The Implementation of Full 

Depth UHPC Waffle Bridge 

Deck Panels

Final Report 

Publication No. FHWA-HIF-13-031 

May 2013 
Notice

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

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the information contained in this document. 

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manufacturers' names appear in this report only because they are considered essential to the 

objective of the document. 

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Technical Report Documentation Page 

1. Report No. 

FHWA-HIF-13-031

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

4. Title and Subtitle 

The Implementation of Full Depth UHPC Waffle Bridge 

Deck Panels: Final Report 

5. Report Date 

May 2013

6. Performing Organization Code 

7. Author(s) 

John Heimann 

8. Performing Organization Report No. 

9. Performing Organization Name and Address 

Coreslab Structures (Omaha), Inc. 

802 Allied Rd. 

Bellevue, NE 68123 

10. Work Unit No. (TRAIS) 

11. Contract or Grant No. 

DTFH61-09-G-00006 

12. Sponsoring Agency Name and Address 

Federal Highway Administration 

Highways for LIFE Program – HIHL-1 

1200 New Jersey Avenue, SE 

Washington, D.C. 20590

13. Type of Report and Period Covered 

Final report, 6/15/2009 – 1/31/2013

14. Sponsoring Agency Code 

15. Supplementary Notes 

16. Abstract 

In the U.S. today, there are over 160,000 bridges that are structurally deficient or obsolete, and more than 3,000 

new bridges are added each year. Federal, State, and municipal bridge engineers are seeking new ways to build 

better bridges, reduce travel times, and improve repair techniques, thereby reducing maintenance. Additionally, 

owners are challenged with replacing critical bridge components, particularly bridge decks, during limited or 

overnight road closure periods. 

State and Federal agencies are gaining significant interest in using full depth ultra high performance concrete 

(UHPC) waffle deck panels as a possible solution to these challenges. The first implementation of UHPC deck 

panels on a U.S. roadway was made possible through a grant from the Federal Highway Administration’s 

Highways for LIFE program. The objective of this research is to confirm that this system is a viable solution to 

the problems encountered by design engineers. It is hoped that the full depth UHPC bridge deck system will 

revolutionize the way bridges are designed in North America. 

This project was divided into two phases. Phase 1 included the design and testing of a mock-up bridge section 

for verifying design assumptions, as well as for evaluating the feasibility of manufacturing and installing the deck 

elements. Phase 2 consisted of the construction of a full scale two-lane bridge on a secondary road in Wapello 

County, Iowa, using prestressed concrete girders and 14 UHPC deck panels. 

17. Key Words 

UHPC, Waffle Slab, Bridge Deck, Highways for 

LIFE 

18. Distribution Statement 

No restrictions. This document is available to the public 

through the National Technical Information Service, 

Springfield, VA 22161.

19. Security Classification (of this report) 

Unclassified

20. Security Classification (of this page)

Unclassified

21. No. of Pages 

66 

22. Price

FORM DOT F 1700.7 (8-72) REPRODUCTION OF COMPLETED PAGE AUTHORIZED 
ii 
iii 

TABLE OF CONTENTS 

1. INTRODUCTION ................................................................................................................... 1

2. WORK COMPLETED IN PHASE 1 ...................................................................................... 3

WAFFLE PANEL DESIGN AND FABRICATION ................................................................. 3

LABORATORY LOAD TESTING ........................................................................................... 7

CONCLUSIONS....................................................................................................................... 10

3. WORK COMPLETED IN PHASE 2 .................................................................................... 11

WAFFLE PANEL DESIGN ..................................................................................................... 11

DEMONSTRATION PROJECT PANEL FABRICATION .................................................... 19

DEMONSTRATION PROJECT CONSTRUCTION .............................................................. 23

IN-SITU TESTING AND EVALUATION .............................................................................. 28

4. LIFE CYCLE COST ANALYSIS ......................................................................................... 31

LCCA ASSUMPTIONS AND SUMMARY OF RESULTS ................................................... 31

CONCLUSIONS....................................................................................................................... 34

5. REFERENCES ...................................................................................................................... 36

APPENDIX: PLANS FOR LITTLE CEDAR CREEK BRIDGE, WAPELLO COUNTY, IA 

 
iv 

LIST OF FIGURES 

Figure 1. Diagram. Shop drawing of prototype panel. ................................................................... 3

Figure 2. Photo. Prototype panel form setup. ................................................................................. 4

Figure 3. Photo. Casting.................................................................................................................. 5

Figure 4. Photo. Placing the voids as they are lowered into position. ............................................ 5

Figure 5. Photo. Formwork removed. ............................................................................................. 6

Figure 6. Photo. Completed prototype panels. ................................................................................ 7

Figure 7. Photo. SRV testing setup. ................................................................................................ 9

Figure 8. Diagram. Final panel dimensions. ................................................................................. 13

Figure 9. Diagram. Final panel reinforcing. ................................................................................. 13

Figure 10. Photo. Casting bed and side forms. ............................................................................. 15

Figure 11. Photo. Void form. ........................................................................................................ 15

Figure 12. Photo. Flow table. ........................................................................................................ 17

Figure 13. Graph. Time vs. temperature. ...................................................................................... 18

Figure 14. Photo. Initial form setup. ............................................................................................. 19

Figure 15. Photo. Placing UHPC. ................................................................................................. 20

Figure 16. Photo. UHPC placed to correct level. .......................................................................... 20

Figure 17. Photo. Placing the voids. ............................................................................................. 21

Figure 18. Photo. Formwork removed (panel upside down). ....................................................... 21

Figure 19. Photo. Lifting the panel to vertical. ............................................................................. 22

Figure 20. Photo. Panel rotated back to horizontal (panel right side up). ..................................... 23

Figure 21. Diagram. Plan of the demonstration bridge. ................................................................ 24

Figure 22. Diagram. Cross section of the demonstration bridge. ................................................. 24

Figure 23. Photo. Setting the deck panels. .................................................................................... 25

Figure 24. Photo. Close view of the deck panels. ......................................................................... 26

Figure 25. Photo. Portable mixers for batching joint fill UHPC. ................................................. 27

Figure 26. Photo. Transverse joint casting. ................................................................................... 27

Figure 27. Photo. Completed demonstration bridge. .................................................................... 28

Figure 28. Diagram. Locations of monitored panels. ................................................................... 29

Figure 29. Equation. LCCA formula. ........................................................................................... 31

Figure 30. Diagram. Bridge plans, page 1. ................................................................................... 38

Figure 31. Diagram. Bridge plans, page 2. ................................................................................... 39

Figure 32. Diagram. Bridge plans, page 3. ................................................................................... 40

Figure 33. Diagram. Bridge plans, page 4. ................................................................................... 41

Figure 34. Diagram. Bridge plans, page 5. ................................................................................... 42

Figure 35. Diagram. Bridge plans, page 6. ................................................................................... 43

Figure 36. Diagram. Bridge plans, page 7. ................................................................................... 44

