefabricated 

connections mimic a construction joint in conventional construction. This 

means that the bridges will perform essentially the same as a cast-inplace concrete structure.

There are a few potential inspection, preservation, and maintenance 

activities associated with prefabricated element bridges; however based 

on performance to date, these activities are not seen as being more 

significant than those on bridges built using conventional construction 

techniques. . Grouted joints in substructure elements could potentially be 

subject to long-term deterioration. One example that is often cited is the 

joint at the top of a footing. These areas tend to be subjected to moisture 

and salt spray. The condition of the grout joint should be monitored 

during normal inspection cycles. If deterioration is found, the joint can be 

re-pointed, which involves removal of the grout to sound material and 

replacement with new grout. For connections in critical locations such as 

slat water splash zones, the designer may consider stainless steel 

reinforcing bars to eliminate potential corrosion problems. 

If there is a concern for the long-term durability of this joint in particular, 

there is a solution to provide better protection. Figure 8.1-1 is a sketch of 

a column to footing connection that is based on a detail developed by the 

New Hampshire DOT. The actual connection is recessed into the footing. 

Once the connection is complete, the entire recess is filled with grout or 

concrete to provide protection that is in addition to the actual grout.

Several states have used post-tensioning for connections for 

prefabricated bridge elements. Many of these states also have posttensioned structures in their inventory. The inspection, preservation, and 

long-term maintenance of post-tensioned prefabricated elements should 

be the same as normal post-tensioned structures.

Some states are concerned with the inspection and long-term 

preservation and maintenance of precast bridge deck panels. Experience 

has shown that with proper design and detailing, these panels can 

provide a long service life with no maintenance beyond what is done for 

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conventional bridge decks. Designs based on the provisions of Section 

9.7.5 of the AASHTO LRFD Bridge Design Specifications have provided 

excellent performance. Section 8.2 will cover case studies of the longterm performance of precast concrete deck panels designed to these 

provisions.

Figure 8.1-1 Recessed and Grouted Footing Joint

8.2. Durability of Modular Systems

This section will include case studies of several ABC projects that have 

been in service for extended periods of time. The projects contain details 

that are commonly used today. Projects include the Edison Bridge in Fort 

Meyers, Florida (15 years) and two bridge deck replacement projects in 

Connecticut (almost 20 years). A number of other bridges built with fulldepth precast concrete decks have been in service for more than 10 

years, and the performance has been excellent. 

One notable bridge is the Woodrow Wilson Bridge that crosses the 

Potomac River near Washington, D.C. This bridge carries Interstate 95 

and is one of the most heavily traveled bridges in the country. In the 

1980’s, the deck was replaced with full-depth precast lightweight concrete 

slabs [38]. The Maryland DOT has noted that the deck had performed 

very well under the most severe environment until it was replaced by the 

new Outer Loop Bridge in the summer of 2006. 

One of the key features of precast concrete construction, when compared 

to cast-in-place construction is the lack of restraint during curing. 

Individual elements are allowed to cure in a relatively unrestrained 

condition. The only restraint is the friction between the elements and the 

forms. In cast-in-place concrete construction, the casting of fresh 

concrete against previously placed elements leads to a build-up of 

internal stresses during curing, which often leads to cracking in the 

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concrete. The most common form of this type of cracking is transverse 

cracking in bridge decks caused by restraint of the girders. Prefabricated 

concrete elements are placed after shrinkage has occurred; therefore the 

potential for shrinkage cracking is eliminated. This will have a significant 

impact on the long-term durability of the elements.

8.2.1. Case Studies in Durability

To date, many bridges have been built using ABC techniques. 

ABC projects date back to the 1960s and 1970s. This section will 

showcase several ABC projects that have been in service for a 

number of years in order to demonstrate the long-term durability of 

prefabricated elements 

8.2.1.1. Joints in Substructure Elements

As previously stated, the concern over the durability of 

joints in substructure elements has focused on joints near 

the base of columns and wall stems. The Florida DOT 

constructed a high level viaduct in Fort Meyers in 1992. 

The bridge carries Route 41 across the Caloosahatchie 

River. The river is tidal in this area; therefore the structure 

is exposure to brackish water. The piers for this bridge 

were constructed with precast concrete columns and 

precast concrete pier caps. The connections were made 

with grouted reinforcing splice couplers and grouted joints. 

Figure 8.2.1.1-1 shows the bridge during and after 

construction.

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Figure 8.2.1.1-1 Edison Bridge

Top Photo: During Construction

Bottom Photo: Just Prior to Opening

(source: Splice Sleeve North America Inc.) 

The environment for this bridge can be considered severe. 

Florida has had a history of bridges with pier column 

deterioration problems. A review of the bridge inspection 

files showed that this bridge is still in good condition, even 

after 15 years in service. No deficiencies in the joints were 

noted.

8.2.1.2. Joints in Precast Concrete Deck Panels

The Connecticut DOT replaced a deck on a bridge in the 

Interstate 84/ Route 8 interchange in Waterbury, CT (CT 

Bridge 03200). The deck was replaced in 1991 using full 

depth precast concrete bridge deck panels. The bridge is 

a six span curved structure. This bridge deck was built 

well before the development of the AASHTO LRFD Bridge 

Design Specifications; however the detailing and design 

are essentially the same as what is currently specified in 

Section 9.7.5 [8]. The decks span transversely across the 

superstructure and are connected using grouted shear 

keys combined with longitudinal post-tensioning. Figure 

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8.2.1.2-1 shows and aerial view of the bridge. Figure 

8.2.1.2-2 shows a recent photo of the underside of the 

bridge deck.

Figure 8.2.1.2-1 Connecticut Bridge 03200

Figure 8.2.1.2-2 Underside of Bridge 03200 after 19 Years in Service

This bridge deck was protected with a waterproofing 

system and a bituminous concrete overlay. A review of the 

photo in Figure 8.2.1.2-2 shows that the deck is essentially 

in pristine condition. The hint of staining in the photograph 

is overspray from a bridge painting project after the deck 

was replaced. There are no signs of leakage at the joints 

and the deck is virtually un-cracked. Two other bridges 

were built in Connecticut in the early 1990’s using the 

same details. These bridges are also in excellent

condition.

8.2.1.3. Large-scale Bridge Moves

The durability of bridges installed using SPMT methods 

has one potential drawback. Depending on the location of 

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the lifting points, the bridge deck and parapets can

experience cracking. The early SPMT bridge moves in 

Utah were lifted at approximately the third points of the 

bridges, which resulted in large overhangs during the

bridge moves. Figure 8.2.1.3-1 shows one of the Interstate 

80 Westbound bridges during the installation. The large 

overhangs led to cracking in the decks and parapets. The 

reason that cracking was allowed was based on the

understanding that the cracks would close after the bridge 

was set. This actually was the case. Upon setting, the 

cracks closed significantly. They are similar to shrinkage 

cracks in bridge decks built with cast-in-place concrete.

Figure 8.2.1.3-1 Utah DOT I-80 Westbound Bridge Installation

(source: Utah DOT) 

Figure 8.2.1.3-2 shows the underside of one of the bridge 

decks. There are a significant amount of cracks that are 

leaking. The cracks are small and not any different than 

typical shrinkage cracks in bridge decks. The leakage is 

most likely due to inadequate performance of the

waterproofing system and wearing surface overlay. This 

type of leakage was found on several decks including castin-place structures. 

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Figure 8.2.1.3-2 Typical Cracking on the I-80 Bridges

(source: Utah DOT) 

One year after the SPMT installations, the adjacent I-80 

eastbound bridges were built using conventional methods. 

Figure 8.2.1.3-3 shows a side-by side comparison of the 

two bridges. The bridge on the right was installed using 

SPMTs, and the bridge on the left was cast-in-place. The 

cracking is obviously worse on the cast-in-place deck. 

This does not necessarily demonstrate that concrete decks 

on SPMT bridges are better than decks cast on

conventionally constructed bridge. It does demonstrate 

that deck cracking can occur on all bridge structures that 

employ casting of a deck on top of girders. 

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In order to minimize the potential for deck and parapet 

cracking, the Utah DOT has changed its policy regarding 

SPMT bridge moves. They now limit the overhangs to 

approximately 20 percent of the span length. Some 

designers limit the concrete stresses in the deck during 

transport to less than the modulus of rupture. Bridges built 

to these new criteria have had little or no discernable 

cracking. 

Figure 8.2.1.3-3 Side-by-side Comparison

Bridge on right installed with SPMTs

Bridge on left built with conventional construction methods

(source: Utah DOT) 

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Chapter 9 Design and Analysis

9.1. LRFD Design

The design of most ABC elements and systems follows traditional LRFD 

design specifications. The individual elements are typicall designed as if 

they were built using CIP construction techniques. The design of 

connections in reinforced concrete elements are typically based on the 

AASHTO requirements for mechanical reinforcing devices in that the 

device is required to resist 125% of the specified yield strength of the 

reinforcing bar. This chapter will cover common prefabricated elements 

and the design issues associated with each element type. This chapter 

will also address issues that are not specifically covered in the AASHTO 

design specifications, and recommendations to designers for these 

situations.

9.1.1. Precast Substructure Elements

The majority of the prefabricated substructures that are being 

detailed in the United States are precast concrete elements that 

are emulating cast-in-place structures. The design of these 

elements should follow the applicable LRFD provisions for cast-inplace and precast concrete construction.

The following are the minor modifications to the design of a 

precast concrete substructure that are required when using 

precast elements:

Design of the Grouted Splice Coupler

The AASHTO LRFD Bridge Design Specifications require 

that all mechanical reinforcing splice devices develop 

125% of the specified yield strength of the bar (Article 

5.11.5.2.2) [8]. Several manufacturers produce grouted 

splice couplers that can meet and exceed this requirement. 

If this requirement is met, the coupler can be treated the 

same as a reinforcing lap splice. 

The design of the elements is the same as the design of a 

standard reinforced concrete element with one minor 

change. The couplers are larger than the connecting bars; 

therefore in order to obtain proper cover over the coupler, 

the reinforcing cage needs to be moved toward the interior 

of the element. This may have an effect on the design of 

the element since the effective structural depth of the 

member is reduced when compared to cast-in-place 

concrete construction. The resulting change will be larger 

or more closely spaced bars.

Design of the Grouted Post-tensioning Duct Connections

The Texas DOT has completed research on the use of 

reinforcing dowels grouted into post-tensioning ducts for 

connections of pier bent caps. The research paper entitled

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“Development of a Precast Bent Cap System” [52] contains 

design criteria for this type of connection. The Washington 

State DOT has also completed significant research on 

these connections [54-56]. These research papers can be 

used for the design of these particular connections.

Design of Pile Connections for Precast Footings and Integral 

Abutment Bridges

The Iowa DOT has developed details for connections of 

precast elements to piles. These connections have been 

studied by Iowa State University and have been proven on 

actual projects. These details involve the use of corrugated 

steel pipes cast into the elements to form a void. The 

corrugations are used to transfer substructure loads into 

the piles via shear friction. The elements are simply 

placed over the piles and the voids are filled with concrete 

to make the connection. The research paper entitled 

“Precast Concrete Elements for Accelerated Bridge 

Construction” [12] contains design criteria for this and other 

connections. 

The corrugated pipes can also be used to reduce the 

shipping weight of elements. They can be filled with 

concrete after installation to make the element emulate a 

solid concrete structure. 

Design of Connections for Seismic Loading

Section 5.3.1.3 of this manual includes information on the 

design of prefabricated connections in seismic regions. 

The NCHRP report entitled “Development of Precast Bent 

Cap Systems for Seismic Regions” [11] contains design 

examples for seismic connections studied in the project. 

The Washington State DOT has also published papers on 

the design of connections for seismic loading [54-56].

9.1.2. Deck Panel Elements

The design of the reinforcing in the deck panels should follow the 

applicable provisions for concrete decks in the AASHTO LRFD 

Bridge Design Specifications [8]. Section 9.7.5 of the AASHTO 

Specifications has specific provisions for precast concrete decks. 

This includes requirements for grouted shear keys and 

longitudinal post-tensioning. Appendix A of the FHWA 

connections manual contains information on the design of the 

deck panel and the longitudinal post-tensioning [3].

The design of other deck systems is also covered in Chapter 9 of 

the AASHTO LRFD Bridge Design Specifications [8] including 

steel grid decks, wood decks and orthotropic decks.

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9.1.3. ABC Issues not Covered in the LRFD Bridge Design 

Specifications

Mechanical Reinforcing Splices in Seismic Connections 

The current AASHTO LRFD code does not allow the use of 

mechanical connectors in the plastic hinge zone of columns. 

Mechanical splices are required to be staggered a minimum of 24” 

for bridges in high seismic zones. (Section 5.10.11.4.1f [8]). 

The ACI Building Code Requirements for Structural Concrete [53] 

do allow mechanical connectors in the plastic hinge zone, 

provided that they can meet certain requirements. There are two 

levels of mechanical splice devices specified in the ACI 318 Code. 

Type 1 mechanical splices need to be capable of developing 

125% of the specified minimum yield strength of the bar. Type 2 

mechanical splices need to be capable of developing 100% of the 

specified minimum tensile strength of the bar (equal to 150% of 

specified yield for standard grade 60 Bars). 

The ACI 318 code has restrictions that are similar to the AASHTO 

Specifications for Type 1 mechanical splices; however the use of 

Type 2 mechanical splices are unrestricted for special moment 

frames constructed with precast concrete (including the plastic 

hinge zone). Upon further research and testing, provisions similar 

to the ACI code may eventually become part of the AASHTO 

LRFD Code.

Another approach that can be followed in most cases is to place 

the mechanical couplers in the footing and pier cap as opposed to 

the column hinge zones. The AASHTO provisions that restrict 

mechanical splices are for column reinforcing. There are no 

specific restrictions on footing and cap reinforcement. This is due 

to the lower demand that is placed on reinforcing outside of the 

column plastic hinge zone.

Innovative Full Depth Deck Panel Connections

With regard to transverse full depth deck panel connections, the 

AASHTO LRFD Bridge Design Specifications only contain 

provisions for longitudinal post-tensioning with grouted shear 

keys. Research has been completed on systems that do not have 

post-tensioning [36], and there are other states that have used 

reinforced concrete closure pours, and ultra-high performance 

concrete joints between panels. These systems may also be 

acceptable provided that that the details can emulate cast-in-place 

concrete or are supported by proper research efforts.

The AASHTO specifications should be amended to include other 

deck panel connections as research is completed. Designers may 

choose to use the research results for design at this time.

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Grouted Post-tensioning Duct Connections and Other Seismic 

Connections

Several research studies have investigated the use of corrugated 

metal post-tensioning duct for grouting of reinforcing bars and 

other seismic column connections [11, 52, and 54]. These 

connections are not currently covered in the AASHTO LRFD 

Bridge Design Specifications. The cited research reports do 

contain design guidance for these connections.

Shear capacity of Corrugated Metal Pipe Voids

Several states have used corrugated metal pipe voids to reduce 

element weight and to provide a connection [11,12]. These 

connections are primarily used to transmit direct shear and 

moment between two elements. The direct shear capacity of 

these connections is significant. Moment resistance can be 

accommodated through the use of reinforcing within the 

corrugated pipe void, or external to the void. The AASHTO LRFD 

Bridge Design Specifications do not specifically cover this type of 

connection. The provisions for interface shear in AASHTO Article 

5.8.4 are recommended for the calculation of the direct shear 

(shear friction) capacity of this type of connection. The provisions 

for “Normal concrete placed against a clean concrete surface, free 

of laitance, with a surface intentionally roughened to an amplitude

of 0.25 in.” are recommended. The corrugations of the pipe will 

act as a roughened surface, which justifies the use of this 

provision.

Dynamic Effects of Large Scale Bridge Moves

The AASHTO LRFD Bridge Design Specifications do not include 

provisions for the dynamic effects of large scale bridge moves. 

The Utah Department of Transportation has studied this by 

instrumenting many of the bridges that were moved. The results 

indicate that a conservative approximation of vertical dynamic 

effects is to increase the dead load of the structure by 15% for the 

analysis. The lateral effects of starting and stopping were not 

studied; however the effects on the bridge framing are thought to 

be negligible. The effects on the support framing are a different 

situation. Erection engineers should consult with heavy lift 

contractors regarding the level of lateral dynamic forces.