Figure 37. Diagram. Bridge plans, page 8. ................................................................................... 45

Figure 38. Diagram. Bridge plans, page 9. ................................................................................... 46

Figure 39. Diagram. Bridge plans, page 10. ................................................................................. 47

Figure 40. Diagram. Bridge plans, page 11. ................................................................................. 48

Figure 41. Diagram. Bridge plans, page 12. ................................................................................. 49

Figure 42. Diagram. Bridge plans, page 13. ................................................................................. 50

Figure 43. Diagram. Bridge plans, page 14. ................................................................................. 51
v 

Figure 44. Diagram. Bridge plans, page 15. ................................................................................. 52

Figure 45. Diagram. Bridge plans, page 16. ................................................................................. 53

Figure 46. Diagram. Bridge plans, page 17. ................................................................................. 54

Figure 47. Diagram. Bridge plans, page 18. ................................................................................. 55

Figure 48. Diagram. Bridge plans, page 19. ................................................................................. 56

Figure 49. Diagram. Bridge plans, page 20. ................................................................................. 57

Figure 50. Diagram. Bridge plans, page 21. ................................................................................. 58

Figure 51. Diagram. Bridge plans, page 22. ................................................................................. 59

LIST OF TABLES 

Table 1. Structural test protocols and sequence. ............................................................................. 8

Table 2. Sand patch test results. ...................................................................................................... 9

Table 3. Skid resistance test results. ............................................................................................. 10

Table 4. User costs for the demonstration bridge and the CIP bridge. ......................................... 32

Table 5. LCCA summary: demonstration bridge. ......................................................................... 33

Table 6. LCCA summary: CIP bridge. ......................................................................................... 33

LIST OF ACRONYMS AND ABBREVIATIONS 

AASHTO American Association of State Highway and Transportation Officials 

BPN British Pendulum Number 

BPT British Pendulum Tester 

CIP Cast-in-Place 

DOT Department of Transportation 

FEA Finite Element Analysis 

FHWA Federal Highway Administration 

LCCA Life Cycle Cost Analysis 

LRFD Load and Resistance Factor Design 

PPE Personal Protective Equipment 

SRV Skid Resistance Value 

TRRL Transport and Road Research Laboratory 

UHPC Ultra High Performance Concrete 

 
vi 
1 

1. INTRODUCTION 

In the U.S. today, there are over 160,000 bridges that are structurally deficient or obsolete, and 

more than 3,000 new bridges are added each year.(1) Federal, State and municipal bridge 

engineers are seeking new ways to build better bridges, reduce travel times, and improve repair 

techniques, thereby reducing maintenance. Additionally, owners are challenged with replacing 

critical bridge components, particularly bridge decks, during limited or overnight road closure 

periods. 

In response to these challenges, researchers at the Federal Highway Administration (FHWA) 

Turner-Fairbank Highway Research Center began investigating potential solutions in 2000. 

Prototype designs of full depth ultra high performance concrete (UHPC) waffle deck panel 

systems have been in development over the past 6 years in both Europe and the U.S. 

UHPC provides superior durability against chlorides, freeze-thaw effects, salt scaling, abrasion, 

accidental impact, fatigue, and overload, thereby extending the useful life of the bridge deck. 

Combining these positive attributes of UHPC and the efficiency of the waffle panel design 

provides an extremely durable option that enables faster construction and longer girder spans 

through the efficient use of materials and reduced weight. In addition to these benefits, the 

UHPC waffle panel bridge deck system is applicable to both new construction and the 

rehabilitation of existing deteriorated bridge decks. Using this solution for bridge rehabilitation 

not only restores the deck but also provides opportunities for upgrading load capacity through the 

improved strength and reduced deck dead load.

Numerous State departments of transportation (DOT) and the FHWA have expressed significant 

interest in using full depth UHPC waffle deck panels. By demonstrating this system is a viable 

solution to the problems encountered by design engineers, it is hoped that it will revolutionize 

the way bridges are designed in North America. 

The research conducted under this project was divided into two phases. Phase 1 included the 

design and testing of a mock-up bridge section for verifying design assumptions, as well as 

evaluating the feasibility of manufacturing and installing the deck elements. Phase 2 consisted of 

the construction of a full scale two-lane bridge on a secondary road in Wapello County, Iowa, 

using prestressed concrete girders and 14 UHPC deck panels. This report describes the results of 

both Phase 1 and Phase 2. 
2 
3 

2. WORK COMPLETED IN PHASE 1 

This chapter summarizes the progress that was made in Phase 1 of the project. As mentioned 

previously, the objectives of Phase 1 were to prototype and model the demonstration bridge 

construction planned for Phase 2. These objectives were met by producing two prototype UHPC 

waffle deck panels based on preliminary design work completed by the Iowa DOT, modeling the 

section of the demonstration bridge that would undergo testing in Phase 1 using a finite element 

analysis (FEA) to predict the response of the system, and load testing the prototype waffle slabs 

to confirm the design assumptions and FEA validity. 

WAFFLE PANEL DESIGN AND FABRICATION 

The preliminary design of the waffle slab was completed in late August 2009, and shop drawings 

were completed by early September 2009. The project team consulted on the fabrication process 

and aspects of the design relating to ease of production and requirements for UHPC joint fill. 

The prototype panels were 8 feet wide by 9 feet, 9 inches long, with two layers of mild 

reinforcing in each rib and dowel bars extending out of the slab at the transverse panel-to-panel 

joint locations (see figure 1). The prototype panel modeled one girder-to-girder span along the 

length of the bridge. It was determined that two slabs would be necessary to test the transverse 

panel-to-panel joint. 

Figure 1. Diagram. Shop drawing of prototype panel.

The two prototype panels were produced in September 2009 at the Coreslab Structures plant in 

LaPlatte, NE. The panels were cast using a displacement technique where the form was first 

partially filled with fluid UHPC. Then the voids, which make the ribs of the panel, were forced 

downward into the UHPC to displace the material, creating the shape of the panel. This 
4 

technique was used to allow for the removal of the voids once the UHPC reached initial set, 

which is necessary to allow for unrestrained shrinkage and to maintain the random orientation 

and consistent meshing of the fiber reinforcement. An additional benefit of casting the panels in 

an inverted orientation is that the final driving surface will be cast into the panels through the use 

of a form liner. By eliminating the application of a wearing surface placed in the field, the cost of 

the system is further reduced, while the durability is increased. Figures 2 through 6 depict the 

casting and production sequence. 

Figure 2 shows the reinforcing layout of the first casting. Uncoated reinforcing was used because 

the UHPC is effectively impermeable, eliminating the need for epoxy coated, galvanized, or 

stainless steel reinforcing to resist corrosion. The prototype panel formwork was made of wood 

to provide an inexpensive and temporary form. This strategy was employed because the design 

was preliminary, and changes to the rib size, spacing, and joint profiles were possible between 

the prototype and demonstration panels. The final formwork will be made of steel and adjustable 

for various panel configurations. In addition to the standard reinforcing, several strain gauges 

were cast into the panels to monitor the internal responses of the UHPC and reinforcing. 

Figure 2. Photo. Prototype panel form setup.

Figure 3 shows the placing of the UHPC into the form. The UHPC was placed with a specially 

designed bucket that is the same width as the form, which aligns the steel fibers in the UHPC in 

the longest direction of the panel. This alignment helps to increase the flexural strength of the 

panels. The bucket was moved along the length of the form and kept behind the leading edge of 

the flow to eliminate any discontinuity in the fiber orientation. The form was filled to a 

predetermined level equal to the required volume of the panel, and then the voids were set as an 

assembly (see figure 4). Each of the prototype panels required approximately 1 cubic yard of 

UHPC. 
5 

Figure 3. Photo. Casting.

Figure 4. Photo. Placing the voids as they are lowered into position.

By placing the voids as an assembly, the panels can be cast substantially faster and with more 

precision. The UHPC is displaced by the voids as they are lowered into position to create the 

final shape of the piece. Placing the voids prior to the casting would create a cold joint effect at 

the corners of the voids because, as the UHPC flows into itself around the corners of the voids, 

the fibers will not cross the intersection of the two flows of UHPC. 
6 

As mentioned previously, this casting method also allows the voids to be removed after the 

initial set of the UHPC, which allows the UHPC to shrink without inducing internal stresses. 

This is important because the UHPC will reach initial set within 12 to 14 hours but will not reach 

release strength until approximately 40 hours after casting. Damage from shrinkage can occur 

during this time if the appropriate precautions are not taken. Figure 5 shows the panel after the 

side forms and voids were removed. 

Figure 5. Photo. Formwork removed.

After the panels reached the required 14,000 psi release strength, they were stripped from the 

form. The panels were lifted into the vertical position by the casting bed, rotated 180 degrees 

about a vertical axis, and lowered back to the horizontal position in the proper orientation by the 

casting bed. This technique was used to reduce the handling stresses on the panels. Even though 

the concrete strength is very high at release, the sections from which the panels are rotated are 

very thin, limiting the amount of stress that can be taken without cracking. The critical section is 

at the very thin area where the toe of the transverse joint edge and the longitudinal rib intersect. 

By rotating the piece with the casting bed, the issue of handling stresses is eliminated. 

The panels were moved to the curing area and exposed to an accelerated steam curing cycle for 

48 hours at 195 °F, as specified for maximum strength and durability. Before steam curing the 

panels measured approximately 15,000 psi compressive strength. A test cylinder was broken 

before the steam was turned off to verify that the panels had cured correctly, and the compressive 

strength of the UHPC at that time was 29,800 psi, exceeding the required design strength of 

24,000 psi. After curing was complete, the panels were loaded on a truck and transported to Iowa 

State University to be load tested. 
7 

Figure 6. Photo. Completed prototype panels. 

LABORATORY LOAD TESTING 

Laboratory load testing included testing the panels and the transverse joint in service, fatigue, 

and ultimate loading scenarios, along with investigating friction properties of textures for the 

driving surface. Table 1 shows the structural test protocols and sequence. The load magnitudes 

for testing were established using the American Association of State Highway and 

Transportation Officials (AASHTO) 16-kip service level truck wheel load with a factor of 1.33 

for the panel and 1.75 for the joint to account for impact from moving loads. 

To represent field conditions as closely as possible, it was determined that a prestressed concrete 

beam was needed to support the panels during testing. A beam similar to the one required for the 

demonstration bridge was used. 

A UHPC joint casting was required and completed in the laboratory. The transverse joint 

between the panels, the shear pockets, and the longitudinal area along the length of the support 

beam were cast with Ductal UHPC in late November 2009. The laboratory joint fill followed the 

same processes and used the same equipment as planned for the full scale demonstration bridge 

construction. 
8 

Table 1. Structural test protocols and sequence. 

Test 

Number Test Description Loading Location Maximum Load 

1 Service load test 

panel-2 Center of the panel 1.33a

 x 16kips = 

21.3 kips 

2 Service load test on 

transverse joint Center of the joint 1.75b

 x 16 kips = 

28 kips 

3 Fatigue test on the 

transverse Joint Center of the joint 28 kips (1 million 

cycles) 

4 Ultimate load test of 

transverse joint Center of the joint 48 kips 

5 Fatigue test on the 

panel-1 Center of the panel 21.3 kips (1 million 

cycles) 

6 Ultimate load test of 

the panel Center of the panel 40 kips 

a, b –dynamic allowance factors from AASHTO table 3.6.2.1-1(2)

Strength and Serviceability Testing 

An FEA model of the completed test setup was created, and several runs were made to locate the 

worst case loading scenarios before the physical testing began. This helped limit the amount of 

physical testing required and decrease the amount of time required for the testing phase of the 

project. It was verified upon completion of the testing that the model closely represented the 

results of the physical tests and will enable future projects incorporating UHPC to be designed 

and investigated more efficiently and with less physical testing. 

The results of the testing were promising. In summary, the 21.3-kip load placed on the panel 

caused two hairline cracks in the rib below the loading location, and the 28-kip load applied to 

the joint caused a barely visible crack to form on the bottom of the joint, as predicted by the FEA 

model. Fatigue loading applied for the specified 1,000,000 cycles did not have any noticeable 

effect on the strength or durability of the panels. 

Surface Texture and Skid Resistance Testing 

Five commercially available form liners were selected as possible driving surface textures, and 

12-inch by 12-inch samples of the textures were cast in UHPC. The samples were tested 

according to ASTM E303(3), Standard Method for Measuring Surface Friction Properties, and the 

Transport and Road Research Laboratory (TRRL, formerly the Road Research Laboratory) 

Standard Sand Patch Test for Measuring Surface Texture Depth (4). Table 2 summarizes the 

results of both tests. 

Any texture depth greater than 1/64 inch for the Standard Sand Patch Test is considered “open,” 

according to the TRRL. An open sample indicates the texture can be worn substantially from its 

current condition before becoming smooth, which means it has good characteristics for use as a 

long-term wearing surface. The testing showed all samples met the criteria to be classified as 

open. 
9 

Table 2. Sand patch test results. 

Sample 

No. 

Texture (Source) Sand Patch Dia. 

(in.) 

Average 

Dia. (in.) 

Texture 

Depth (in.) 

Texture 

Characterization 

1 2/61 Thames (Rekli) 9.45, 8.66, 8.46, 

8.86 

8.86 0.05 Open 

2 2/102 Parana (Rekli) 7.87, 7.68, 7.87, 

8.07 

7.87 0.04 Open 

3 Broom Finish 

(Architectural Polymers) 

10.04, 9.25, 9.65, 

9.06 

9.50 0.06 Open 

4 Heavy Broom 

(Architectural Polymers) 

6.30, 6.30, 6.10, 

5.90 

6.15 0.10 Open 

5 Anti-Skid 

(Fitzgerald Formliners) 

8.66, 8.86, 9.06, 

9.06 

8.87 0.05 Open 

Texture Depth = ସ௏

గௗమ ൈ 10ଷ, V = 3.051187 in3

The skid resistance value (SRV) was measured using a British Pendulum Tester (BPT), 

according to ASTM E303. The BPT is a dynamic pendulum impact-type tester used to measure 

the energy loss when a rubber slider edge is propelled over a test surface. The test was performed 

on the same set of sample textures as the Sand Patch Test, and four SRV tests were performed on 

each sample. The SRV test setup is shown in figure 7, and a summary of the SRV tests is 

presented in table 3. 