9.1.4. Design of Bridges with Large-scale Lifting Methods

The design of bridges built using large-scale prefabrication is not 

specifically covered in the AASHTO LRFD Bridge Design 

Specifications; however the tools required to design the bridge 

are. When lifting and moving a superstructure, the location of the 

support points as well as the stiffness of the supporting falsework 

need to be identified and accounted for in the design. 

Design-Build and CMGC Contracting Method

In a Design-Build or CMGC scenarios, the designers and the 

contractor are on the same team. The design of the bridge and 

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the falsework are under the direction of the project team. The 

stiffness of the falsework should be modeled with the bridge 

superstructure in order to account for the potential redistribution of 

loads due to deflection of the falsework. Hydraulic and shim 

systems can also be used to minimize this effect (see Section 

7.1). 

Design-Bid-Build

In the Design-Bid-Build contracting method, the contractor is not 

available during design development. This means that the exact 

makeup of the falsework is not known to the design engineer. In 

this case, there are two options available for the design of the 

bridge.

• Design the bridge with rigid supports: In this scenario, the 

support is assumed to be equal at each beam support 

point. This assumption must be clearly noted on the plans 

and in the specifications. The notes should indicate that 

equal support must be provided. Alternate support 

conditions (flexible falsework) can be allowed; however the 

contractor would be required to re-analyze the bridge and 

possible strengthen the members.

• Design and detail the falsework and large scale lifting 

machinery layout: This scenario is not common since 

design engineers typically are not experts in shoring 

design and large scale lifting systems. If this approach is 

taken, the designers should contact several heavy lift 

companies in order to determine which systems are 

feasible. 

Based on the above discussion, it can be seen that the DesignBuild or CMGC contracting method is best suited for a large-scale 

bridge prefabrication project. 

Recommended AASHTO LRFD Limit States

The following limit states checks are recommended during the 

design of the superstructure:

Strength Limit State:

Analyze and design the superstructure using all applicable 

Strength Limit States as specified in the AASHTO LRFD 

Bridge Design Specifications [8]. Include dynamic effects. 

Service Limit State:

Check the span for displacements and deck cracking 

based on 

Service I Limit State. Include dynamic effects. Check 

tension in the prestressed concrete superstructure using 

the Service III Limit State. Check crack control on 

prestressed concrete columns using the Service IV Limit 

State.

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9.2. LRFR Ratings

As with design, the rating procedures for prefabricated bridge systems 

typically follow traditional methods of analysis. This is due to the fact that 

most bridge elements built to date have followed the emulative detailing 

method. This means that the design and details emulate traditional 

design and construction. 

Analysis and rating of superstructures built with precast concrete decks 

should account for the transverse joints between the deck panels. If 

longitudinal post-tensioning is used, the tendons can be accounted for in 

the design of the negative moment regions of the girders.

9.3. Design and Analysis of Temporary Works

Temporary works such as shoring, earth retaining, support and bracing 

systems should be properly analyzed and designed in accordance with 

the applicable AASHTO Specifications [45,46] and general engineering 

principles. Refer to Chapter 7 for more information.

9.4. Evaluation of Existing Structures

If prefabricated elements will be transported to construction sites using 

hauling vehicles, all existing bridges and structures on the transport route 

should be evaluated for load carrying capacity. The AASHTO Manual for 

Bridge Evaluation [58] should be used. Special hauling permits may be 

required for movement of elements that are oversize and/or overweight. 

Designers should consult with local and state authorities on permitting 

requirements.

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References

1. Decision-Making Framework for Prefabricated Bridge Elements and Systems (PBES),

U.S. Department of Transportation, Federal Highway Administration, Publication 

Number FHWA-HIF-06-030, May 2006

2. Manual on the Use of Self-Propelled Modular Transporters to Remove and Replace 

Bridges, U.S. Department of Transportation, Federal Highway Administration, 

Publication Number FHWA-HIF-07-022, June 2007

3. Connection Details for Prefabricated Bridge Elements and Systems, U.S. Department 

of Transportation, Federal Highway Administration, Publication Number FHWA-IF-09-

010, March 2009

4. Road User Cost Manual, The New Jersey Department of Transportation, June 2001

5. Geotechnical Engineering Circular (GEC) No. 8, Design and Construction Of 

Continuous Flight Auger Piles, U.S. Department of Transportation, Federal Highway 

Administration, Publication Number FHWA-HIF-07-039, April 2007.

6. Emulating Cast-in-Place Detailing in Precast Concrete Structures ACI-550.1 R01,

The American Concrete Institute, 2001

7. SPMT Process Manual And Design Guide, The Utah Department of Transportation, 

November 2009.

8. AASHTO LRFD Bridge Design Specifications, American Association of State Highway 

and Transportation Officials, Washington, D.C., Fourth Edition 2007.

9. Badie and Tadros “Full Depth Precast Concrete Bridge Deck Panel Systems” Report 

Number 584, National Cooperative Highway Research Program, Transportation 

Research Board, 2008

10. Public Involvement Techniques for Transportation Decision-making, U.S. 

Department of Transportation, Federal Highway Administration, Publication Number 

FHWA-PD-96-031, December 1996

11. Restrepo, Tobolski, Matsumoto, Development of a Precast Bent Cap System for 

Seismic Regions Report Number 681, National Cooperative Highway Research 

Program, Transportation Research Board, 2011

12. Wipf, Klaiber, and Hockerman, Precast Concrete Elements for Accelerated Bridge 

Construction, IHRB Project TR-561, Iowa Highway Research Board and the Iowa 

Department of Transportation, January 2009

13. Caner and Zia, Behavior and Design of Link Slabs for Jointless Bridge Decks, 

Journal of the Precast Prestressed Concrete Institute, May-June 1998

14. Aktan, Attanayake, and Ulku, Combining Link Slab, Deck Sliding over Backwall, 

and Revising Bearings, Research Report RC-1514, Western Michigan University 

and the Michigan Department of Transportation, 2008

15. ASTM A955 - 10a Standard Specification for Deformed and Plain Stainless-Steel 

Bars for Concrete Reinforcement, ASTM International, West Conshohocken, PA

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Federal Highway Administration Accelerated Bridge Construction Manual 

16. ASTM A1035 - 09 Standard Specification for Deformed and Plain, Low-carbon, 

Chromium, Steel Bars for Concrete Reinforcement, ASTM International, West 

Conshohocken, PA

17. Merrill, “Texas’ Use of Precast Concrete Stay-in-Place Forms for Bridge Decks”, 

2002 Concrete Bridge Conference, 

18. Jones, Furr, “A Study of Prestressed Panels and Composite Action in Concrete 

bridges Made of Prestressed Beams, Prestressed Sub-Deck Panels, and Cast-inplace Deck”, Research Project No. 2-5-70-145, Texas Highway Department

19. Bieschke and Klingner, “The Effects of Transverse Strand Extensions on the 

Behavior of Precast Prestressed Panel Bridges”, Research Report 303-1F, Center 

for Transportation Research, The University of Texas at Austin, June 1982

20. “Full Depth Precast Concrete Deck Slabs”, PCINER-02-FDPCDS, Precast 

Prestressed Concrete Institute, Northeast Bridge Technical Committee, June 2002.

21. Abendroth, "Nominal Strength of Composite Prestressed Concrete Bridge Deck 

Panels," Journal of Structural Engineering, ASCE, Vol. 121, No. 2, February 1995, 

pp. 307-318

22. Babaei, Fouladgar, and Nicholson, “Nighttime Bridge Deck Replacement with Full 

Depth Precast Concrete Panels at Route 7 over Route 50, Fairfax County, Virginia,”

Transportation Research Board, 80th Annual Meeting, January 7-11, 2001, Paper 

#01-0196, Washington, D.C.

23. Badie, Baishya, and Tadros, “NUDECK- An Efficient and Economical Precast Bridge 

Deck System”, Prestressed/Precast Concrete Institute (PCI) Journal, SeptemberOctober, Vol. 43, No. 5, 1998, pp. 56-74.

24. Badie, Baishya, and Tadros,“NUDECK- An Efficient and Economical Precast 

Bridge Deck System”, Prestressed/Precast Concrete Institute (PCI) Journal, 

September-October, Vol. 43, No. 5, 1998, pp. 56-74.

25. Badie, Tadros, Kakish, Splittgerber, and Baishya, “Large Studs for Composite Action 

in Steel Bridge Girders,” American Society of Civil Engineering (ASCE), Bridge 

Journal, Vol. 7, No. 3, May/June 2002, pp. 195-203.

26. Biswas, "Precast Bridge Deck Design Systems," PCI Journal, V. 31, No. 2, MarchApril 1986, pp. 40-94.

27. Culmo, "Bridge Deck Rehabilitation Using Precast Concrete Slabs," Paper Number 

IBC-91-55, Eighth Annual International Bridge Conference, Pittsburgh, 

Pennsylvania, June 10-12, 1991.

28. Issa, Idriss, Kaspar, and Khayyat,"Full Depth Precast and Precast, Prestressed 

Concrete Bridge Deck Panels," PCI Journal, Vol. 40, No. 1, January-February 

1995a, pp. 59-80.

29. Issa, Yousif, Issa, Kaspar and Khayyat, "Field Performance of Full Depth Precast 

Panels in Bridge Deck Reconstruction," PCI Journal, Vol. 40, No. 3, May-June 

1995d, pp. 82-108.

30. Issa, Yousif, Issa, Kaspar, and Khayyat, "Analysis of Full Depth Precast Concrete 

Bridge Deck Panels," PCI Journal, Vol. 43, No. 1, January-February 1998, pp. 74-

85.

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Federal Highway Administration Accelerated Bridge Construction Manual 

31. Issa, Anderson, Domagalski, and Khayyat, “Design Considerations of Full Depth 

Precast/Prestressed Concrete Bridge Deck Panels,” Proceedings of the 1st annual 

Concrete Bridge Conference, October 6-9, 2002, p 20.

32. Issa, Patton, Thomas, Abdalla, Hiba, Yousif, Alfred, and Issa, "Composite Behavior 

of Shear Connections in Full-Depth Precast Concrete Bridge Deck Panels on Steel 

Stringers," PCI Journal, September/October 2003, vol. 48, no. 5, pp. 76-89.

33. Menkulasi and Roberts-Wollmann, “Behavior of Horizontal Shear Connections for 

Full-Depth Precast Concrete Bridge Decks on Prestressed I-Girders,” PCI Journal, V. 

50, No. 3., May/June 2005, pp. 60-73.

34. Scholz, Wallenfelsz, Cintia, Roberts-Wollmann, “Recommendations for the 

Connection Between Full Depth Precast Bridge Deck Panel Systems and Precast IBeams”, Final Report Number VTRC 07-CR17, Virginia Transportation Research 

Council, Charlottesville, VA

35. Tadros, Badie, and Kamel, "A New Connection Method for Rapid Removal of Bridge 

Decks," PCI Journal, May-June 2002, Vol. 47, No. 3, pp. 2-12.

36. Tadros, and Baishya, "Rapid Replacement of Bridge Decks," Final Report, 12-41, 

National Cooperative Highway Research Program, Transportation Research Board, 

July 1997.

37. Tadros, and Baishya, “Rapid Replacement of Bridge Decks,” National Cooperative 

Highway Research Program, NCHRP Report 407, Washington, D.C., 1998.

38. Lutz and Scalia, "Deck Widening and Replacement of Woodrow Wilson Memorial 

Bridge" PCI Journal, V. 29, No. 3, May-June, 1984, pp. 74-93.

39. Caccese and Yorulmaz, “Laser Welded Steel Sandwich Panel Bridge Deck 

Development: Finite Element Analysis and Stake Weld Strength Tests”, Report 

Number 09-09, Maine Department of Transportation Research Division, September 

2009. 

40. Azizinamini, Yakel, and Farimani, Development of a Steel Bridge System – Simple 

for Dead Load and Continuous for Live Load, Volumes 1 and 2, National Bridge 

Research Organizartion and the Nebraska Department of Roads, 2005

41. ASTM C1577 Precast Reinforced Concrete Monolithic Box Sections for Culverts, 

Storm Drains, and Sewers Designed According to AASHTO LRFD, ASTM 

International, West Conshohocken, PA

42. McLean and Smith, Noncontact Lap Splices in Bridge Column-Shaft Connections, 

Washington State Transportation Center (TRAC) and the Washington State 

Department of Transportation, Report Number WA-RD 417.1, July 1997

43. Sprinkel, Very-Early-Strength Latex Modified Concrete Overlay, Virginia 

Transportation Research Council, Technical Assistance Report Number TAR 99-

TAR3, December 1998

44. Ross, Sickling, Zimmer, and Michie, “Recommended Procedure for the Safety 

Performance Evaluation of Highway Features,” National Cooperative Highway 

Research Program, NCHRP Report 350, Washington, D.C., 1993.

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Federal Highway Administration Accelerated Bridge Construction Manual 

45. AASHTO Guide Specifications for Bridge Temporary Works, American Association of 

State Highway and Transportation Officials, Washington, D.C., First Edition 1995 with 

2008 Interim Revisions.

46. AASHTO Construction Handbook for Bridge Temporary Works, American Association 

of State Highway and Transportation Officials, Washington, D.C., First Edition 1995 

with 2008 Interim Revisions.

47. PCI Design Handbook Precast and Prestressed Concrete, The Precast Prestressed 

Concrete Institute, Chicago, IL, Seventh Edition

48. Post-Tensioning Tendon Installation and Grouting Manual, U.S. Department of 

Transportation, Federal Highway Administration, May 2004

49. Qiao, McLean, and Zhuang, Mitigation Strategies for Early-Age Shrinkage Cracking 

in Bridge Decks, Report Number WA-RD 747.1, Washington State Department of 

Transportation and Washington State University, April 2010

50. AASHTO T334-08 Practice for Estimating the Crack Tendency of Concrete, 

AASHTO Standard Specifications for Transportation Materials and Methods of 

Sampling and Testing (29th Edition) and AASHTO Provisional Standards, 2009 

Edition 

51. Tests on Re-Bar Splices in Reinforced Concrete Columns using NMB Splice Sleeves, 

Report Number NPD-024, Splice Sleeve Japan, LTD. (available from Splice Sleeve 

North America, Inc.)

52. Matsumoto, Waggoner, Sumen, Kreger, Wood, and Breen, “Development of a 

Precast Bent Cap System”, Center for Transportation Research, The University of 

Texas at Austin, January 2001

53. Building Code Requirements for Structural Concrete (ACI 318-08), American 

Concrete Institute Committee 318, 2008. 

54. Wacker, Hieber, Stanton, Eberhard, Design of Precast Concrete Piers for Rapid 

Bridge Construction in Seismic Regions, Washington State Transportation Center 

(TRAC) and the Washington State Department of Transportation, Report Number 

WA-RD 629.1, August 2005

55. Steuck, Pang, Stanton, Eberhard, Anchorage of Large-Diameter Reinforcing Bars 

Grouted into Ducts, Washington State Transportation Center (TRAC) and the 

Washington State Department of Transportation, Report Number WA-RD 684.1, 

November 2007

56. Pang, Steuck, Cohagen, Stanton, Eberhard, Rapidly Constructible Large-bar 

Precast Bridge Bent Seismic Connection, Washington State Transportation Center 

(TRAC) and the Washington State Department of Transportation, Report Number 

WA-RD 684.2, October 2008

57. Highway Capacity Manual 2010, Transportation Research Board, 2010

58. AASHTO Manual for Bridge Evaluation, American Association of State Highway 

and Transportation Officials, Washington, D.C., Second Edition 2010

59. AASHTO Specification MP 18M/MP 18-09 Uncoated, Corrosion-Resistant, 

Deformed and Plain Alloy, Billet-Steel Bars for Concrete Reinforcement and 

Dowels, American Association of State Highway and Transportation Officials, 

Washington, D.C.,

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Federal Highway Administration Accelerated Bridge Construction Manual 

60. Shahrooz, Miller, Harries, and Russell, Design of Concrete Structures using HighStrength Steel Reinforcement, National Cooperative Highway Research Program, 

NCHRP Report 679, Washington, D.C., 2011 

61. LaViolette, Wipf, Lee, Bigelow and Phares, Bridge Construction Practices using 

Incremental Launching, National Cooperative Highway Research Program, NCHRP 

Project 20-07, Task 229, Transportation Research, Washington, D.C., 2007

62. Mallela, Huie, Lord and Sadasivam, Return on Investment from Deploying Project 

Delivery Innovations: Methodology and Findings from the Highways for Life 

Program, 2nd International Conference on Transportation Construction 

Management, Orlando, FL, 2011

63. Littleton, Mallela and Hoffman, Iowa Demonstration Project: Improvements to the 

24th Street–I-29/80 Interchange in Council Bluffs, HfL Demonstration Project 

Report, Office of Infrastructure, Federal Highway Administration, Washington, DC, 

2009.