Figure 7. Photo. SRV testing setup. 

 
10 

Table 3. Skid resistance test results. 

Sample 

No.

Texture (Source) Skid Resistance 

Value (BPN) 

Average 

(BPN) 

1 2/61 Thames (Rekli) 87, 88, 88, 88 87.75 

2 2/102 Parana (Rekli) 96, 96, 96, 96 96 

3 Broom Finish 

(Architectural Polymers) 

72, 70, 70, 70 70.5 

4 Heavy Broom (Architectural 

Polymers) 

80, 81, 80, 81 80.5 

5 Anti-Skid 

(Fitzgerald Formliners) 

80, 80, 80, 81 80.25 

BPN = British Pendulum Number 

The suggested minimum SRV for difficult sites is 65, as determined by the TRRL, so all the 

tested textures are excellent choices for all possible scenarios and roadway types. Based on the 

information gathered from these tests, sample 2 was chosen due to its extremely high SRV and 

good surface texture characteristics. 

CONCLUSIONS 

The researchers developed a preliminary design that is anticipated to perform well in service. 

Casting was successful, and the prototype panels were produced without any major difficulties. 

An FEA was developed that accurately represented the material and the overall structural 

performance. 

Only minor cracking was observed during testing, and this amount of cracking is not anticipated 

to cause any long-term durability issues. 

A suitable wearing surface was selected. 

In general, the prototype panels performed very well and appeared to be more than capable of 

holding up to the rigors of use on a public highway. Additional information regarding the 

technical aspects of the strength and serviceability testing and associated results can be found in 

separate reports.(5,6) 
11 

3. WORK COMPLETED IN PHASE 2 

The objectives of Phase 2 included the construction of the full scale demonstration bridge in 

Wapello County and a life cycle cost analysis (LCCA). These objectives were met by producing 

14 UHPC waffle deck panels used in the demonstration bridge, creating an LCCA spreadsheet to 

compare the cost of conventional construction to the use of UHPC waffle deck panels over the 

useful life of the structure, and compiling data recorded during the first three months of the inservice performance of the demonstration bridge to determine the best estimation of the longterm performance and durability of the structure. 

WAFFLE PANEL DESIGN 

Research in the United States and Canada has shown that reinforced concrete bridge decks do 

not act as flexural members, but rather as low profile tied arches.(7) This research has noted the 

large factor of safety inherent in typically reinforced bridge decks. Factors from 8 to 10 are 

usually found with failures in typical decks by block shear and not flexure. Based on this study, 

bridge design specifications were developed in Ontario, Canada, in the early 1980s that allowed 

minimal reinforcing steel to be designed into bridge decks meeting required design conditions. (8)

In addition, AASHTO adopted similar design specifications with the release of the Load and 

Resistance Factor Design (LRFD) Bridge Design Specifications in 1994.(9) In the 1990s, the 

Iowa DOT constructed 16 bridges on the State’s primary system using the empirical deck design. 

The DOT’s bridge office has been monitoring these bridges since their construction. 

The preliminary design of the reinforcing steel for the waffle slab panels took into consideration 

the empirical design specifications allowed in the AASHTO LRFD Bridge Design 

Specifications. The empirical design allows for bridge decks that meet the required “9.7.2.4-

Design Conditions” to be designed using four layers of reinforcing steel with a minimum of: 

 0.27 in2/ft in the bottom mat of reinforcing. 

 0.18 in2

/ft in the top mat of reinforcing. 

In the preliminary design for the test panel, no. 7 reinforcing bars were used in the bottom mat of 

steel at a transverse spacing of 1 foot, 9.5 inches (0.334 in2

/ft) and longitudinal spacing of 2 feet, 

1 inch (0.28 in2

/ft). No. 6 reinforcing bars were used in the top mat at a transverse spacing of 1 

foot, 9.5 inches (0.246 in2/ft) and longitudinal spacing of 2 feet, 1 inch (0.211 in2/ft). 

The field cast UHPC joints were developed based on the testing done at the FHWA TurnerFairbank Highway Research Laboratory and the details used in New York and Canada on bridge 

projects that had already been completed.(10)

One other factor to note in the basic design was a limit of 8 inches of overall depth. This 

thickness was chosen to allow the UHPC waffle deck system to be used to replace existing 

deteriorated bridge decks without altering the road profile. 
12 

Initial discussion for the waffle panel design also included designing for a transversely pretensioned concrete section that would be longitudinally post-tensioned in the field to eliminate 

any cracks in the panels, but one goal from the producer’s view was to design the slabs with mild 

reinforcing. This decision would eliminate the need for prestressing capabilities in the precast 

plant, limiting the initial cost of the equipment and certification required to produce the slabs. 

Hopefully this decision will allow more producers and municipalities to adopt the UHPC waffle 

slab system. 

Once the basic design concept was completed, FEA was performed to assist in determining the 

adequacy of the panel. The FEA verified the design concept, with only minor cracking predicted 

at the bottom of the rib section, allowing the project to move to full scale testing. At this time it 

was decided that the connections between the panels would also need to be tested. The 

connection details were primarily based on ongoing testing at FHWA.(10) The locations for 

connection rebar dowels were limited based on the physical dimensions of the slab, so it was 

decided one reinforcing bar would be located at each rib of the panel in the transverse panel-to 

panel-joint, and two reinforcing bars would be placed in each rib of the panel at the longitudinal 

panel-to-panel joint in addition to the shear key detail on the panel edge. The acceptability of the 

panel-to-panel connections was primarily verified through testing. 

The project team reviewed the testing of the mock-up bridge section, and the final design of the 

waffle slab was completed in early April 2010. Shop drawings for use by production staff were 

complete shortly thereafter. Figures 8 and 9 show the final panel dimensions and reinforcing, 

respectively. 

The demonstration bridge panels were designed identically to the prototype panels with respect 

to the shape, depth, and spacing of the ribs and voids, but changes were made to the overall size, 

reinforcing design, and surface texture. The demonstration bridge panels were designed to span 

from the centerline of the roadway to the outside of the guardrail with an overall size of feet wide 

by 16 feet, 2.5 inches long. A no. 7 reinforcing bar was used in both the top and bottom of each 

rib instead of one no. 6 and one no. 7, to eliminate possible confusion and improper installation 

by the production staff. A section of reinforcing was also added to the outside edge of the panel 

to splice into the barrier posts that resist the impact forces from a vehicle collision. The 2/102 

Parana formliner texture selected from the skid resistance testing in Phase 1 was provided on the 

top surface of the panel to act as the final driving and wearing surface. 
13 

Figure 8. Diagram. Final panel dimensions. 