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Appendices

Appendix A: Design Examples

As stated in Chapter 9, the design of most ABC elements and systems follows 

traditional AASHTO LRFD design specifications. Emulation detailing is common. 

The goal of emulation detailing is to mimic a cast-in-place reinforced concrete 

structure using precast concrete elements. Most ABC projects in the United 

States are based on this concept. 

The following sections contain information on the most common prefabricated 

elements currently in use:

Example A1.1: Full-depth Precast Concrete Deck Panels

Figure A1.1-1 is a sketch of a typical precast concrete deck panel installation. 

The FHWA Connections manual [3] contains design information of this type of 

element including an example of the design of the post-tensioning system.

Figure A1.1-1 Typical Precast Concrete Deck Panel Installation

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Example A1.2: Precast Concrete Piers

Emulative detailing is typically used for piers. The design of the pier elements is 

accomplished using the LRFD specifications. The only change with respect to 

ABC is the design of the connections between the elements. Again, emulation is 

used to obtain the desired performance.

Figure A1.2-1 shows a transparent view of a wall pier. The pier includes precast 

concrete footings supported on piles, precast wall stems, and precast caps. 

Corrugated pipe voids are used to make connections and to reduce member 

weight. Closure pours are used to make the footings continuous. Note that this 

example is similar to an open frame pier bent and a cantilever abutment or 

retaining wall.

Figure A1.2-1 Precast Pier Supported on Piles

The pile design would follow normal practice. The connection of the pile to the 

footings is made within a corrugated pipe void. The research entitled “Precast 

Concrete Elements for Accelerated Bridge Construction” [15] can be used to 

check the connection for punching shear. The AASHTO provisions for interface 

shear can also be used.

The design of the pier footing is based on the LRFD specifications assuming 

cast-in-place concrete. The spacing of the footing reinforcement needs to be 

adjusted to account for the size of the corrugated pipe voids. It is possible to 

keep uniform reinforcing spacing by running the reinforcement through the voids. 

This is discouraged due to the added complexity in fabrication. Continuity of the 

footing can be made with small closure pours between the footings. These 

closure pours would be completed after the placement of the wall stems. 

The design of the wall stems would be based on the LRFD specifications 

assuming cast-in-place concrete. The connection between the wall stem and the 

footing can be made with mechanical splice couplers. Mechanical couplers 

meeting the requirements of the LRFD specifications can be used to substitute 

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for a lap splice. If grouted post-tensioning ducts are used, the research paper 

entitled “Development of a Precast Bent Cap System” [56] can be used to design 

the grouted duct connection. The joints between the wall stem elements can be 

treated as typical wall expansion joints, therefore a structural connection is not 

required. Some designers have designed these joints with a grouted shear key. 

Corrugated pipe voids are used to reduce the member weight and to assist with 

the cap connection. These voids would be filled with concrete after installation of 

the wall stems.

The design of the pier cap is also based on the LRFD specifications assuming 

cast-in-place concrete. This is a low moment demand element since there is no 

spacing between wall stems. The connection between the wall elements and the 

cap can be made within the corrugated pipe voids. Projecting reinforcement can 

be placed within the void pour during the installation of the wall elements. This 

reinforcement can be designed to resist the moment demand at the joint. Once 

the cap is set on top of the wall elements, the voids in the cap can be grouted or 

concreted through ports to complete the connection.

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Example A1.3: Precast Integral Abutments

Emulative detailing is also used for integral abutments. State bridge design 

manuals and specifications should be reviewed since the LRFD specifications do 

not cover integral abutment designs in great detail. The AASHTO LRFD 

specifications can be used for the design of the internal reinforcement. 

Figure A1.3-1 shows a sketch of a precast concrete integral abutment prior to 

placement of the superstructure. Figure A1.3-2 is a typical section of a Utah 

DOT Integral abutment. The abutment includes precast wall stems supported on 

piles, precast wingwalls, and precast backwall stems. Corrugated pipe voids are 

used to make connections to the piles and to reduce member weight. Closure 

pours are used to make the integral connection to the superstructure. The Utah 

details show a separate precast backwall element connected with grouted splice 

sleeve connectors. The backwall can also be fabricated integral with the 

abutment cap as shown in the sketch. 

Figure A1.3-1 Precast Integral Abutment

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The connection of the pile to the abutment cap is made with a corrugated 

pipe void. The research entitled “Precast Concrete Elements for 

Accelerated Bridge Construction” [15] can be used to check the 

connection for punching shear. The AASHTO provisions for interface 

shear can also be used.

The joints between the abutment cap elements are simple grouted shear 

keys. This is somewhat different than conventional cast-in-place concrete 

integral abutments, where the cap is cast continuous across the width of 

the abutment. Maine DOT used match-cast stem elements combined 

with transverse post-tensioning. This is a good connection, but it may be 

a somewhat slower construction process. The concept behind the 

grouted key is to design the abutment stem with one-way action. The 

primary reinforcement would be run vertically from the superstructure 

pour to the abutment stem. The transverse reinforcement would run 

across the pile voids and terminate at the joints. This reinforcement 

Figure A1.3-2 Typical Section Through Abutment

(source: Utah DOT Standards) 

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would be designed assuming that the joint was a simple pin connection. 

The integral pour between the beams will further join the stem elements.

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Example A1.4: Erection Calculations for a Full Depth Precast Concrete Deck Panel

The goal is to lift, transport and handle the panel without causing cracking. Chapter 5 of 

the PCI Design Handbook [47] offers information on the design of panels for lifting and 

handling. Normally, this calculation would be completed by the contractor. The intent is 

to present a sample calculation to designers who may review calculations and 

contractors that may be designing for lifting. Agencies and designers may specify other 

more stringent handling requirements that designers and contractors should be aware of 

prior to designing lifting and handling systems.

This example is for a hypothetical deck panel. It will be checked for handling and 

shipping according to Chapter 5 of the PCI Design Handbook based on “no cracking 

criteria”. Article and table references in this example refer to the PCI Design Handbook.

Panel information: (refer to Figure A1.4-1 on next page for reference)

1. Panel Overall dimensions

a. Length: b = 24 feet

b. Width: a = 8 feet

c. Thickness: t = 8”

d. Void size: 16” x 5”

2. Concrete Information:

a. Compressive strength at removal from forms: 2000psi

b. Compressive strength at delivery: 4000psi

c. Unit weight: 150 pcf (including reinforcing)

3. Internal reinforcing (all Grade 60 mild reinforcing)

a. Longitudinal bars: #5@6” top and bottom

b. Transverse bars: #4@12” top and bottom

c. Top cover: 21⁄2”

d. Bottom Cover: 11⁄2”

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Step 1: Calculate Member weight

Volume of concrete = 8’ x 24’ x 0.666’ = 128 cf (neglect voids)

Weight of panel = 128 cf x 0.150 k/cf = 19.2 kips

Step 2: Calculate Allowable Stresses (Article 5.3.3.2)

For members designed for a “no cracking” approach, use an allowable stress 

equal to the modulus of rupture divided by a factor of safety of 1.5. It should be 

noted that this approach does not guarantee a crack free section. Experience 

has shown that decks designed to these provisions have performed well.

Allowable stress at removal from forms = 7.5 √f’ci / 1.5 = 5 √2000 = 224 psi

Allowable stress for shipping = 7.5 √f’c / 1.5 = 5 √4000 = 316 psi

Step 3: Determine Equivalent Static Load Multipliers (Table 5.3.3.1)

Form Stripping: 1.3 (smooth mold with no false joints or reveals)

Yard handling: 1.2

Travel: 1.5

Step 4: Calculate Section Properties for Critical Sections (refer to diagram)

Section resisting Mx: 

Overall Width = 15t = 15 x 8 = 120 in

 or = b/2 = 240 / 2 = 120 in  control

Net Width (minus 1 void) = 120” – 16” = 104”

Sx = w t2 / 6 = 104 x 82 / 6 = 1109 in3

Section resisting My: 

Overall Width = a / 2 = 96 / 2 = 48 in 

Net Width (minus 2 voids) = 48” – (2 x 5”) = 38”

Sy = w t2 / 6 = 38 x 82 / 6 = 405 in3

Step 5: Check Form Stripping (Figure 5.3.1.2 moments with 1.3 form stripping factor)

+Mx = -Mx = 0.0107wa2b x 1.3 

+My = -My = 0.0107wab2 x 1.3 

w = weight per unit area = 0.666’ x .150 k/cf = 0.100 ksf

a = 8’ b = 24’ 

Transverse Bending:

Mx = 0.0107 x 0.100ksf x (8ft)2 x 24ft x 12(in/ft) x 1.3 = 25.64 k-in

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ft = fb = Mx/Sx = 25.64 / 1109 = 0.023 ksi < 0.224 ksi allowable OK

Longitudinal Bending:

My = 0.0107 x 0.100ksf x 8ft x (24ft)2 x 12(in/ft) x 1.3 = 76.92 k-in

ft = fb = Mx/Sx = 76.92 / 405 = 0.190 ksi < 0.224 ksi allowable OK

Step 6: Check Shipping and Handling (Figure 5.3.1.2 moments with 1.5 travel factor)

+Mx = -Mx = 0.0107wa2b x 1.5 

+My = -My = 0.0107wab2 x 1.5 

w = weight per unit area = 0.666’ x .150 k/cf = 0.100 ksf

a = 8’ b = 24’ 

Transverse Bending:

Mx = 0.0107 x 0.100ksf x (8ft)2 x 24ft x 12(in/ft) x 1.5 = 29.58 k-in

ft = fb = Mx/Sx = 29.58 / 1109 = 0.027 ksi < 0.316 ksi allowable OK

Longitudinal Bending:

My = 0.0107 x 0.100 x 8 x 242 x 12 x 1.5 = 88.75 k-in

ft = fb = Mx/Sx = 88.75 / 405 = 0.219 ksi < 0.316 ksi allowable OK

Step 7: Calculate Lifting Hardware Loads

Load per anchor = total weight / 4 = 19.2k / 4 = 4.8 kips

Form stripping load = 4.8 x 1.3 = 6.24 kips (f’ci = 2000psi)

Handling load = 4.8 x 1.5 = 7.2 kips (f’c = 4000psi)

Design lifting inserts for the following:

Use embedded inserts and erection devices with a pullout strength at 

least equal to 4 times the calculated loads on the device (Article 5.3.3.2).

The calculated loads are for vertical lifting. Account for angular load 

vectors in the embedded insert design.

Step 8: Check Member Strength at Form Stripping

Negative bending controls due to larger top cover (smallest d)

Assume: Singly reinforced section (conservative)

Transverse Bending

Mx = 25.64 k-in (unfactored)

Factored Mx = 25.64 x 1.25 = 32.05 k-in

Beam information

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Width = 120 in

Reinforcing = 10 x 0.2 in2 = 2.0 in2

 (#4 @ 12”)

d = 8in – 2.5in (cover) – 0.625in (top bar) – 0.5in/2 (trans. bar)

 = 4.625 in

f’ci = 2000psi fy = 60,000 psi

β1 = 0.85 (for f’ci = 2000 psi) 

T = AsFy = 2.0 in2 x 60 ksi = 120 kips

a = T / (0.85 x f’ci x b) = 120kips / (0.85 x 2ksi x 120 in) = 0.68 in

Tension control check

Distance to neutral axis = c = a/ β1 = 0.68in / 0.85 = 0.80 in

Steel Strain = 0.003 x (d-c)/c = 0.003 x (4.625in – 0.80 in)/0.80 in

 = 0.0144

Yield Strain = Fy/Es = 60ksi / 29,000 ksi = 0.0021

Steel strain is greater than yield strain therefore tension controls 

Calculate Φ (AASHTO LRFD Article 5.5.4.2.1)

Steel strain is greater than 0.005, therefore Φ = 0.9

ΦMn = Φ AsFy (d – a/2) = 0.9 x 120 kips (4.625in – 0.68in/2)

= 463 k-in >> 32.05 k-in OK

Longitudinal Bending:

My = 76.92 k-in (unfactored)

Factored Mx = 76.92 x 1.25 = 96.15 k-in

Beam information

Width = 38 in

Reinforcing = 9 x 0.31 in2 = 2.79 in2

d = 8” – 2.5” (cover) – 0.625”/2 (top bar)

 = 5.19 in

f’ci = 2000psi fy = 60,000 psi

β1 = 0.85 (for f’ci = 2000 psi) 

T = AsFy = 2.79 in2 x 60 ksi = 167.4 kips

a = T / (0.85 x f’ci x b) = 167.4kips / (0.85 x 2ksi x 38 in) = 2.59 in

Tension control check

Distance to neutral axis = c = a/ β1 = 2.59in / 0.85 = 3.05 in

Steel Strain = 0.003 x (d-c)/c = 0.003 x (5.19in – 3.05 in)/3.05 in

 = 0.0021

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Federal Highway Administration Accelerated Bridge Construction Manual 

Yield Strain = Fy/Es = 60ksi / 29,000 ksi = 0.0021

Steel strain is equal to yield strain therefore tension controls 

Calculate Φ (AASHTO LRFD Article 5.5.4.2.1)

Steel strain is less than 0.005 and greater than 0.002

therefore Φ = 0.65 + 0.15(d/c – 1) (AASHTO LRFD Fig. C5.5.4.2.1-1)

Φ = 0.65 + 0.15(5.19in / 3.05in – 1) = 0.755

ΦMn = Φ AsFy (d – a/2) = 0.755 x 167.4 kips (5.19in – 2.59in/2)

 = 492 k-in >> 96.15 k-in OK 

By inspection, shipping moments will be OK.

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Example A1.5: Reference Documents that Include Design Information

Many of the reference documents in this manual include design information. The 

following is a list of the references and the design information contained in each:

Table A1.5-1 Reference Documents that Include Design Information

Reference 

Number

See Pages 

269-273

Reference Titles Design Information

2 Manual on the Use of SelfPropelled Modular Transporters to 

Remove and Replace Bridges

Design of bridges with 

SPMT installation.

Design of shoring systems 

3 Connection Details for Prefabricated 

Bridge Elements and Systems

Design of connections

Design of longitudinal posttensioning in precast decks

6 Emulating Cast-in-Place Detailing in 

Precast Concrete Structures

Emulative detailing of 

precast connections

7 SPMT Process Manual and Design 

Guide

Design of bridges with 

SPMT installation.

Design of shoring systems

9, 20-38 Various research reports covering 

full depth precast concrete deck 

panels

Design of Precast Deck 

Panels

Design of Connections to 

girders

Design of connections 

between panels

11 Development of Precast Bent Cap 

Systems for Seismic Regions

Design of column to cap 

connections for pier bents in 

seismic regions

12 Precast Concrete Elements for 

Accelerated Bridge Construction

Design of corrugated pipe 

void connections

13, 14 Behavior and Design of Link Slabs 

for Jointless Bridge Decks

Combining Link Slab, Deck Sliding 

over Backwall, and Revising 

Bearings

Design of Link slab 

connections

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Federal Highway Administration Accelerated Bridge Construction Manual 

Reference 

Number

See Pages 

269-273

Reference Titles Design Information

17-19 Use of Precast Concrete Stay-inPlace Forms for Bridge Decks

A Study of Prestressed Panels and 

Composite Action in Concrete 

bridges Made of Prestressed 

Beams, Prestressed Sub-Deck 

Panels, and Cast-in-place Deck

The Effects of Transverse Strand 

Extensions on the Behavior of 

Precast Prestressed Panel Bridges

Design of partial depth 

precast deck panels

42 Noncontact Lap Splices in Bridge 

Column-Shaft Connections

Design of a connection 

between a large diameter 

drilled shaft and a precast 

concrete column

47 PCI Design Handbook Precast and 

Prestressed Concrete

Design of precast products 

for lifting and handling

48 Post-Tensioning Tendon Installation 

and Grouting Manual

Design and specifications 

for installation of posttensioning systems

51 Tests on Re-Bar Splices in 

Reinforced Concrete Columns using 

NMB Splice Sleeves

Structural performance of 

grouted splice sleeve 

couplers

52, 54-56 Development of a Precast Bent Cap 

System 

Design of Precast Concrete Piers 

for Rapid Bridge Construction in 

Seismic Regions

Anchorage of Large-Diameter 

Reinforcing Bars Grouted into 

Ducts

Rapidly Constructible Large-bar 

Precast Bridge Bent Seismic 

Connection

Design of pier bent cap 

connections using grouted 

post-tensioning ducts.