 Figure 9. Diagram. Final panel reinforcing. 
14 

TESTING EQUIPMENT AND PLANT MODIFICATIONS 

Special equipment is required to produce the waffle slabs and to mix, cast, cure, and test the 

UHPC. Most of the plant modifications required to accommodate the casting of UHPC were 

completed during Phase 1, including the basic formwork, UHPC mixing and placing equipment, 

and quality control and testing equipment. The additional modifications that were required to 

cast the demonstration slabs included the additional formwork used to cast the ribs and voids of 

the panels, and a computer controlled steam curing system. The equipment necessary to produce 

the UHPC waffle slabs is described in the sections below. 

Formwork 

No existing formwork matched the profiles of the waffle slab design or the edge conditions 

needed for the panel-to-panel joints. New formwork was designed and fabricated to cast the 

slabs. At the time of the prototype casting, the final design was unknown because testing would 

be required to validate the design. By researching the typical bridge designs in the Iowa highway 

system, it was determined that the maximum length would be 25 feet. The slab design was far 

enough along at the time of prototype casting to determine that the standard width would be 8 

feet. The width was chosen primarily due to transportation and handling restrictions. The casting 

bed was fabricated by a specialized formwork manufacturer to accommodate these dimensions 

and was utilized to rotate the prototype waffle slabs manufactured in Phase 1. As previously 

mentioned, the side and void forms for Phase 1 were fabricated out of wood to serve as a 

temporary form in the event changes to the section needed to be made between Phase 1 and 

Phase 2. 

The remaining formwork for the demonstration slabs was purchased after the final panel design 

was complete and was fabricated out of steel to allow for a high number of reuses and to 

conform to the tight tolerances required due to the thin UHPC sections used. The formwork 

consisted of a bottom form including the side forms, end forms, and the casting table acquired in 

Phase 1, and a top form which created ribs and voids of the panel. Figures 10 and 11 show the 

bottom and top form assemblies, respectively. 

The formwork was selected primarily to cast the demonstration panels but was also designed to 

be adaptable to various rib spacings and overall panel configurations for future uses of the waffle 

panel system. As shown in figure 11, the pans can be removed and replaced with different sizes 

on the transverse beams, and the transverse beam locations can be adjusted along the length of 

the longitudinal beams to accommodate unlimited configurations with a limited additional 

investment. The bottom form is also designed to cast a deck panel up to approximately 25 feet in 

length to accommodate panels covering multiple lanes of traffic. 
15 

Figure 10. Photo. Casting bed and side forms. 

Figure 11. Photo. Void form.

Casting and Initial Curing Equipment 

A high shear mixer is required to adequately mix the UHPC material, and most precast plants 

have an existing batch plant capable of mixing UHPC without major modifications. However, 

typically the capacity of the mixer is reduced by approximately 50 percent due to the amount of 

energy required to mix the UHPC. During both the Phase 1 and Phase 2 production periods, no 

modifications were made to the batch plant to add steel fibers to the mixer or to automate the 

addition of premix bags or admixtures. All components of the mix were weighed and added 

manually for this project. 
16 

The manual addition of steel fibers and other components of the UHPC mixture required 

additional safety precautions and personal protective equipment (PPE) beyond what is required 

for conventional concrete production. The most difficult problem to solve was how to protect 

workers from the steel fibers. A very durable and puncture-resistant glove is needed to handle the 

fibers. The best solution found was to use a thick rubber glove (to help prevent punctures) under 

a heavy welding glove (to provide a thick layer of protection). 

To place the UHPC in the forms, a concrete bucket was purchased in Phase 1. As mentioned 

previously, the bucket helped to create the alignment of the steel fibers, but it was also necessary 

because of the fluidity of the UHPC mix. Rubber gaskets were provided on the bucket gate to 

seal the opening. Previous experience with UHPC showed this was the only efficient way to 

transport UHPC from the mixer to the casting bed. 

UHPC needs to be moist cured during the initial curing period, but steam curing was not 

available at the casting bed, so dry heat and moisture retention was used. To cure the panels, the 

exposed surfaces were covered with a shrink wrap film in Phase 1 and spray applied liquid 

curing compound in Phase 2 to seal in the internal moisture. Heat was applied by propane heaters 

for the initial curing period, and the entire form was enclosed with a tarp to contain as much heat 

and moisture as possible. 

Quality Control Equipment 

Equipment for testing fresh UHPC was purchased before the prototype panel casting and 

included a flow table (see figure 12), vibrating table, molds for prisms and cylinders, and scales. 

These items were essential for producing a high-quality product. Project personnel were trained 

on the equipment and related procedures before production began. A cylinder end grinder and 

high capacity compression testing machine are needed to accurately verify compressive strength 

of cured UHPC. Since this equipment was outside the budget limitations for this project, a local 

university was contracted to perform the testing of the hardened properties within the 

specifications outlined by the supplier. 
17 

Figure 12. Photo. Flow table. 

Steam Curing 

To accelerate the curing process and increase the durability of the UHPC a 48-hour steam curing 

cycle is required. During Phase 1, the steam temperature was controlled manually by adjusting a 

ball valve approximately every 15 minutes. This process was inefficient and time-consuming, but 

it was effective in reaching the required design strength for the mock-up panels. An automated 

steam curing system was purchased to provide precise control and eliminate the constant 

monitoring and manual adjustment of the temperature for the demonstration panels. A Sure Cure 

system consisting of a software package, electronic equipment, and thermocouples was used to 

monitor the internal temperature of the curing enclosure and control the steam flow into the 

curing enclosure by the use of an electronically actuated valve. The software package also logs 

the time and temperature curve for the curing cycle to assist with quality control. See figure 13 

for an example of the output. Two channels of temperature recording are shown in magenta and 

orange, and one channel of ambient temperature is shown in black. 
18 

Figure 13. Graph. Time vs. temperature. 

Other Plant Modifications 

Additional equipment and plant modifications were considered in the original proposal, 

including a fiber distribution system for mixing UHPC, the installation of an automated bed heat 

system to cure the fresh UHPC, construction and installation of a permanent steam curing 

chamber, and the purchase of special equipment to handle the slabs from the edges. Knowledge 

gained during the course of the project proved that these items were not required and did not 

prove to be cost-effective for this project alone. Commercial fabrication of UHPC may warrant 

the purchase of these items based on the volume of product required. 

Impact on the Precaster 

In general, the modifications required to produce the UHPC waffle deck panels were very 

limited, and for small quantities of UHPC production, no modifications to the plant would be 

required beyond formwork. If more than one or two castings are required, it is recommended to 

invest in the products purchased for this project, including a bucket, testing equipment, and a 

curing system to improve the efficiency and safety of the operation. The process and timing 

related to producing UHPC compared to conventional concrete is the biggest change to the 

production environment. Once a process is implemented and a new mindset of the crew 

producing the panels is reached, the process runs smoothly. 