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Federal Highway Administration Accelerated Bridge Construction Manual 

Appendix B: Standard and Proprietary Products

The following are products used in ABC/PBES projects that are potentially proprietary 

items. 

Prefabricated Superstructure Systems

EffideckTM

BEBO® Concrete Arch System

HY-SPAN® Bridge System

Grouted Reinforcing Splice Couplers

NMB Splice Sleeve

Dayton Superior DB Grout Sleeve

Erico Lenton Interlok Rebar Splicing System 

Proprietary Retaining Wall Systems

Reinforced Earth® and Retained EarthTM Retaining Walls

Doublewal Retaining Wall

T-WALL® Retaining Wall System

Post-tensioning Systems

Dydiwag Systems

VSL Post-tensioning Systems

Williams Threadbar Systems

FHWA has rules and regulations concerning the use and specification of Proprietary 

Products on Federal-aid highway projects. The FHWA has a website that is devoted to 

this subject. It can be found at: www.fhwa.dot.gov/construction/cqit/propriet.cfm

The listing of the products above does not constitute approval for these products for 

usage on Federal-aid projects.

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Appendix C: Sample Construction Specifications

The FHWA Manual entitled “Connection Details for Prefabricated Bridge 

Elements and Systems” [3] contains sample specifications from ABC projects 

(Appendix C). Since the publication of the manual, Several States have 

developed ABC specifications. 

The following is a listing of these specifications from several state agencies. 

These specifications are written in the format of the particular agency; therefore 

the formats are not similar. These specifications are presented for reference only

and may become outdated as time passes. Designers can use the information 

contained in this appendix; however the specifications should be carefully 

reviewed and modified as needed.

Example Title Page

1 Utah DOT – Precast Substructure Elements 292

2 Utah DOT – Precast Concrete Deck Panel

3 Utah DOT – Bridge Construction using Self-propelled 

Modular Transporters (SPMT)

312

4 Utah DOT – Structural Lightweight Concrete

 (used for reducing element weight)

327

5 Massachusetts DOT – High Early Strength Concrete 

 (used for closure pours)

342

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Example Specification C1:

Source: Utah Department of Transportation

Title: Precast Substructure Elements 

Use: Covers precast abutments, piers, and walls

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May 24, 2010

SPECIAL PROVISION

PROJECT #

PIN #

SECTION 03131S

PRECAST SUBSTRUCTURE ELEMENTS

Add Section 03131:

PART 1 GENERAL 

1.1 SECTION INCLUDES

A. This work consists of furnishing, erecting, and installing all precast 

concrete elements for bridge substructures including all necessary 

materials and equipment to complete the work as shown on the 

plans. Substructures in general include footings, columns, pier 

caps, abutment stems, and wall stems. The use of cast-in-place 

concrete will not be considered for substitution.

B. Procedures for installing elements

C. Procedures for placing structural non-shrink grout.

D. Procedures for placing flowable bedding concrete.

E. Procedures for placing high early strength concrete at closure 

pours.

1.2 RELATED SECTIONS

A. Section 03055: Portland Cement Concrete

B. Section 03211: Reinforcing Steel and Welded Wire

C. Section 03310: Structural Concrete

D. Section 03575: Flowable Fill

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1.3 REFERENCES

A. AASHTO M 36: Corrugated Steel Pipe, Metallic-Coated, for 

Sewers and Drains

B. AASHTO M 245: Standard Specification for Corrugated Steel Pipe, 

Polymer-Precoated, for Sewers and Drains

C. AASHTO T 106: Standard Test Method for Compressive Strength 

of Hydraulic Cement Mortars (Using 2-in. Cube Specimens)

D. AASHTO T 160: Standard Method of Test for Length Change of 

Hardened Hydraulic Cement Mortar and Concrete

E. AASHTO T 161: Standard Method of Test for Resistance of 

Concrete to Rapid Freezing and Thawing

F. AASHTO T 260: Standard Method of Test for Sampling and 

Testing Chloride Ion in Concrete and Concrete Raw Materials

G. AASHTO Standard Specifications for Highway Bridges

H. ASTM A 370: Standard Test Methods and Definitions for 

Mechanical Testing of Steel Products

I. ASTM A 615: Standard Specification for Deformed and Plain 

Carbon-Steel Bars for Concrete Reinforcement.

J. ASTM A 706: Standard Specification for Low-Alloy Steel Deformed 

and Plain Bars for Concrete Reinforcement. 

K. ASTM C 666: Standard Test Method for Resistance of Concrete to 

Rapid Freezing and Thawing

L. ASTM C 882: Standard Test Method for Bond Strength of EpoxyResin Systems Used With Concrete By Slant Shear.

M. ASTM D 2240: Standard Test Method for Rubber Property – 

Durometer Hardness

N. PCI Design Handbook, Fifth Edition with all Interims and Errata

O. UDOT Quality Management Plan

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1.4 DEFINITIONS

A. Continuous Butt Welded Hoops: Individual reinforcing steel bars 

that are formed into a circular shape with ends connected by a 

resistance butt welding process.

1. The hoops are used to provide transverse column reinforcing 

by confining the vertical column reinforcing.

B. Grouted Splice Coupler: Mechanical devices used to splice 

reinforcing steel within precast concrete elements. 

1. These couplers are proprietary devices that are comprised of 

a combination of a steel casting and a high strength 

cementitious grout.

2. Some couplers combine a threaded connection for the bar 

that is cast into the element combined with a grouted portion 

that is used to make the connection in the field.

3. The grout used for the coupler is part of the proprietary 

system and is supplied by the coupler manufacturer.

1.5 SUBMITTALS

A. The submittals requiring written approval from the Engineer are as 

follows:

1. Assembly Plan:

a. Submit five sets of half-size, 11 x 17 inch sheets with 

a 11⁄2 inch blank margin on the left-hand edge.

b. Place the project designation data in the lower righthand corner of each sheet.

c. Follow Chapter 5 of the PCI Design Handbook for 

handling and erection bracing requirements.

d. Comply with all requirements of applicable 

environmental permits.

e. Comply with the construction timeframes specified in 

the Maintenance of Traffic Specifications.

f. Include a work area plan, depicting items such as 

utilities overhead and below the work area, drainage 

inlet structures, and protective measures.

g. Include details of all equipment that will be employed 

for the assembly of the substructure.

h. Include details of all equipment to be used to lift 

substructure elements including cranes, excavators, 

lifting slings, sling hooks, and jacks. Include crane 

locations, operation radii, and lifting calculations.

i. Include a detailed sequence of construction and a

timeline for all operations. Account for setting and 

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cure time for grouts, grouted splice couplers, and 

concrete closure pours.

j. Include methods of providing temporary support of the 

elements. Include methods of adjusting and securing 

the element after placement.

k. Include procedures for controlling tolerance limits both 

horizontal and vertical. Include details of any 

alignment jigs including bi-level templates for 

reinforcing anchor dowels.

l. Include a detailed installation procedure for 

connecting the grouted splice couplers including pregrout and post-grout applications. 

m. Include methods for curing grout and closure pour 

concrete.

n. Include proposed methods for installing non-shrink 

grout and the sequence and equipment for the 

grouting operation.

o. Include methods for placement of flowable bedding 

concrete for spread footings. Add grout ports in the 

footings to facilitate the bedding process if required.

p. Include methods of forming closure pours including 

the use of backer rods. Do not assume that the 

backer rods will restrain the pressure from the grout in 

vertical grout joints. Provide additional forming to 

retain the backer rod.

q. Include a list of personnel that will be responsible for 

the grouting of the reinforcing splice couplers. Include 

proof of completion of two successful installations 

within the last two years. Training of new personnel 

within three months of installation by a manufacturer’s 

technical representative is an acceptable substitution 

for this experience. In this case, provide proof of 

training.

r. Prepare the plan under the seal of a Utah 

Professional Engineer.

s. The Engineer reserves the right to retain these 

drawings up to 14 calendar days without granting an 

increase in the number of working days on the 

project. This duration is reduced to 7 days when the 

drawings are submitted electronically. This right 

applies each time the drawings are submitted or resubmitted. 

2. Element Shop Drawings:

a. Submit five sets of half-size, 11 x 17 inch sheets with 

a 11⁄2 inch blank margin on the left-hand edge.

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b. Place the project designation data in the lower righthand corner of each sheet.

c. Prepare shop drawings and stamp by Professional 

Engineer licensed in Utah.

d. Show all lifting inserts, hardware, or devices and

locations on the shop drawings for Engineer’s 

approval.

e. Show locations and details of the lifting devices, 

including supporting calculations, type, and amount of 

any additional reinforcing required for lifting. Design 

all lifting devices based on the no cracking criteria in 

Chapter 5 of the PCI Design Handbook.

f. Show minimum compressive strength attained prior to 

handling the precast elements.

g. Show Details of vertical adjusting hardware.

h. Do not order materials or begin work until receiving 

final approval of the shop detail drawings.

i. The Department will reject any elements fabricated 

before receiving written approval, or any elements 

that deviate from the approved drawings. The 

Contractor is responsible for costs incurred due to 

faulty detailing or fabrication.

j. The Engineer reserves the right to retain these 

drawings up to 14 calendar days without granting an 

increase in the number of working days on the 

project. This duration is reduced to 7 days when the 

drawings are submitted electronically. This right 

applies each time the drawings are submitted or resubmitted. 

3. Grouted Splice Couplers

a. Submit five copies of an independent test report 

confirming the compliance of the coupler with the 

following requirements:

1) Develop 100 percent of the specified tensile 

strength of the attached reinforcing bar. This 

equates to 90 ksi bar stress for an ASTM A 

615 bar and 80 ksi bar stress for an ASTM A 

706 bar.

2) Determine through testing, the amount of time 

required to provide 100 percent of the specified 

minimum yield strength of the attached 

reinforcing bar. Use this value to develop the 

assembly plan timing.

b. Submit an independent test report that includes data 

for each supplied coupler size. 

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c. Use the same grout in the construction that was used 

in the testing.

d. Submit the specification requirements for the grout 

including required strength gain to develop the 

specified minimum yield strength of the connected 

reinforcing bar.

4. Resistance Butt Welded Reinforcing Hoops

a. Submit five copies of proof that the manufacturer is 

approved by the California Department of 

Transportation for the bar size and diameter specified. 

Lists of approved fabricators can be found at the 

California Department of Transportation website 

(http://www.dot.ca.gov/hq/esc/approved_products_list

/pdf/PrequalFlashWeldedHoops.pdf).

. 

b. Submit five copies of the manufacturer’s quality 

Control (QC) manual for the hoop fabrication. Include 

the following information in the manual as a minimum:

1) The pre-production procedures for the 

qualification of material and equipment.

2) The methods and frequencies for performing 

QC procedures during production.

3) The calibration procedures and calibration 

frequency for all equipment.

4) The welding procedure specification (WPS) for 

resistance welding.

5) The method for identifying and tracking lots.

5. Structural Non-Shrink Grout

a. Submit a Certificate of Compliance to Engineer. 

b. Submit a proposed method for forming grout voids 

and installing the structural non-shrink grout, 

sequence, and equipment for grouting operation to 

Engineer for review for a minimum of 14 days. Obtain 

approval before placing grout.

B. Concrete Requirements

1. Submit substitutions for self-consolidating concrete mix 

designs to Engineer for approval as an alternate to the 

structural concrete for the precast elements.

2. Submit to the Engineer for approval a high early strength 

concrete mix or material data information that states the 

percentage of each component to be used depending on the 

closure pour concrete selected.

3. Regardless of the type of high early strength concrete 

proposed, submit substantive data that demonstrates the 

ability of the material to meet the specification requirements 

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with the proposed mix design at least two weeks prior to its 

use.

C. Defects and breakage of precast elements

1. Submit proposed written repair procedures for approval. 

D. Grout substitution in the couplers

1. Refer to this Section, article 2.1 paragraph E5a for additional 

certified test report requirements.

E. Installation of elements

1. Refer to this Section, article 3.2 paragraph A for changes 

warranted due to varying site conditions.

PART 2 PRODUCTS

2.1 MATERIALS

A. Concrete

1. Precast elements: Use Class AA (AE) concrete as specified 

in Section 03055 and on the plans. 

2. Bedding under elements: Use flowable fill conforming to the 

requirements of Section 03575.

3. High Early Strength Concrete: Use one of the following:

a. A high early strength concrete mix designed as 

follows:

1) Use air-entraining, Portland cement, fine and 

coarse aggregates, admixtures, water, and 

additives.

2) Use between 4 and 7 percent-entrained air.

3) Develop a mix that can attain a 6-hour 

compressive strength of 2500 psi, and a 7-day 

compressive strength of 4000 psi.

4) Additionally, develop a mix that contains 

shrinkage compensating additives such that 

there will be no separation of the closure pour 

concrete from the adjacent precast concrete.

5) Use a shrinkage-compensating additive that 

produces expansion in the high early strength 

concrete of no more than 3 percent.

b. A proprietary concrete mix may be used that meets 

the same physical requirements as those stated 

above.

B. Reinforcing Steel

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1. Conform to Section 03211.

2. Use coated reinforcing steel in all elements. 

3. Use reinforcing conforming to ASTM A 706 (weldable) for 

vertical reinforcing in the pier columns, transverse reinforcing 

in the pier columns, and any bar passing from the columns 

into the footing or pier cap. Use reinforcing conforming to 

ASTM A 615 for all other substructure elements.

4. Use continuous butt welded hoops or spiral reinforcing for 

transverse column reinforcing. Connect the ends of the 

continuous hoops by the resistance butt welding method. 

Hoop ends connected by lap welding will not be allowed. 

Other mechanically connected end devices are also not 

allowed.

5. Lap splices in vertical column reinforcing bars are not 

allowed unless specifically noted on the plans. 

C. Non- Shrink Grout

1. Use structural non-shrink grout for joints between precast 

elements as shown on the plans. 

a. Mix structural non-shrink grout just prior to use 

according to the manufacturer’s instructions.

b. Use gray, non-shrink grout concrete and containing 

no calcium chloride or admixture containing calcium 

chloride or other ingredient in sufficient quantity to 

cause corrosion to steel reinforcement.

c. Follow manufacturer’s recommendation for dosage of 

corrosion inhibitor admixture.

d. Use quick-setting, rapid strength gain, non-shrink, and 

high-bond strength grout. 

e. Warranty the in-place structural non-shrink grout 

performance and workmanship for two years. 

f. Repair or refund at the Department’s option any 

bonding failures that occur during the warranty period.

g. Use structural non-shrink grout that meets a minimum 

compressive strength of 4,000 psi within 24 hours 

when tested as specified in AASHTO T 106. 

h. Meet all the requirements of AASHTO T 160 with the 

exception that the Contractor-supplied cube molds will 

remain intact with a top firmly attached throughout the 

curing period. 

i. Use structural non-shrink grout with no expansion 

after seven days.

j. Refer to Table 1 for structural non-shrink grout 

requirements.

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Table 1

Structural Non-Shrink Grout

*Properties Requirements ASTM AASHTO

Accelerated Weathering As Specified in

ASTM or AASHTO C 666 T 260

Compressive Strength >5,000 psi @ 28 days T 106

Accepted Bond Strengths >1,000 psi @ 24 Hours C 882

Test Medium <3% White Utah Road Salt T 161

Accepted Weight Loss <15% @ 300 Cycles T 161

Length Change No expansion after 7 days T 160

*Certified test results from a private AASHTO accredited testing laboratory will 

suffice for acceptance.

D. Precast Concrete Elements

1. Use a Department Certified Concrete Precaster or a prequalified project site caster for concrete products according 

to the Department Quality Management Plan: PrecastPrestressed Concrete Structures.

2. Maintain a minimum compressive strength of 500 psi prior to 

stripping the form. Continuously wet cure the precast 

elements for 7-days commencing immediately after final 

finishing with all exposed surfaces covered. The precast 

elements will have a minimum cure of 14 days prior to 

placement. 

3. Supply test data such as slump, air voids, or unit weight for 

the fresh concrete and compressive strengths for the 

hardened concrete after 7, 14, and 28 days, if applicable.

E. Grouted Splice Couplers

1. Use grouted splice couplers to join precast elements as 

shown on the plans.

a. Provide couplers that use cementitious grout placed 

inside a steel casting.

b. Threaded connections may be used for the portions of 

the coupler that are placed within the precast element 

if the strength of the coupler meets or exceeds the 

requirements of this specification. 

2. The following reinforcing splice couplers are acceptable for 

use provided that the requirements of this specification are 

met. 

a. NMB Splice Sleeve 

Splice Sleeve North America, Inc.

192 Technology Drive, Suite J, 

Irvine, California 92618-2409

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www.splicesleeve.com

b. Dayton Superior DB Grout Sleeve

Dayton Superior 

Corporate Headquarters

7777 Washington Village Dr., Ste. 130

Dayton, OH 45459

www.daytonsuperior.com

c. Erico Lenton Interlok

ERICO United States

34600 Solon Road

Solon, Ohio 44139

www.erico.com

3. Use grouted splice couplers that are epoxy coated and can 

join epoxy coated reinforcing steel without removal of the 

epoxy coating on the spliced bar.

4. Use grouted splice couplers that can provide 100 percent of 

the specified tensile strength of the connected bar.

a. This equates to 90 ksi for reinforcing conforming to 

ASTM A 615 and 80ksi for reinforcing conforming to 

ASTM A 706.

5. Supply grout for the inside the couplers from the 

manufacturer of the coupler that is matched to the certified 

test report for the coupler.

a. Do not substitute any other grout in the couplers 

unless additional certified test reports are submitted 

for the grout/coupler system. 

F. Corrugated Metal Pipe

1. Conform to AASHTO Standard Specifications for Highway 

Bridges and AASHTO M 36 or AASHTO M 245

G. Leveling Devices

1. The plans show fabricated steel leveling devices. Alternate 

devices may be used provided that they can support the 

anticipated loads.

H. Vertical Joint Seals

1. Use natural rubber or neoprene sheet with a durometer of 

50-60, meeting the requirements of ASTM D 2240.

2.2 QUALITY ASSURANCE

A. Precast Substructure Elements

1. The Department pre-qualifies pre-cast and site-cast 

manufacturers according to the UDOT Quality Management 

Plan: Pre-cast/Prestressed Concrete Structures.

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2. Permanently mark each precast element with date of casting 

and supplier identification. Stamp markings in fresh 

concrete.

3. Prevent cracking or damage of precast elements during 

handling and storage.

4. Replace defects and breakage of precast elements

a. Members that sustain damage or surface defects 

during fabrication, handling, storage, hauling, or 

erection are subject to review or rejection.

b. Obtain approval before performing repairs.

c. Repair work must reestablish the elements’ structural 

integrity, durability, and aesthetics to the satisfaction 

of the Engineer.

d. Determine the cause when damage occurs and take 

corrective action.

e. Failure to take corrective action, leading to similar 

repetitive damage, can be cause for rejection of the 

damaged element. 

f. Cracks that extend to the nearest reinforcement plane 

and fine surface cracks that do not extend to the 

nearest reinforcement plane but are numerous or 

extensive are subject to review and rejection.

g. Full depth cracking and breakage greater than one 

foot are cause for rejection.

5. Construct precast elements to tolerances shown on the 

plans.

6. The plant will document all test results. The quality control 

file will contain at least the following information:

a. Element identification

b. Date and time of cast

c. Concrete cylinder test results 

d. Quantity of used concrete and the batch printout

e. Form-stripping date and repairs if applicable

f. Location/number of blockouts and lifting inserts

g. Temperature and moisture of curing period

h. Document lifting device details, requirements, and 

inserts

B. Continuous Butt Welded Hoops

1. Provide samples for Quality Assurance testing in 

conformance with the provisions in these specifications.

2. Perform all production tests for all size splices (by the 

contractor’s independent laboratory). Remove four sample 

splices from each lot of completed splices. Test according to 

ASTM A 370. The Engineer may select the sample splices 

for hoops either at the job site or at the fabrication facility.

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C. Grouted Splice Couplers

1. The performance of grouted splice couplers is related to the 

embedment length of the bars and the compressive strength 

of the grout. 

a. Check the length of rebar anchor dowel to make sure 

they meet the minimum embedment specified in the 

manufacturer’s manual.

b. Monitor shim thickness between the precast elements 

to ensure that the reinforcing extensions are within 

the manufacturers recommended tolerance. 

c. Monitor the grout mixing, water to grout ratio, mixing 

time, and shelf life of the grout for conformance with 

the manufacturers written instructions.

d. Monitor the grouting operation to verify that all 

sleeves have been filled.

e. Make four sets of three - two inch cube molds in 

heavy brass molds with cover plates for testing 

according to AASHTO T 106.

f. Verify that all sleeves are protected from any 

vibration, shock, or other excessive movement until 

temporary bracing is removed.

g. Check the temperature of the sleeve at the time of 

grouting (50 degrees F minimum) and during curing. 

PART 3 EXECUTION

3.1 FABRICATION

A. Do not place concrete in the forms until the Engineer has inspected 

and approved all the materials in the elements.

B. Provide the Engineer a tentative casting schedule at least two 

weeks in advance to make inspection and testing arrangements. A 

similar notification is required for the shipment of precast elements 

to the job site.

C. Do not place concrete in the forms until the Engineer has inspected 

the form and has approved the placement of all materials in the 

precast elements.

D. Finish the precast elements according to Section 03310. Trowel 

finish the top surface of all precast concrete elements. 

3.2 GENERAL PROCEDURE FOR ALL INSTALLATION OF ELEMENTS

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A. Review the approved assembly plan. If changes are warranted due 

to varying site conditions, resubmit the plan for review and 

approval.

B. Dry fit adjacent elements in the shop if noted on the plans. The 

fabricator may opt to dry fit elements in any case.

C. Establish working points, working lines, and benchmark elevations 

prior to placement of all elements.

D. Check the condition of the receiving bonding surface prior to 

connecting elements and take any necessary measures to remove 

items such as dust, rust, and debris to provide the satisfactory 

bonding required between the protruding reinforcing bars element 

and the grouted couplers. 

E. Place elements in the sequence and according to the methods 

outlined in the assembly plan. Adjust the height of each element by 

means of leveling devices or shims.

3.3 CONNECTION PROCEDURE USING GROUTED SPLICE COUPLERS

A. Use personnel that are familiar with installation and grouting of 

splice couplers that have completed at least two successful projects 

in the last two years.

1. Training of new personnel within three months of installation 

by a manufacturer’s technical representative is an 

acceptable substitution for this experience. 

B Remove and clean all debris from the joints prior to application of 

non-shrink grout.

C. Keep bonding surfaces free from laitance, dirt, dust, paint, grease 

oil, or any contaminants other than water.

D. Saturate Surface DRY (SSD) all joint surfaces prior to connecting 

the elements. 

E. Use heaters in freezing temperatures to maintain a minimum 

temperature of 50 degrees F. Monitor the temperature of the 

covered sleeves until the temporary bracing is removed.

F. Follow the recommendations of the manufacturer for the installation 

and grouting of the couplers.

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G. Install with couplers above a horizontal joint

1. Determine the thickness of shims to provide the specified 

elevation within tolerance.

2. Mix the non-shrink grout according to the supplier’s 

recommendations including preparation and application.

3. Place non-shrink grout on the interface between the two 

elements being joined prior to setting the element. Crown 

the thickness of the grout toward the center of the joint so 

that the grout can be displaced outward as the element is 

lowered onto the joint. Take precautions to prevent the nonshrink grout from entering the coupler above (e.g. grout 

dams or seals).

4. Set the element in place. Engage all couplers in the joint. 

Allow the non-shrink grout to seep out of the joint.

5. Trowel off excess non-shrink grout to form a neat joint once 

the element is set, plumbed, and aligned. Pack grout into 

any voids around the joint perimeter.

6. Flush out the coupler with clean potable water.

7. Mix the special coupler grout according to the 

manufacturer’s recommendations for methods and 

proportions of mix and water.

8. Make four sets of three 2-inch cube specimens for testing. 

Cure the specimens according to AASHTO T 106. Test one 

set of cubes for compressive strength at a minimum of 24 

hours (or to determine when to release bracing) and 28-

days. Store extra sets for longer term testing, if necessary.

9. Pump the coupler grout into the coupler that is cast into the 

element. Start from the lower port. Pump until the grout is 

flowing freely from the upper port.

10. Cap the upper port first and then remove the nozzle to cap 

the lower port. Proceed to the next coupler in a defined 

sequence.

11. Cure the joint according to the non-shrink grout 

manufacturer’s recommendations.

H. Installation with couplers below a horizontal joint

1. Determine shim thickness to provide the specified elevation 

within tolerance.

2. Prior to setting the element:

a. Mix the special coupler grout paying strict attention to 

the manufacturer’s recommendations for methods 

and proportions of mix and water.

b. Clean debris from the interior using compressed air. 

Remove any rain water using a vacuum that can 

remove water from the confined space in the coupler.

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c. First, pour the coupler grout into the coupler by 

pouring or pumping into the coupler. It is acceptable 

to fill the coupler to the top.

d. Second, place non-shrink grout on the interface 

between the two elements being joined. Crown the 

thickness of the grout toward the center of the joint so 

that the grout can be displaced outward as the 

element is lowered onto the joint. 

e. Trowel off excess non-shrink grout to form a neat joint 

once the element is set, plumbed, and aligned. Pack 

grout into any voids around the joint perimeter.

I. Installation of coupler in vertical joints (horizontal bar/coupler 

connection)

1. Establish a method to provide the specified alignment and 

spacing of the elevation within tolerance.

2. Use washers or seals to prevent mixing of the non-shrink 

joint grout and the coupler grout.

3. Set the element in place. Engage all couplers in the joint. 

4. Flush out the couplers with clean potable water once the 

element is set, plumbed, and aligned.

5. Mix the special coupler grout paying strict attention to the 

manufacturer’s recommendations for methods and 

proportions of mix and water.

6. Pump the coupler grout into the coupler that is cast into the 

element. Start from the port closest to the joint. Pump until 

the grout is flowing freely from the other port.

7. Cap the port farthest from the joint first and then remove the 

nozzle to cap the other port. Proceed to the next coupler in 

a defined sequence.

8. Form the edges of the joint and place non-shrink grout into 

the joint.

9. Cure the joint according to the non-shrink grout 

manufacturer’s recommendations.

3.4 FOOTINGS

A. Lift footing segments as shown in the assembly plan using lifting 

devices as shown on the shop drawings.

B. Set footing in the proper horizontal location. Check for proper 

alignment within specified tolerances.

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C. Adjust vertical leveling devices prior to full release of the element 

from the crane to facilitate the vertical adjustment process. This will

reduce the amount of torque required to turn the bolts in the 

leveling devices. Check for proper grade within specified 

tolerances.

D. Check the spacing of dowels or grouted splice couplers between 

adjacent footings that are to support common elements in future 

stages of construction. The use of bi-level templates and jigs is 

recommended. Adjust the location of the footing if required.

E. Pour flowable bedding concrete through the ports for spread 

footings supported on soil or rock. Start from the center of the 

footing and proceed toward the outside edges. Verify that bedding 

concrete is filling the entire void between the footing and the 

subgrade.

F. Place concrete around pile tops as shown on the plans for footings 

supported on drilled shafts or piles. Allow this concrete to flow 

partially under the footing. The entire underside of the footing need 

not be filled with concrete.

G. Do not remove the installation bolts or proceed with the installation 

of elements above the footing until the compressive test result of 

the cylinders for bedding concrete or pile connection concrete has 

reached the specified minimum values.

3.5 PIER COLUMNS

A. Lift column element as shown in the assembly plan using lifting 

devices as shown on the shop drawings.

B. Survey the elevation of the element directly below the column. 

Provide shims to bring the bottom of the column to the required 

elevation.

C. Measure the elevation of the top of the shim stack and the top of 

the projecting dowels. Verify that the elevations and dowel 

extensions are within specified tolerances.

D. A dry fit of the column is recommended until work crews become 

more familiar with the process. Set column in the proper horizontal 

location. Check for proper horizontal and vertical alignment within 

specified tolerances. Remove and adjust the shims and reset the 

column if the column is not within tolerance.

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E. Check the dowel spacing or grouted splice couplers between 

adjacent columns that will support common elements in future 

stages of construction. The use of bi-level templates and jigs is 

recommended. Adjust the location of the footing if required. Slight 

tilting of the column within tolerances is permitted. 

F. Set the column and install the couplers as described in this Section, 

article 3.3 once the connection geometry is established and 

checked. 

G. Install temporary bracing if specified in the assembly plan. 

H. Allow the grout in the coupler to cure until the coupler can resist 

100 percent of the specified minimum yield strength of the bar prior 

to removal of bracing and proceeding with installation of 

components above the pier column. The required strength of the 

grout for this is based on the certified test report. Verify the 

strength of the grout by testing cube samples according to 

AASHTO T 106.

3.6 PIER CAPS

A. Lift pier cap element as shown in the assembly plan using lifting 

devices as shown on the shop drawings.

B. Survey the elevation of the column directly below the cap. Provide 

shims to bring the bottom of the cap to the required elevation. 

Measure the elevation of the top of the shim stack and the top of 

the projecting dowels. Verify that the elevations and dowel 

extensions are within specified tolerances.

C. A dry fit of the cap is recommended until work crews become more 

familiar with the process. Set cap in the proper horizontal location. 

Check for proper horizontal and vertical alignment within specified 

tolerances. Remove and adjust the shims and reset the cap if the 

cap is not within tolerance.

D. Set the cap and install the couplers as described in this Section, 

article 3.3 once the connection geometry is established and 

checked. 

E. Install temporary bracing if specified in the assembly plan. 

F. Allow the grout in the coupler to cure until the coupler can resist 

100 percent of the specified minimum yield strength of the bar prior 

to removal of bracing and proceeding with installation of 

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components above the pier cap. The required strength of the grout 

for this is based on the certified test report. Verify the strength of 

the grout by testing cube samples according to AASHTO T 106.

3.7 WALL PANELS

A. Wall panels consist of the following:

1. Cantilever Abutment Stems

2. Wingwall stems

3. Integral abutment pile cap stems

4. Abutment Backwalls and Cheekwalls

B. Lift wall panel element as shown in the assembly plan using lifting 

devices as shown on the shop drawings.

C. Wall panels supported on precast concrete elements (footing or 

stem) 

1. Survey the elevation of the base directly below the panel. 

Provide shims to bring the bottom of the panel to the 

required elevation. Measure the elevation of the top of the 

shim stack and the top of the projecting dowels. Verify that 

the elevations and dowel extensions are within specified 

tolerances. 

2. A dry fit of the panel is recommended until work crews 

become more familiar with the process. Set panel in the 

proper horizontal location. Check for proper horizontal and 

vertical alignment within specified tolerances. Remove and 

adjust the shims and reset the panel if the panel is not within 

tolerance. 

3. Set the panel and install the couplers as described in this 

Section, article 3.3 once the connection geometry is 

established and checked.

4. Install temporary bracing if specified in the assembly plan. 

5. Allow the grout in the coupler to cure until the coupler can 

resist 100 percent of the specified minimum yield strength of 

the bar prior to removal of bracing and proceeding with 

installation of components above the panel. The required 

strength of the grout for this is based on the certified test 

report. Verify the strength of the grout by testing cube 

samples according to AASHTO T 106.