 
19 

DEMONSTRATION PROJECT PANEL FABRICATION 

The demonstration project panels were produced with the same basic process as the prototype 

panels. Figure 14 shows the form setup for the first demonstration panel casting. Uncoated 

reinforcing was used on the demonstration panels because only very minor cracking on the 

bottom surface of the panel was observed during the laboratory testing of the prototype panels. 

However, the dowels entering the field cast joints were made of stainless steel to provide an 

additional factor of safety against the possibility of corrosion at the interface between the plant 

and field cast UHPC. Unlike the prototype panels, no monitoring instruments were cast into the 

panels. 

Figure 14. Photo. Initial form setup.

Figure 15 shows the placing of the UHPC into the form. The UHPC was placed with the same 

specially designed bucket that was used for the prototype panels. Along with being able to 

transport the extremely fluid material, the bucket helps to align the steel fibers in the UHPC in 

the longest direction of the panel. The bucket was moved along the length of the form and kept 

behind the leading edge of the flow to eliminate any discontinuity in the fiber orientation. 

The form was filled to a predetermined level based on the total volume of UHPC required for a 

panel, and then the voids were set as an assembly (see figures 16 and 17). Each of the prototype 

panels required approximately 2 cubic yards of UHPC. By placing the voids as an assembly, the 

panels can be cast quickly while keeping the size and spacing of the ribs very accurate. As with 

the prototype panels, the UHPC is displaced by the voids as they are lowered into position to 

create the final shape of the piece. 

 
20 

Figure 15. Photo. Placing UHPC. 

Figure 16. Photo. UHPC placed to correct level.
21 

Figure 17. Photo. Placing the voids.

As mentioned previously, by forming the panels upside down and using a displacement casting 

method, the voids can be removed after the initial set of the UHPC, which allows the UHPC to 

shrink unrestrained. Damage from shrinkage will occur between initial set and stripping if the 

appropriate precautions are not taken. The use of steel forms increased the need to remove the 

voids promptly because the form was extremely rigid compared to the prototype panel form 

made of wood and foam. Using the displacement technique also helps to randomly orient the 

fibers in the rib sections. Figure 18 shows the panel after the formwork is removed. 

Figure 18. Photo. Formwork removed (panel upside down).
22 

After the required 14,000 psi release strength was verified, the panels were lifted into the vertical 

position by the casting bed (see figure 19), rotated 180 degrees about a vertical axis, and lowered 

back to the horizontal position in the proper orientation by the casting bed similar to the 

prototype panels (see figure 20). The panels were then moved from the casting area to the curing 

area. 

Checking the release strength was one of the challenges faced by the plant when dealing with 

UHPC. A 3-inch by 6-inch cylinder with 14,000 psi compressive strength could be tested at the 

precast plant using existing compression machine, but the ends of the cylinders could not be 

prepared to the flatness tolerance outlined in the specifications. The cylinders were ground flat 

by hand, not by a machine, so the compressive strength measured was most likely a conservative 

value due to stress concentrations on the cylinder ends caused by unevenness. The alternative to 

this conservative method was to deliver individual cylinders to the local university and have 

them tested every time release strength needed to be verified, but this was not feasible due to 

time constraints in the production schedule. 

Figure 19. Photo. Lifting the panel to vertical.
23 

Figure 20. Photo. Panel rotated back to horizontal (panel right side up).

The panels were cured for 48 hours at 195 F, as required by the supplier for maximum strength 

and durability. Prior to steam curing, the panels measured approximately 15,000 psi compressive 

strength. A series of test cylinders were broken after the steam curing was completed to verify 

that the panels had been cured correctly, and the compressive strength of the UHPC at that time 

was an average of 33,700 psi, substantially exceeding the required design strength of 24,000 psi. 

After curing was complete, the panels were stored until they were needed at the demonstration 

bridge job site. 

DEMONSTRATION PROJECT CONSTRUCTION 

The demonstration bridge in Wapello County is 33 feet, 2 inches wide by 60 feet long, consisting 

of 14 UHPC panels supported on five Iowa “B” beam precast/prestressed concrete girders spaced 

at 7 feet, 4 inches, with overhangs measuring 1 foot, 11 inches. The panels are jointed with 

UHPC at the crown longitudinally, the transverse panel-to-panel joints, and the shear pockets 

over the girders. The demonstration bridge plan and cross section are shown in figures 21 and 22, 

respectively. 

The design of the demonstration bridge and deck panels was completed in early April 2010; 

however, due to an extraordinary amount of rainfall and flood damage around the bridge site, the 

construction schedule was delayed by approximately 1 year. The letting for the general 

contractor occurred in May 2011, and construction began in August 2011. A full set of plans for 

the demonstration bridge, including the panels and connections, is included in the appendix. 

The general contractor proceeded with construction quickly. The existing bridge was removed 

the week of August 15, 2011, and new substructure and abutments were completed by September 
24 

5, 2011. The precast beams and UHPC panels were set in place starting the week of September 

12, 2011, followed by the approach slabs and other associated road work. The total time to install 

the bridge was less than 4 months. 

Figure 21. Diagram. Plan of the demonstration bridge. 

Figure 22. Diagram. Cross section of the demonstration bridge.
25 

Panel Installation 

The panels were delivered by truck to the demonstration bridge site, where they were offloaded 

and stacked until they were needed. The panels were set over a period of 2 days, and simple 

slings were used for rigging. The sequence of installation was from south to north on the east 

side and from north to south on the west side, due to the layout of the reinforcing dowels. Steel 

shims were placed under the panels to align the top surface of the panels and provide a smooth 

driving surface. Two layers of half-inch compressible foam weather stripping were placed along 

the top surface of the beams to seal the gap between the beams and panels to contain the field 

cast UHPC placed in the longitudinal panel joint and shear pockets. Figure 23 shows the deck 

panels being set, and figure 24 shows a close-up of the panels in place. 

The contractor had no major problems installing the panels, and the east side of the bridge was 

completed in only a few hours since each panel’s transverse joint dowel bars were designed to 

set on top of the previous panel’s dowel bars. The only minor issue was the installation of the 

second panel on the west side of the bridge. The panel was difficult to install because of the 

overlapping reinforcing dowels in both the transverse and longitudinal joints, but after a few 

adjustments to the rigging, the contractor was able to slide the panel into position. The same 

rigging technique was used for the remaining panels on the west side of the bridge without any 

issues. 

Figure 23. Photo. Setting the deck panels.
26 

Figure 24. Photo. Close view of the deck panels.

Joint Fill 

The field cast UHPC joints were poured on September 27 and 28, 2011. The transverse panel-topanel joints on the east side were cast on September 27, and the transverse panel-to-panel joints 

on the west side, along with the longitudinal crown joint, were cast on September 28. The UHPC 

was mixed on-site with two portable mixers. Approximately 222 feet of joint were cast on 

September 27, and 282 feet were cast on September 28. The UHPC was placed using 

wheelbarrows and a funnel system. Figures 25 and 26 illustrate the construction sequence of 

filling the joints and shear pockets with UHPC. 