6. Place concrete inside the blockouts and cure if the panels 

contain corrugated pipe blockouts.

D. Wall panels supported on piles or drilled shafts (integral abutments)

1. Lift wall panel as shown in the assembly plan using lifting 

devices as shown on the shop drawings.

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2. Set the panel in the proper horizontal location. Check for 

proper alignment within specified tolerances.

3. Adjust the devices prior to full release from the crane if 

vertical leveling devices are used. This will reduce the 

amount of torque required to turn the bolts in the leveling 

devices. Check for proper grade within specified tolerances.

4. Check the spacing of dowels or grouted splice couplers 

between adjacent panels that are to support common 

elements in future stages of construction. The use of bi-level 

templates and jigs is recommended. Adjust the location of 

the panel if required.

5. Place concrete around pile tops as shown on the plans. 

Allow concrete to flow partially under the panel. The entire 

underside of the panel need not be filled with concrete.

6. Do not remove the installation bolts (if used) or proceed with 

the installation of elements above the panel until the 

compressive test result of the cylinders for the pile 

connection concrete has reached the specified minimum 

values. 

3.8 PRECAST BEAM SEATS

A. Lift the precast beam seats as shown in the assembly plan using 

lifting devices as shown on the shop drawings.

B. Set beam seat in the proper horizontal location.

1. Check for proper alignment within specified tolerances.

C. Adjust vertical leveling devices.

1. Check for proper grade within specified tolerances.

D. Install temporary bracing if specified in the assembly plan. 

E. Pour or pump grout through the blockouts in the seat.

1. Start from the center of the seat and proceed toward the 

outside edges.

2. Verify that grout is filling the entire void between the seat 

and the substructure element below.

F. Grind beam seat to achieve the specified seat elevation tolerance if 

required.

1. Grind to a maximum depth of 1

/8 inch.

END OF SECTION

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Example Specification C2:

Source: Utah Department of Transportation

Title: Precast Concrete Deck Panel 

Use: Precast concrete deck panels with longitudinal post-tensioning 

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May 24, 2010

SPECIAL PROVISION

PROJECT #

PIN #

SECTION 03339S

PRECAST CONCRETE DECK PANEL 

Delete Section 03339 in its entirety and replace with the following:

PART 1 GENERAL

1.1 SECTION INCLUDES

A. This work consists of furnishing, erecting, and installing all precast 

concrete deck panels including all necessary materials and 

equipment to complete the work as shown on the plans. The use of 

cast-in-place concrete is not an acceptable alternative for precast 

panels.

B. Procedures for preparing and installing structural non-shrink grout.

C. Placing structural non-shrink grout into the camber strips, filling the 

shear stud blockouts and, all other blockouts in the bridge precast 

concrete deck panels to produce a finished deck.

 

D. Procedures relating to preparing bridges for widening and grinding 

deck panels.

E. Procedures relating to installing new shear studs on top flanges of 

existing steel girders and installing shear connectors to the top 

flanges of existing concrete or prestressed beams as shear studs.

F. Procedures for full depth precast concrete deck panel.

1.2 RELATED SECTIONS

A. Section 02982: Bridge Concrete Grinding

B. Section 03055: Portland Cement Concrete

C. Section 03211: Reinforcing Steel and Welded Wire

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D. Section 03251S: Post Tensioning Concrete

E. Section 03310: Structural Concrete

F. Section 03372: Thin Bonded Polymer Overlay

G. Section 03412: Prestressed Concrete

1.3 REFERENCES

A. AASHTO M 111: Standard Specifications for Zinc (Hot-Galvanized) 

Coatings on Products Fabricated From Rolled, Pressed and Forged 

Steel Shape Plates, Bars, and Strip

B. AASHTO M 169: Standard Specification for Steel Bars, Carbon and 

Alloy, Cold-Finished

C. AASHTO M 235: Standard Specification for Epoxy Resin 

Adhesives

D. AASHTO M 270: Structural Steel for Bridges 

E. AASHTO T 106: Compressive Strength of Hydraulic Cement 

Mortar

F. AASHTO T 160: Length Change of Hardened Hydraulic Cement 

Mortar and Concrete

G. AASHTO T 161: Standard Method of Test for Resistance of 

Concrete to Rapid Freezing and Thawing

H. AASHTO T 260: Standard Method of Test for Sampling and 

Testing Chloride Ion in Concrete and Concrete Raw Materials

I. AASHTO/AWS D1.5 2008 Bridge Welding Code

J. ASTM A 108: Standard Specification for Steel Bar, Carbon and 

Alloy, Cold-Finished

K. ASTM A 109: Standard Specification for Steel Carbon Cold-rolled 

Strip

L. ASTM A 500: Standard Specification for Cold-Formed Welded and 

Seamless Carbon Steel Structural Tubing in Rounds and Shapes

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M. ASTM A 706: Standard Specification for Low-Alloy Steel Deformed 

and Plain Bars for Concrete Reinforcement

N. ASTM C 494: Standard Specification for Chemical Admixtures for 

Concrete

O. ASTM C 666: Standard Test Method for Resistance of Concrete to 

Rapid Freezing and Thawing

P. ASTM C 882: Standard Test Method for Bond Strength of EpoxyResin Systems Used With Concrete By Slant Shear

Q. ASTM E 1512: Standard Test Methods for Testing Bond 

Performance of Bonded Anchors

R. ANSI/AWS C 6.2-89: Specification for Friction Welding of Metals

S. PCI Design Handbook, Fifth Edition with all Interims and Errata

T. UDOT Quality Management Plan

1.4 DEFINITIONS NOT USED

1.5 SUBMITTALS

A. Submit the following to the Engineer for written approval:

1. Shop Drawings: 

a. Submit five sets half-size, 11 x 17 inch sheets with a 

11⁄2 inch blank margin on the left-hand edge.

b. Place the project designation data in the lower righthand corner of each sheet.

c. Prepare shop drawings stamped by a Professional 

Engineer licensed in Utah. 

d. Design, show, and locate all lifting inserts, hardware 

or devices, and vertical adjustment hardware on the 

shop drawings for the Engineer’s approval. Design 

lifting hardware according to the provisions of Chapter 

5 of the PCI Design Handbook. 

e. Show type and size of longitudinal post-tensioning 

anchorage assembly and ducts. Design local zone 

reinforcing for the anchorage assembly.

f. Submit a Certificate of Compliance for non-shrink 

grout to the Engineer for approval.

g. Do not order materials or begin work until receiving 

final approval of the shop detail drawings.

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h. Do not deviate from the approved shop drawings 

unless authorized in writing. Contractor is responsible 

for costs incurred due to faulty detailing or fabrication.

i. The Engineer reserves the right to retain these 

drawings up to 14 calendar days without granting an 

increase in the number of working days on the 

project. This duration is reduced to 7 days when the 

drawings are submitted electronically. This right 

applies each time the drawings are submitted or resubmitted. The Department will reject units fabricated 

before receiving written approval.

2. Erection Plans:

a. Submit five sets half-size, 11 x 17 inch sheets with a 

11⁄2 inch blank margin on the left-hand edge.

b. Place the project designation data in the lower righthand corner of each sheet. 

c. Prepare drawings and supporting calculations 

stamped by a Professional Engineer licensed in Utah.

d. Check that all handling and erection bracing conform 

to Chapter 5 of the PCI Design Handbook.

e. Include the following at a minimum on the erection 

plans:

1) Minimum clearances of reinforcing to panel 

edges.

2) Locations and details of lifting devices 

including supporting calculations. Design all 

lifting devices based on the no cracking criteria 

in Chapter 5 of the PCI Design Handbook.

3) Type and amount of any additional reinforcing 

required.

4) Calculations showing that tensile stresses on 

both faces do not exceed the modulus of 

rupture during the handling, fabrication, 

shipping, and erection of the panel. 

5) Minimum compressive strength attained prior 

to handling the panels.

6) Load distribution.

7) Cables and lifting equipment.

8) Details of vertical adjusting hardware.

f. Include details showing the erection and installation of 

the proposed deck panels in accordance with the 

design plans. 

g. Submit Erection Plan drawings including the following 

minimum information:

1) Crane and pick locations

2) Crane charts

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3) Panel erection and sequence

h. Submit to the Engineer for review a proposed method 

for forming the camber strips and installing the 

structural non-shrink grout, sequence, and equipment 

for grouting operation. Obtain approval prior to 

placing structural non-shrink grout begins.

i. Submit a method of forming closure pours at joints 

between precast panels.

j. The Engineer reserves the right to retain these 

drawings up to 14 calendar days without granting an 

increase in the number of working days on the 

project. This duration is reduced to 7 days when the 

drawings are submitted electronically. This right 

applies each time the drawings are submitted or resubmitted. 

3. Submit substitutions for self-consolidating concrete (SCC) 

mix designs to the Engineer for approval as an alternate to 

the structural concrete for the precast deck panels. 

B. Submit for Materials. Refer to this Section, article 2.1.

1. Supply test data such as slump, air voids, or unit weight after 

7, 14, and 28 days for fresh concrete and compressive 

strengths for the hardened concrete.

C. Submit for High Early Strength Concrete. Refer to this Section, 

article 2.1, paragraph H.

1. Submit material data information that states the percentage 

of each component used.

2. Provide substantive data at least two weeks prior to use that 

demonstrates the ability of the material to meet the 

specification requirements with the proposed mix design 

regardless of the type of high early strength concrete 

proposed.

PART 2 PRODUCTS

2.1 MATERIALS 

A. Mild Reinforced Panel: Use Class AA (AE) concrete for precast 

concrete deck panels as specified in Section 03055 and on the 

plans. 

B. Prestressed Panel: Use Class AA (AE) concrete according to 

Section 03055 except as modified by Section 03412 for 

Prestressed Concrete Panels. Use 3⁄4 inch nominal aggregate.

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C. Use coated reinforcing steel as specified in Section 03211. 

D. Use mechanical threaded couplers when specified for precast 

concrete deck panel reinforcing according to Section 03211.

1. Do not use lap splices for mild reinforcement within the 

panel.

2. Lap splices are acceptable in cast-in-place closure pours.

E. Use embedded prefabricated steel pocket blockouts when shown 

on the plans that conform to the following:

1. Use cold formed rectangular steel tubing meeting the 

requirements of ASTM A 500 Grade B.

2. Use a steel top plate meeting the requirements of AASHTO 

M 270 Grade 36. Higher strength grades of steel may be 

substituted with prior approval from the Engineer.

3. Galvanize the steel assembly after fabrication according to 

the requirements of AASHTO M 111.

4. Use plastic pipe for grout ports and vents. 

F. Use lifting devices that meet the following criteria:

1. Use devices that can support the required vertical and 

horizontal forces with the applicable safety factors as 

specified in the PCI Design Handbook, Chapter 5. 

2. Use a device that will have 23⁄4 inch top cover and 1 inch 

bottom cover after installation. This may require partial 

removal of the device after installation.

3. Galvanize the leveling device after fabrication according to 

the requirements of AASHTO M 111.

G. Use structural non-shrink grout for camber strips, shear stud 

blockouts, keyway blockouts, and other blockouts shown on the 

plans. 

1. Use a mix design according to Section 03055 if adding more 

than 15 lb of coarse aggregate (size No. 8) or larger per 50 

lb bag of structural non-shrink grout.

2. Mix structural non-shrink grout just prior to use according to 

the manufacturer’s instructions.

3. Use non-shrink, gray grout concrete containing no calcium 

chloride or admixture containing calcium chloride or other 

ingredient in sufficient quantity to cause corrosion to steel 

reinforcement.

4. Follow manufacturer’s recommendation for corrosion 

inhibitor admixture dosage.

5. Use quick-setting, rapid strength gain, non-shrink, and highbond strength grout. 

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6. Warranty the in-place structural non-shrink grout 

performance and workmanship for two years. 

7. Repair or refund at the Department’s option any bonding 

failures that occur during the warranty period.

8. Refer to Table 1 for structural non-shrink grout requirements.

Table 1

Structural Non-Shrink Grout

*Properties Requirements ASTM AASHTO

Accelerated Weathering As Specified in

ASTM or AASHTO C 666 T 260

Compressive Strength >5,000 psi @ 28 days T 106

Accepted Bond Strengths >1,000 psi @ 24 Hours C 882

Test Medium <3% White Utah Road Salt T 161

Accepted Weight Loss <15% @ 300 Cycles T 161

Length Change No expansion after 7 days T 160

*Certified test results from a private AASHTO accredited testing laboratory will 

suffice for acceptance.

H. High Early Strength Concrete for closure pours: Use one of the 

following methods:

1. Design a high early strength concrete mix and obtain the 

Engineer’s approval. 

a. Use air-entraining, Portland cement, fine and coarse 

aggregates, admixtures, water, and additives. 

b. Use between 4 to 7 percent-entrained air. 

c. Develop a mix that can attain a 6-hour compressive 

strength of 2,500 psi and a 7-day compressive 

strength of 4,000 psi. 

d. Develop a mix that contains shrinkage compensating 

additives such that there will be no separation of the 

closure pour concrete from the adjacent precast 

concrete. 

e. Use a shrinkage-compensating additive that produces 

expansion in the high early strength concrete of no 

more than 3 percent.

2. A proprietary concrete mix that meets the same physical 

requirements as those stated above may be used. 

2.2 CONCRETE CORROSION INHIBITOR ADMIXTURE

A. The concrete corrosion inhibitor admixture will contain a minimum 

of 30 percent calcium nitrite by mass and formulated to meet ASTM 

C 494 requirements for Type C, accelerating admixture.

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B. Use a dosage rate of 4 gal/yd3 unless otherwise directed by the 

manufacturer.

C. Use the admixture in all new concrete and grout placed.

2.3 PRESTRESSING STRAND, POST TENSIONING AND SHEAR 

CONNECTORS

A. Refer to Section 03412: Prestressed Concrete for requirements.

B. Refer to Section 03251S: Post Tensioning Concrete for bar, 

strand, grout and other requirements.

C. Fabricate new shear studs from cold-drawn bars, Grades 1015, 

1018 or 1020, conforming to AASHTO M 169 standard quality, and 

have a minimum tensile strength of 60.0 ksi.

1. Use headed anchor studs for shear connectors conforming 

to dimensions showing on the plans. 

2. Use steel conforming to the requirement of AASHTO M 169. 

3. Automatically end weld studs in the shop or field with 

equipment designed for stud welding operations. 

4. Use equipment having capacity adequate for the size of stud 

welded.

D. Use a low carbon grade suitable for welding that will conform to 

ASTM A 109 for the caps if steel, flux-retaining caps are used.

E. Concrete girders:

1. Use T- Headed bars consisting of deformed rebar with steel 

plates friction-welded to one end of the rebar. Friction 

welding conforms to the approved quality control manual and 

the Specification for Friction Welding of Metals, ANSI/AWS 

C6.2.

2. Use deformed rebar that conforms to ASTM A 706, Grade 

60.

3. Cut plate heads for T-Headed bars from flats of hot-rolled 

steel conforming to ASTM A 108.

4. Use an approved epoxy grout to develop minimum pullout 

strength in T-headed bar anchorage as shown on the Plan.

2.4 ADHESIVE DOWELED ANCHORS

A. Use Epoxy resin adhesive for anchors that conform to AASHTO M 

235 Standard Specification for Epoxy Resin Adhesives.

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2.5 QUALITY ASSURANCE

A. The Department pre-qualifies pre-cast and site-cast fabricators 

according to the UDOT Quality Management Plan: Precast/Prestressed Concrete Structures. Only fabricators prequalified in Category Two will be accepted.

B. Permanently mark each precast unit with date of casting and 

supplier identification. Stamp markings in fresh concrete.

C. Prevent cracking or damage during handling and storage of precast 

units.

D. Defects and Breakage of Prestressed and Nonstressed Elements:

1. Elements that sustain damage or surface defects during 

fabrication, handling, storage, hauling, or erection are 

subject to review and rejection. 

2. Write proposed repair procedures and obtain approval 

before performing repairs. 

3. Repair work must reestablish the element’s structural 

integrity, durability, and aesthetics to the satisfaction of the 

Engineer. 

4. Determine the cause of any damage and take corrective 

action. 

5. Failure to take corrective action leading to similar repetitive 

damage is cause for rejection of the damaged elements. 