The transverse panel-to-panel joints were set tight together, but they were also sealed with a bead 

of silicone caulking to ensure no UHPC leaked out of the joint during casting. The longitudinal 

joint and the shear pockets were sealed with the weather stripping applied to the beams during 

construction. Weather stripping was also applied to the top side of the panels at all field cast 

locations to act as a form extension and ensure there were no areas of the joint that were 

underfilled. 
27 

Figure 25. Photo. Portable mixers for batching joint fill UHPC.

Figure 26. Photo. Transverse joint casting.

A layer of sealed plywood was placed over the weather stripping at the joints and shear pockets 

after they were filled with UHPC to prevent moisture loss during the curing period. Small risers 

were placed on each joint and filled with UHPC to provide positive fluid pressure on the joints to 

Riser used to maintain fluid 

pressure on the joint fill.
28 

force air out of the mix and keep the joint completely filled. Sandbags were placed on top of the 

plywood to keep the UHPC from leaking out of the joints and onto the deck due to the pressure 

from the riser and the bridge slope. 

According to the supplier, casting went very well. If it had not rained the day before casting 

delaying form preparation, the entire joint fill process could have been finished within an 8-hour 

work day. The contractor was also very easy to work with and was open to suggestions relating 

to the joint fill process. The only negative of the joint fill was one low spot in the UHPC on the 

first day of casting. The imperfection was noticed prior to casting the second day, and two layers 

of weather stripping were used instead of the single layer used on the first day. 

Figure 27 is a photograph of the completed demonstration bridge. 

Figure 27. Photo. Completed demonstration bridge. 

IN-SITU TESTING AND EVALUATION 

Field testing was used to evaluate the performance of the UHPC waffle deck panels under true 

service conditions. The demonstration bridge was opened to traffic in November 2011 and field 

tested in February 2012. The field testing included monitoring of live load deflections and 

deformations at discrete, critical locations on the bridge superstructure as it was subjected to 

static and dynamic truck loads. A 3D FEA of the bridge was used to help interpret the results of 

live load testing, estimate strains due to dead load, and examine live load distribution. 

Two UHPC waffle deck panels along the length of the bridge were selected for instrumentation. 

One of these panels was located near the mid-span, and the other was located adjacent to the 

south abutment, as illustrated in figure 28. Surface-mounted strain gauges were used on each 
29 

panel and their adjacent UHPC joints to quantify deformations and identify the likelihood of 

cracking under service loads. The locations of these strain gauges were selected to coincide with 

critical locations on the panels and deck joints where stress and strain would likely be extreme. 

Figure 28. Diagram. Locations of monitored panels. 

In addition to the strain gauges on the deck panels, 13 surface-mounted strain gauges and five 

string potentiometers were attached to the girders to characterize the global bridge behavior, 

measure mid-span deflections, and quantify lateral live load distribution factors. Using two 

additional string potentiometers, deflections were also measured at the mid-spans of the deck 

panel located near the center of the bridge. Top and bottom girder strains were also monitored 

for three of the girders at mid-span and at a section 2 feet from the south abutment. 

Live load was applied by driving a heavily loaded dump truck across the bridge along 

predetermined paths. The total weight of truck was 60,200 lb, with a front axle weight of 18,150 

lb and two rear axles weighing roughly 21,000 lb each. For static tests, the truck was driven 

across the bridge at a speed of less than 5 miles per hour. Each load path was traversed twice to 

ensure repeatability of the measured bridge response. For dynamic tests, the truck speed was 

increased to 30 miles per hour to examine dynamic amplification effects. 

The results of the testing were promising. The maximum strains and deflections experienced by 

the demonstration bridge during the field tests were well within expected performance 

parameters. No strains recorded on the top of the deck indicated a likelihood of cracking or 

opening of joint interfaces that might adversely affect durability. The only locations where 

strains approached the anticipated cracking threshold of the UHPC waffle deck were on the 
30 

underside of the panel adjacent to the abutment. These cracks were small in width, and the 

strains recorded during the test were less than those recorded on the laboratory test panels at 

service load levels. 

In general, the UHPC waffle deck panels performed very well and appear to be more than 

capable of holding up to the rigors of use on a public highway. 

Additional details of the Phase 2 field testing are expected to be published in the 2013 

proceedings of the PCI Convention and National Bridge Conference (E.H. Gheitanbaf, J.M. 

Rouse, and S. Sritharan, authors).

 
31 

4. LIFE CYCLE COST ANALYSIS 

LCCA was performed to compare the demonstration bridge to a conventional cast-in-place (CIP) 

concrete deck bridge of the same size that would be typical for the location of the demonstration 

bridge. The following sections summarize the methodology and assumptions used to complete 

the analysis, along with a summary of the results. 

LCCA ASSUMPTIONS AND SUMMARY OF RESULTS 

The formula in figure 29 was used to calculate the LCCA for both options: 

Figure 29. Equation. LCCA formula.

Where: 

FC = First (Initial) Cost 

t = Time Period of Analysis 

MC = Maintenance Costs 

IC = Inspection Costs 

FRC = Future Rehabilitation Costs 

S = Salvage Values or Costs 

pwf = Present Worth Factor 

UC = Users Costs 

The life cycle cost consists of the summation of all costs incurred over the life of the structure 

discounted to account for the use of constant dollars. These costs include the initial design and 

construction costs, periodic maintenance and inspection costs, future rehabilitation costs, any 

residual value or salvage value, and the user costs associated with all of the previously 

mentioned activities. The discount rate is represented by the present worth factor, and for this 

analysis a value of 3 percent was used (typical established values range from 3 to 5 percent). All 

costs for the LCCA were gathered from actual costs recorded during the demonstration project 

construction or best professional estimates by the Iowa DOT, Wapello County, or the contractor. 

The user costs for both options were compiled using the information shown in table 4, and a 

spreadsheet prepared by the Pennsylvania DOT available for public use was modified and used 

to complete the computations. 

LCCA summaries for the demonstration bridge and the CIP option are shown in tables 5 and 6, 

respectively. The LCCA for both options turned out to be similar after all costs were considered. 

                                                                                                                         t=n

LCC = FC +  pwf [MC+IC+FRC+UC] + pwf [S]                                                                                                                     t=0
32 

Table 4. User costs for the demonstration bridge and the CIP bridge. 

User Cost Inputs 

Demonstration 

Bridge 

CIP Bridge 

Length of affected roadway (miles)* 3.00 3.00 

Average Daily Traffic* 280 280 

Normal traffic speed (mph) 45 45

Construction traffic speed (mph) 45 45 

Normal accident rate (per million vehicle miles) 1.9 1.9

Construction accident rate (per million vehicle miles) 2.2 2.2

Number of construction days 120 130

*Total traffic affected by maintenance, inspection, and rehabilitation activity. 