6. Cracks that extend to the nearest reinforcement plane and 

fine surface cracks that do not extend to the nearest 

reinforcement plane but are numerous or extensive are 

subject to review and rejection. 

7. Full depth cracking and breakage greater than 12 inches in 

length are cause for rejection.

E. Construct panels to tolerances shown on the plans or in the 

specifications. 

PART 3 EXECUTION

3.1 FABRICATION

A. Do not place concrete in the forms until the Engineer has inspected 

and approved the placement of all materials in the deck panels.

B. Finish the precast concrete deck panels following Section 03310. 

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C. Wet cure the deck panels for 14 consecutive days. This cure is to 

begin immediately after performing the final finish. 

1. Wet cure panels by covering all exposed surfaces with wet 

burlap, cotton mats, or both, and plastic sheets. 

2. Maintain a saturated condition for the burlap and cotton for 

the entire duration of the 14 days ±7 days. 

3. A 10 percent pay incentive exists for wet cure durations of 

21 consecutive days. A 10 percent pay disincentive exists 

for durations provided at the minimum required 7 days.

D. Perform prestressing according to Section 03412 Prestressed 

Concrete.

E. Do not strip the forms before the precast panels have obtained a 

minimum compressive strength of 500 psi. 

3.2 NEW SHEAR STUDS ON EXISTING STEEL GIRDERS AND 

CONCRETE BEAMS

A. Installation of the Shear Connectors

1. Install shear connectors at the locations shown on the plans.

2. Weld shear studs to steel girders or plates embedded in 

prestressed concrete according to AWS specifications. 

a. Adjust studs as necessary to provide clearance for 

bolts in existing bolted splices.

b. Use method and equipment recommended by the 

manufacturer of the studs and approved by the 

Engineer. 

c. Field weld studs using friction welding. Conform to 

the approved quality control manual and the 

Specification for Friction Welding of Metals 

ANSI/AWS C.6.2-89.

3. Field drill holes in the top flange of existing concrete and 

prestressed concrete beams and install shear studs 

according to manufacturer’s recommendations. 

a. Locate all internal beam reinforcing prior to drilling 

holes. 

b. Avoid drilling through reinforcing

c. Use method and equipment recommended by the 

manufacturer of the studs, epoxy grout, as approved 

by the Engineer.

3.3 PLACING PRECAST CONCRETE DECK PANELS

A. Fully brace concrete beams or steel girders prior to placing panels.

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B. Place the precast concrete deck panels as shown on the plans or 

approved working drawings.

C. Adjust leveling devices to bring panels to the elevations shown on 

the Plans. Torque all leveling devices to within 15 percent of each 

other to provide proper distribution of panel weight to the supporting 

beams.

D. Prevent shifting of the precast concrete deck panels during the 

joining of all the deck panels.

3.4 LONGITUDINAL POST TENSIONING

A. Cure Precast panels 28-days before tensioning of any postinstalled cables or rods.

B. Design and show all post-tensioning hardware and blockouts if 

required. Manufactured designed proprietary hardware is 

acceptable with the Engineer’s approval.

C. Clean and remove all debris from blockouts.

D. Set final elevations after all panels are in place.

E. Grout shear keyway between panels.

F. Do not begin stressing operations until the concrete reaches the 

strength and age designated on the plans. Stress strands within 72 

hours of panel placement and transverse joint grouting.

G. Do not post tension until the shear key grout has attained a 

compressive strength of 500 psi (based on manufacturer’s data).

H. Install strands as shown on the plans.

I. Fully tension strand and grout all ducts according to Section 

03251S.

J. Visually inspect the shear stud installation and connection details. 

Place structural non-shrink grout in the girder camber strips and 

shear stud blockouts in a continuous operation complete without 

voids.

3.5 INSTALLATION OF HEADED T BARS AND ANCHORS

A. Adhesive doweled anchors:

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1. Use items such as reinforcing, bar dowels, reinforcing bars, 

threaded rods, and bolts as shown in the plans and 

connected using adhesive dowel into concrete.

2. Weld heads on bars according to the requirements of the 

AASHTO/AWS D1.5 2008 Bridge Welding Code.

3. Drill, brush, clean all holes, and install all anchors according 

to manufacturer’s published recommendations as well as all 

applicable specifications.

4. Inspection is required for installation of reinforcement or 

threaded rods.

5. Install adhesive anchors and test according to the epoxy 

anchor test schedule and as follows:

a. Testing through the blockout is at the contractor’s risk. 

Repair damaged beams, girders, and panels as 

instructed by the Engineer. Panel may be rejected if 

not repaired as instructed.

b. Test 25 percent of the first 40 anchors installed and 

10 percent of all anchors installed thereafter.

c. Test the previous ten installed anchors and the next 

five installed anchors if any failures occur.

d. Allow anchor adhesives to cure 48 hours prior to 

testing.

e. Tension test according to ASTM E 1512.

f. Provide minimum capacity as defined in Table 2 

below.

Table 2

Epoxy Anchor Test Schedule For Anchors Installed

in Hard Rock Concrete

(2000 psi min. Strength)

Reinforcing bars

(fy = 60 ksi)

Bolts or threaded rods

(fy = 36 ksi)

Bar 

size

Minimum 

embedment

Tension 

test load 

(0.9fy)

Anchor 

diameter

Minimum 

embedment

Tension 

test load*

#4 6 inches 10800# 3⁄8 inch 5 inches 3384#

#5 7 inches 16700# 1⁄2 inch 7 inches 5400#

#6 9 inches 23800# 5⁄8 inch 8 inches 9390#

#7 10 inches 32400# 3⁄4 inch 10 inches 13530#

#8 12 inches 42700# 7⁄8 inch 12 inches 18417#

#9 13 inches 54000# 1 inch 13 inches 24050#

#10 16 inches 68600# 11⁄4 inch 15 inches 37580#

#11 18 inches 84200#

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Notes: * allowable loads equal 1/2 test load values

3.6 PREPARATION AND INSTALLATION OF STRUCTURAL NON-SHRINK 

GROUT

A. Clean and remove all debris from the camber strips and blockouts 

prior to placement of the structural non-shrink grout. 

B. Keep bonding surfaces free from laitance, dirt, dust, paint, grease, 

oil, rust, or any contaminant other than water.

C. Form the girder camber strips as shown on the plans after installing 

shear studs at the locations shown on the plans.

D. Pre-test grout material installation under field conditions in a grout 

pocket and camber strip mock-up prior to construction of the deck 

to determine grout flowability and whether subsequent cracking will 

occur. Include in the mock-up at least two shear connector pockets 

and a camber strip that is of the same configuration as the actual 

bridge. 

1. The Engineer will determine the required corrective action.

2. Proceed with grouting process at the Engineer’s direction.

E. Saturate surface dry (SSD) all surfaces receiving structural nonshrink grout. 

F. Mix and place product following manufacturer’s recommendations 

for preparation and installation. 

G. Grout the shear stud blockouts and girder camber strips using 

structural non-shrink grout. Place structural non-shrink grout in the 

girder camber strips and shear stud blockouts in a continuous 

operation within a panel. Do not allow voids in the grout for the 

girder camber strips and shear stud blockouts.

H. Do not apply superimposed dead loads or live loads to the precast 

concrete deck panels until the structural non-shrink grout in the 

shear stud blockouts and the girder camber strips has reached a 

strength of 500 psi based on manufacturer’s published data.

I. Fill all surface voids with non-shrink grout including lifting device 

blockouts and grout ports.

J. Cure structural non-shrink grout per manufacturer’s 

recommendation.

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1. Contact the manufacturer’s representative for advice on how 

to reduce heat such as wet curing or adding retarding 

admixture if the heat of hydration is excessive.

K. Repair or refund at the Department’s option any bonding failures 

that occur during the warranty period.

L. Finish grout flush or a maximum of 1⁄8 inch above adjacent panels.

1. Correct blockout and void profiles in excess of 1⁄8 inch higher 

than the adjacent panel through surface grinding

2. Correct blockout and void profiles below the top of the 

adjacent panels through removal and replacement of the 

blockout or void.

3. Pay for any corrections to the finish of the blockout or void at 

no cost to the Department.

3.7 DECK GRINDING

A. Profile grind the deck and approaches after all panels are in place, 

grouting is complete, and design strength is achieved according to 

Section 02982.

3.8 SURFACE PREPARATION

A. Prepare deck and approach slabs and place Polymer Overlay, 

Type 1. Refer to Section 03372.

END OF SECTION

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Example Specification C3:

Source: Utah Department of Transportation

Title: Bridge Construction using Self-Propelled Modular Transporters 

(SPMT) 

Use: SPMT Bridge Moves 

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June 25, 2009

SPECIAL PROVISION

PROJECT #

PIN #

SECTION 03253S

BRIDGE CONSTRUCTION USING SELF-PROPELLED 

MODULAR TRANSPORTERS (SPMT)

Add Section 03253:

PART 1 GENERAL

1.1 SECTION INCLUDES

A. Calculations, shop detail drawings, manuals, and engineering data 

addressing bridge movement

B. Confirm structural stress

C. Execution of bridge movement

D. Monitoring of bridge movement 

E. Post-movement inspection and remedial action 

1.2 RELATED SECTIONS

A. Section 03310: Structural Concrete 

1.3 REFERENCES

A. AASHTO Guide Design Specifications for Bridge Temporary 

Works, 1st Edition, 2008 Interim Revisions

 

B. AASHTO LRFD Bridge Construction Specifications, 2nd Edition, 

2004, 2008 Interim Revisions 

C. UDOT Manual for the Moving of Utah Bridges with Self Propelled 

Modular Transporters (SPMTs)

D. UDOT Minimum Sampling and Testing Requirements Manual

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1.4 DEFINITIONS

A. Change in Longitudinal Gradient Along the Girders – The change in 

slope experienced along the edge girders from conditions just 

before first lifting to any time during transportation.

B. Change in Transverse Gradient Across the Girder Span – The 

change in slope experienced along the end diaphragms from 

conditions just before first lifting to any time during transportation. 

C. Definitions and terminology used with SPMT systems - Refer to 

UDOT Manual for the Moving of Utah Bridges with Self Propelled 

Modular Transporters (UDOT SPMT Manual).

D. Twist – The maximum allowable upward or downward deflection of 

one corner relative to the plane defined concurrently by the 

elevations of the other three corners. 

1.5 SUBMITTALS

A. Submit a schedule addressing the timing and sequence of 

fabrication and erection of the permanent substructure and 

superstructure, removal or demolition of the old structure, 

construction of temporary abutments, connections with the 

roadway, road closures, and the transportation of the 

superstructure.

B. Submit working drawings for Engineer approval prior to ordering 

materials or commencing related work.

1. Engineer reserves the right to review these drawings for up 

to five working days without granting an increase in the 

number of working days for the project.

a. This right applies each time drawings are submitted.

2. Bridge Staging Area (BSA) and Travel Path (TP). 

a. Indicate all ground improvements, soft soil mitigation, 

 and utility protection. 

b. Verify clearances from above ground obstacles and 

 provide mitigation. 

3. Selected movement system.

a. Design the movement system to lift the bridge at the 

 pick points indicated in the project plans.

b. Demonstrate that the new pick points support the 

structure within the stress limits indicated on the 

project plans when lifting the bridge at pick points 

other than those indicated on the design.

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c. Design the lifting system to provide wheel loads equal 

to or less than those indicated on the project plans.

d. Indicate that the selected lifting system will possess 

adequate stroke to negotiate the TP as designed.

e. Indicate any additional systems required to move the 

structure, for example such items may include skid 

shoes, climbing jacks, and strand jacks.

1) Demonstrate that stresses provided in the 

project plans are not exceeded. 

f. Provide pre-operations checklist.

4. SPMT Support Apparatus 

a. Design SPMT Supports to meet AASHTO Guide 

Design Specifications for Bridge Temporary Works, 

1st Edition, 2008 Interim Revisions and 2nd edition 

2004 AASHTO LRFD Bridge Construction 

Specifications, 2008 interim revisions.

b. Calculate the anticipated lateral forces due to for 

example braking, turning, and vertical grades and 

provide a system to transfer loads to SPMTs.

5. Temporary abutments 

a. Refer to Section 03310.

b. AASHTO Guide Design Specifications for Bridge 

Temporary Works, 1st Edition, 2008 Interim 

Revisions. 

 6. QA/QC procedures

C. Submit elected changes to project plans in the form of shop 

drawings stamped by a professional engineer licensed in the State 

of Utah.

1. Submit all shop drawings to the Engineer electronically in 11 

inch X 17 inch format with the Department project 

designation data, drawing number, and sheet number in the 

lower right hand corner. 

2. Changes to BSA and TP

a. Submit VE proposals for changes to BSA and TP.

b. Provide design of BSA and TP meeting criteria in 

 UDOT SMPT Manual.

3. Changes to Pick-Points

a. If elected pick points cause stresses exceeding those 

allowed in the project plans, redesign bridge at 

Contractor’s expense. 

b. Identify additional project plans affected by the 

redesign of the structure.

c. Provide a redesign of any project plans affected by

the redesign of the structure.

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D. Provide MOT plan and schedule.

E. Contingency plans. 

1.6 ACCEPTANCE

A. Acceptance is in accordance with UDOT Minimum Sampling and 

Testing Requirements.

PART 2 PRODUCTS

2.1 BRIDGE CONSTRUCTION USING MOVEMENT SYSTEMS

A. Provide all materials for the permanent features of the project in 

conformance with UDOT specifications.

B. Provide all temporary features of the project suitable to sustain 

applied forces.

C. Provide satisfactory replacement material at no additional expense 

to the Department.

D. Contact the Engineer for qualified product information.

Part 3 EXECUTION

3.1 PREPARATION FOR TRANSPORT OF SUPERSTRUCTURE

A. Follow established and submitted QC/QA procedures.

B. Follow Pre-Operations checklist.

C. Obtain Engineers approval for all temporary Traffic Control Plans 

(TCPs) and Traffic Operational procedures prior to transportation.

D. Implement traffic control prior to transportation.

E. Do not exceed the SPMT ground pressures for the supporting 

capacity of the soil, roadway construction, or any structures over 

which the load will travel.

F. Follow approved working drawings for the positioning of the 

SPMTs.

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G. Follow specified allowable limits for loss of support by any pair of 

wheels or axle lines. 

H. Implement contingency plans in the event of a major breakdown of 

equipment to complete the installation with minimal disruption or 

delay to traffic.

3.2 LIFT, TRANSPORT, AND PLACEMENT OF SUPERSTRUCTURE

A. General

1. Check elevations of bearing seats and tops of bearings prior 

to lifting bridge.

a. Notify the Engineer of differences between as-built 

and as-planned bearing elevation and submit 

proposals for corrective adjustments.

2. Lift and transport structure in accordance with the lifting 

points established in the drawings.

3. Deliver the structure to its final location with no damage or 

loss of strength, performance, or long-term durability.

B. Monitoring

1. Monitor the span for stability and integrity of the SPMT 

system during lifting, transport, and placement following the 

plans for the equipments and methods of monitoring.

2. Monitor deflection and twist control during transportation.

3. Obtain deflection and twist tolerances from the Engineer.

4. Provide measurements to the Engineer for actual deflection 

and twist during lift, transport, and setting.

5. Halt operations immediately if deflection or twist exceed 

allowable limits as designed by the Engineer, returning 

bridge to temporary supports if necessary.

C. Tolerances

1. Plan alignment, location, and clearances for the final 

condition of the span after placement.

2. Do not exceed 2 inches for spans under 100 ft, and 3 inches 

for spans over 100 ft at each end of the span for maximum 

deviation from overall longitudinal alignment of an individual 

span after setting.

3. Do not exceed 2 inches for spans under 100 ft, and 3 inches 

for spans over 100 ft for maximum deviation from the overall 

transverse location at each line of bearing.

4. Do not exceed 2 inches for spans under 100 ff, and 3 inches 

for spans over 100 ft for maximum yaw.

5. Maintain individual elements or surfaces within 2 inches for 

spans under 100 ft, and 3 inches for spans over 100 ft of 

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location with respect to similar matching surfaces at 

expansion joints (plane of web parapet) of adjacent spans, 

pier or abutment features in the absence of other 

constraints.

6. Provide the maximum allowable change in longitudinal 

gradient. along the girders.

a. Calculate change from differences between the 

elevations taken just before lifting and the elevations 

taken at any time during transport.

7. Provide the maximum allowable change in transverse 

gradient across the girder span.

a. Calculate change from differences between the 

elevations taken just before lifting and the elevations 

taken at any time during transport.

END OF SECTION

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Example Specification C4:

Source: Utah Department of Transportation

Title: Structural Concrete - Lightweight 

Use: Lightweight concrete for reducing weight of prefabricated

elements 

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September 22, 2009

SPECIAL PROVISION

PROJECT #

PIN #

SECTION 03314S

STRUCTURAL CONCRETE - LIGHTWEIGHT

Add Section 03314:

PART 1 GENERAL 

1.1 SECTION INCLUDES

A. Materials and procedures for producing Portland cement concrete 

using lightweight aggregate for the coarse portion of the mix.

B. Materials and procedures for constructing structural concrete, 

including box culverts, diversion boxes, catch basins, cleanout 

boxes and other items as specified.

1.2 RELATED SECTIONS

A. Section 03055: Portland Cement Concrete

B. Section 03211: Reinforcing Steel and Welded Wire

C. Section 03310: Structural Concrete

D. Section 03390: Concrete Curing

1.3 REFERENCES

A. AASHTO M 6: Fine Aggregate for Portland Cement Concrete

B. AASHTO M 195: Lightweight Aggregates for Structural Concrete

C. AASHTO T 104: Soundness of Aggregate by Use of Sodium 

Sulfate or Magnesium Sulfate 

D. AASHTO T 121: Density (Unit Weight), Yield, and Air Content 

(Gravimetric) of Concrete

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E. AASHTO T 196: Air Content of Freshly Mixed Concrete by the 

Volumetric Method

F. ASTM C 567: Standard Test Method for Determining Density of 

Structural Lightweight Concrete

G. UDOT Materials Manual of Instruction

H. UDOT Minimum Sampling and Testing Requirements

I. UDOT Quality Management Plans

 

1.4 DEFINITIONS

A. Structural Concrete – Lightweight – a concrete mixture with all 

attributes equal to structural concrete with exception to weight. 

Weight is limited to a maximum of 120 lb/ft3

. 

1.5 SUBMITTALS

A. Furnish to the Resident Engineer and Region Materials Engineer a 

mix design based on the recommendations of the lightweight 

aggregate manufacturer for each combination of materials to be 

used.

1. Mix designs will be approved based on results of trial 

batches or on history from UDOT projects within the last 

year. 

2. Use the same components in the trial batches that are to be 

used in the project.

a) Accelerators and site-added air-entrainment can be 

incorporated in the trial batch but are not required.

b) Assume responsibility for the compatibility of all 

admixtures with the mix design and their potential 

effects on concrete properties.

3. List the weight and absolute volume for each component to 

be used.

4. Provide certified test reports showing the unit weight of fresh 

concrete that will result in the air-dry unit weight specified.

5. Personnel performing and witnessing trial batches, and 

performing compressive and flexural strength testing, must 

be UDOT TTQP Concrete and Concrete Strength Testing 

qualified.

6. The Department or its representative may witness the trial 

batch.

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7. Mix concrete trial batches as specified in UDOT Materials 

Manual of Instruction Part 8-974: Guidelines for Portland 

Cement Concrete Mix Design. 

8. Compressive and flexural strength testing for verification of 

trial batches will be performed by an AASHTO accredited 

laboratory, approved through the UDOT Laboratory 

Qualification Program.

B. Provide test results verifying the coarse and fine aggregate used 

meets this Section, article 2.3.

C. Provide test results for potential reactivity of fine aggregates in 

accordance with the requirements of the UDOT Quality 

Management Plan for Ready-Mix Concrete for any proposed mix 

design.

D. Provide results from appropriate testing to determine the ability of 

the combinations of cementitious materials and aggregates to 

control the reactivity when using potentially reactive aggregates in a 

mix design.

E. Submit verification that cement used is from a pre-qualified 

supplier. See Section 03055.

F. Submit verification that fly ash or other pozzolan used is from a prequalified supplier. See Section 03055.

G. Submit verification that the batch plant meets the requirements of the 

UDOT Quality Management Plan for Ready-Mix Concrete.

H. Submit cold and hot weather plans as required in Section 03055.

1.6 ACCEPTANCE

A. Refer to Section 03055.

B. Acceptance is in accordance with UDOT Minimum Sampling and 

Testing Requirements with the following exception:

1. Air content will be determined by AASHTO T 196

2. Density of fresh concrete with each air content 

determination. Refer to AASHTO T 121.

PART 2 PRODUCTS

2.1 MIX REQUIREMENTS

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A. Class AA(AE) concrete, unless specified otherwise. Refer to 

Section 03055

B. Keep the air-dry unit weight of the mix between 2950 to 3100 lb/ 

yd3. 

1. Determine the air-dry weight in accordance with ASTM C 

567.

C. Do not allow the fresh concrete to vary more than ± 110 lb/yd3 from 

that shown on the mix design.

2.2 CEMENT

A. Refer to Section 03055.

2.3 AGGREGATES

A. Coarse Aggregate

1. Use lightweight aggregates that are rotary kiln expanded 

shale or clay having a surface sealed by firing.

a. Do not crush coarse aggregate after firing except that 

a small amount of aggregate, 3⁄4 inch or smaller, may 

be crushed to the extent necessary to produce the 

required coarse aggregate grading.

b. Use coarse aggregate of 3⁄4 inch maximum.

2. Meet the requirements of AASHTO M 195.

a. Meet Table 1, gradation band 12.5 to 4.75 mm (1⁄2 

inch to #4) or 19.0 to 4.75 mm (3⁄4 inch to #4)

3. Use lightweight aggregates that have not more than 5 

percent loss, when tested for soundness using Magnesium 

Sulfate (5 cycles). Refer to AASHTO T 104.

B. Fine Aggregate

1. Refer to Section 03055

2.4 WATER

A. Refer to Section 03055.

2.5 ADMIXTURES

A. Refer to Section 03055.

2.6 POZZOLAN

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A. Refer to Section 03055.

2.7 REINFORCING STEEL AND WELDED WIRE

A. Refer to Section 03311.

2.8 JOINTS AND SEALERS

A. Refer to Section 03310.

2.9 BACKER ROD

A. Refer to Section 03310.

2.10 WATERSTOPS 

A. Refer to Section 03310.

2.11 RIGID PLASTIC FOAM

A. Refer to Section 03310.

2.12 CURING COMPOUND

A. Refer to Section 03390.

2.13 FORMS 

A. Refer to Section 03310.

2.14 MISCELLANEOUS STEEL ITEMS 

A. Refer to Section 03310.

PART 3 EXECUTION

3.1 PREPARATION - CONCRETE

A. Aggregate Stockpiles 

1. Refer to Section 03055.

2. Uniformly pre-wet or pre-saturate the aggregates in such a 

manner that uniform penetration of the concrete will be 

maintained. 

a. Pumping of the concrete requires pre-saturation of the 

lightweight aggregate.

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Federal Highway Administration Accelerated Bridge Construction Manual 

3.2 BATCH MATERIALS

A. Refer to section 03055.

B. Batch lightweight coarse aggregate either by weight or by volume. 

If by volume, equip the batching equipment such that the weight of 

each size of aggregate in the batch can be verified. 

C. Do not allow the fresh concrete to vary more than ± 110 lb/yd3 from 

that shown submitted with the mix design. 

1. Verify each load using batched weights of materials. 

3.3 MIX DESIGN

A. Design mixes to meet the requirements of this Section and project 

specific criteria.

B. Design the cementitious system to mitigate potential alkaliaggregate reactivity.

1. Use a minimum of 20 percent by weight of the total 

cementitious system when using fly ash.

C. Use only concrete mixes that have been approved by the Region 

Materials Engineer.

D. Obtain concurrence from the Resident Engineer for the project 

specific application of an approved mix

3.4 PREPARATION – PLACEMENT 

A. Refer to Section 03310.

3.5 GIRDERS SLABS AND COLUMNS

A. Refer to Section 03310.

3.6 BOX CULVERTS

A. Refer to Section 03310.

3.7 PLACE CONCRETE

A. Refer to Section 03310.

3.8 PUMP CONCRETE

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A. Refer to Section 03310.

3.9 LIMITATIONS – GENERAL

A. Refer to Section 03055.

3.10 LIMITATIONS – COLD WEATHER

A. Refer to Section 03310.

3.11 LIMITATIONS – HOT WEATHER

A. Refer to Section 03310.

3.12 CYLINDER STORAGE DEVICE

A. Refer to Section 03055.

END OF SECTION

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Example Specification C5:

Source: Massachusetts Department of Transportation

Title: High Early Strength Concrete 

Use: Concrete for closure pours used in ABC 

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ITEM 904.XX HIGH EARLY CUBIC YARD 

STRENGTH CONCRETE

The work to be done under this item shall conform to the relevant provisions of Section 

901 of the Standard Specifications and the following:

The Contractor shall develop a high early strength concrete mix design for use in the 

longitudinal and transverse closure pours. This high early strength concrete may also be 

used in the cast in place concrete work for the modifications to the approach slabs. 

The high early strength concrete shall conform to the requirements of M4.00.00, M4.01. 

and M4.02. and the following criteria:

1. Use Portland cement conforming to AASHTO M 85 with compatible admixtures 

and air entraining agent.

2. Water-cementitious material ratio shall not exceed 0.4 by weight, including water 

in the admixture solution and based on saturated surface dry condition of 

aggregates. 

3. Use a maximum size coarse aggregate of 3⁄4”. 

4. The amount of entrained air shall be 6.0 +/- 1.5%. 

5. A slump test shall be developed as part of the QC plan and shall address 

changing environmental conditions. 

6. High early strength concrete shall achieve a minimum compressive strength of 

2,000 psi at 4 hours after the final set. The minimum 28-day compressive 

strength shall be 4000 psi. 

7. A shrinkage reducing admixture shall be added to the concrete mix according to 

the manufacturer’s recommendation such that there will be no cracks at 14 days 

in the sample tested in AASHTO T334 (see below). A shrinkage reducing 

admixture shall be tested by an approved testing lab and meet the requirements 

of ASTM C494-10 Type S, except that in Table 1 length change shall be 

measured as: Length Change (percent of control) shall be a minimum of 35% 

less than that of the control. Table 1 Length Change (increase over control) shall 

not apply. Shrinkage reducing admixtures shall not contain expansive metallic 

materials.

8. The maximum allowable total chloride content in concrete shall not exceed 0.1% 

by weight of cement.

Mix Design Requirements

The concrete mix design shall be mitigated per Subsection M4.02.00. Proposed mix 

design (overdesign factor of 120% of the design strength) with data sheets and trial 

batches shall be submitted within 15 days from the date of Notice to Proceed to the 

Research and Materials Section for review and approval. The Engineer shall be notified 

at least 48 hours prior to the test batching and shall be present to witness the testing. 

All tests necessary to demonstrate the adequacy of the concrete mix shall be performed 

by the Contractor, including, but not limited to: slump, air content, temperature, initial set 

and final set (AASHTO T197). Compressive strength tests shall be determined on field 

cured cylinders (6” X 12” cylinders) at 9 hours, 12 hours, 15 hours, 18 hours, 24 hours, 

30 hours, 36 hours, 42 hours, 2 days and 3 days, and standard cured cylinders at 7 days 

and 28 days. Additionally, a confined shrinkage test as outlined in the AASHTO T334 - 

Practice for Estimating the Crack Tendency of Concrete shall be performed by an 

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AASHTO accredited laboratory. The results of these tests (documenting zero cracks at 

14 days) shall be submitted to the Engineer.

Field Trial Placement

In addition, a trial placement shall be done a minimum of (90) ninety days before the 

intended date of the initial closure pour placement. The Contractor will be required to 

demonstrate proper mix design, batching, placement, finishing and curing of the high 

early strength concrete. The trial placement shall simulate the actual job conditions in all 

respects including plant conditions, transit equipment, travel conditions, admixtures, 

forming, the use of bonding compounds, restraint of adjacent concrete, placement 

equipment, and personnel. 

The details for the trial placement configuration are shown in Figure 1.

Acceptance criteria for the trial placement shall be as follows:

• The trial placement concrete shall not exhibit cracking or separation from the test 

panel in excess of 0.016 inches wide

• There shall be no more than one transverse crack in excess of 0.010 inches wide 

in the 10 foot long pour. 

• The evaluation of the trial placement shall take place 14 days after placement. 

If the trial placement fails these criteria, the Contractor will be required to submit a 

corrective action plan on how repairs of these crack sizes will be performed. The 

Engineer may require the Contractor to conduct more trial batches and trial placements. 

The costs of trial batches, trial placements and the removal of trial placement concrete 

from the job site is incidental to Item 904.XX. The requirement for multiple test 

placements shall not be cause for a time extension. 

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Field Testing of Concrete Mix during Construction

The Contractor shall engage an AASHTO accredited laboratory to provide on-site mobile 

testing facilities which are qualified laboratories under the NETTCP program to perform 

all Quality Control field testing. All personnel performing tests shall be qualified NETTCP 

Concrete Technicians and certified ACI Concrete Laboratory Technicians. Anytime the 

Contractor moves the laboratory, all associated equipment shall be recalibrated. The 

onsite laboratories should be located and calibrated at each bridge location. On 

weekends where more than one bridge is being constructed, additional on site 

laboratories shall be provided so that there is one for each bridge being constructed. 

This requirement is intended to minimize the movement of test cylinders.

The Contractor is required to perform initial set and final set tests (AASHTO T197) in 

addition to slump, air content and temperature on concrete from each concrete truck 

used in the placing of this High Early Strength Concrete. Field cured cylinders (6” X 12” 

cylinders) will be made from the first and last concrete trucks. A set of three (3) fieldcured cylinders shall be made for each informational test associated with early structural 

loading. The Contractor is advised to fabricate adequate sets of cylinders to allow 

multiple tests to verify field concrete strength. The Engineer shall be allowed to witness 

the test and comment on all the tests performed by the Contractor. The Contractor must 

have a contingency plan established and approved in case compressive strength and 

other requirements are not met. The Contractor shall not open the roadway to traffic until 

all of the following conditions have been met:

• At least four hours has elapsed from the last final set time recorded for any 

concrete. Final set is achieved when the penetration resistance measures 4000 

psi by AASHTO T197.

• Field cured cylinder breaks have achieved at least 2000 psi.

• The Engineer has directed that the roadway can be opened to traffic.

All testing and equipment shall conform to AASHTO T-22, and the making and curing of 

concrete cylinders shall conform to AASHTO T23. All costs associated with the on-site 

mobile testing facilities, personnel and field testing, equipment calibration and 

verification to demonstrate the field concrete strength shall be incidental to Item 904.XX.

Verification tests will be performed by MassDOT on field cured cylinders at 3 days and 

on standard cured cylinders at 7 days and 28 days. Cylinder breaks at 3 days and 7 

days must be at least 10% above the approved trial batch results. The Contractor will be 

notified of any verification tests that do not meet these requirements and will be required 

to develop a contingency corrective action plan incase final strength is not achieved. 

Concrete will be accepted based on meeting the 28-day strength requirement of 4000 

psi.

Curing Methods

The concrete curing methods shall be developed by the Contractor as part of the QC 

plan. The curing methods used in the production placements shall be the same as the 

curing methods used for the trial placement.

High Early Strength Concrete Crack Inspection

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The Contractor shall inspect the finished high early strength concrete surface for cracks. 

Inspection of the deck for cracking shall be completed after the 14 day cure and prior to 

the preparation of the deck for placement of the membrane waterproofing system. 

The Contractor shall document the location and frequency of cracks on the closure 

pours (number of cracks per square foot). Cracks greater than 0.016 inches in width 

shall be repaired as required by the membrane waterproofing manufacturer. The 

Contractor shall develop repair procedures as part of the QC plan. 

The work completed under this Item will be paid for at the contract price per actual 

number of cubic yards of high early strength concrete that is measured complete in 

place. Payment under this Item includes full compensation for all testing and approval of 

the mix design. 

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