As shown in tables 5 and 6, the CIP bridge has a slightly lower life cycle cost than the 

demonstration bridge. There are a few main causes: 

 The initial cost of the demonstration bridge is high. A large initial cost is difficult to 

overcome and is the biggest cause for uncertainty about UHPC. If the initial cost for the 

UHPC option could be decreased, the LCCA would favor this option easily. 

 The amount of traffic using the bridge is relatively small. The user costs associated 

with maintaining and rehabilitating the CIP bridge are one of the main reasons the LCCA 

is close to being equal for both options. However, the amount of traffic using the bridge 

on a rural secondary road is considerably less than what would be found on a highway or 

interstate. If this bridge were placed on a road with double the daily traffic, the LCCA 

would favor the demonstration bridge. 

 The maintenance and rehabilitation costs for the CIP bridge occur far enough in the 

future that the costs are discounted substantially to convert to today’s dollar value. 

While the CIP bridge requires considerably more maintenance than the demonstration 

bridge, the costs occur at 25, 50, and 100 years in the future. Due to the discount rate, 

these costs are reduced to a small value in terms of today’s dollars. This limits the effect 

of maintenance costs in the overall LCCA. 

Based on the results of the LCCA, it appears the UHPC waffle deck system would be ideally 

suited for use on a heavily traveled road where impacts to users would be minimized by the 

shorter construction time and decreased maintenance activity. 

 
33 

Table 5. LCCA 

summary: 

demonstration bridge. 

Table 6. LCCA 

summary: CIP bridge. COST NOTES $498,017 Actual Recorded Cost of Construction (Provided by Wapello County) $175 / Year Estimated Yearly General Maintenance (Provided by Wapello County) $250 / Occurance Estimated Inspection Cost (Provided by Wapello County) $0 This Item is Not Needed on UHPC Bridge Crack Repair, Patching, Joint Sealant (Inspect / Repair / Replace) $0 This Item is Not Needed on UHPC Bridge Surface Grinding and Overlay $0 This Item is Not Needed on UHPC Bridge Redeck Bridge $0 This Item is Not Needed on UHPC Bridge Surface Grinding and Overlay $0 This Item is Not Needed on UHPC Bridge Demolish and Rebuild CIP Bridge $0 Assume girder life is extended by 20 years due to fewer deck rehabilitations End of Usefull Life - No Residual Value and less damage from corrosion due to poor deck conditions. User Costs Associated with Construction and Maintenance $168,702 (Calculated from data provided by IDOT) Accident Costs Consists of Driver Delay Costs, Vehicle Operating Costs, and TOTAL LIFE CYCLE COST $680,270 120 Year UHPC Design Life Reached 100 Year CIP Design Life Reached 75 Year Scheduled Maintenance Demonstration Bridge 50 Year Scheduled Maintenance 25 Year Scheduled Maintenance ITEM Inspections Annual Maintenance Initial Cost (Required Every Two Years) Five Year Increment Scheduled Maintenance COST NOTES $375,642 Estimated Cost of Construction with Typical CIP Deck Design (Provided by Wapello County / IDOT) $250 / Year Estimated Yearly General Maintenance (Assume slightly more than UHPC) (Provided by Wapello County) $200 / Occurance Estimated Inspection Cost (Assume slightly less than UHPC) (Provided by Wapello County) $1,000 / Occurance Crack Repair, Patching, Joint Sealant (Inspect / Repair / Replace) $25,000 (Provided by IDOT) Surface Grinding and Overlay $45,000 (Provided by IDOT) Redeck Bridge $25,000 (Provided by IDOT) Surface Grinding and Overlay $375,642 Assumed Typical Service Life of CIP Bridge is 100 Years Demolish and Rebuild CIP Bridge $0 Not Applicable to the CIP Bridge 120 Year Residual Value of CIP Bridge $297,313 Credit for 80 years of useful life remaining in the structure (Calculate from construction cost - future maintenance costs) User Costs Associated with Construction and Maintenance $233,824 (Calculated from data provided by IDOT) Accident Costs Consists of Driver Delay Costs, Vehicle Operating Costs, and TOTAL LIFE CYCLE COST $662,756 120 Year UHPC Design Life Reached 100 Year CIP Design Life Reached 75 Year Scheduled Maintenance Inspections Annual Maintenance (Required Every Two Years) 50 Year Scheduled Maintenance 25 Year Scheduled Maintenance Five Year Increment Scheduled Maintenance Estimated Cost of a Similar Bridge with CIP Deck ITEM Initial Cost
34 

CONCLUSIONS 

The final design is anticipated to perform well in service. 

Casting was a successful experience for Coreslab Structures. The demonstration bridge panels 

were produced with ease due to the experience of Phase 1. 

Construction of the demonstration bridge proceeded smoothly, considering the new construction 

techniques that were required. 

The testing on the completed structure validates the assumptions from Phase 1 testing. 

Only minor cracking was observed adjacent to the abutment in the demonstration bridge that 

poses no threat to the long-term durability of the structure. 

The LCCA relating to the UHPC waffle deck system is suited for a roadway where user costs 

can be decreased by construction speed and reduced maintenance delays. 

Overall, the project has been a successful experience, and invaluable knowledge has been gained 

relating to the application of UHPC in bridge construction. 
35 
36 

5. REFERENCES 

1. U.S. Department of Transportation, “Analysis of an Ultra-High Performance Concrete TwoWay Ribbed Bridge Deck Slab,” FHWA TechBrief, Publication No. FHWA-HRT-07-055, 

Turner-Fairbank Highway Research Center, McLean, VA, 2007. 

2. American Association of State Highway and Transportation Officials, AASHTO LRFD 

Bridge Design Specifications, 4th ed., AASHTO, Washington, D.C., 2007. 

3. ASTM International, “Standard Test Method for Measuring Surface Frictional Properties 

Using the British Pendulum Tester,” Standard No. E303-93, ASTM Annual Book of 

Standards Volume 04.03, Road and Paving Materials, ASTM, West Conshohocken, PA, 

2008. 

4. Road Research Laboratory, Ministry of Transport, Instructions for Using the Portable Skid 

Resistance Tester, 2nd ed., Road Note 27, Her Majesty’s Stationery Office (HMSO), London, 

UK, 1969. 

5. Aaleti, S., S. Sritharan, D. Bierwagen, and T. J. Wipf, “Structural Behavior of Waffle Bridge 

Deck Panels and Connections of Precast Ultra-High-Performance Concrete: Experimental 

Evaluation,” Transportation Research Record No. 2251, Transportation Research Board of 

the National Academies, Washington, D.C., 2011, pp. 82-92. 

6. Aaleti, S., S. Sritharan, M. Rouse, and T. Wipf, “Structural Characterization of UHPC Waffle 

Bridge Deck Panels and Connections,” published as Appendix A in The Implementation of 

Full Depth UHPC Waffle Bridge Deck Panels, Phase 1 Report, by J. Heimann & G. Schuler, 

2010. Available on the FHWA website at 

http://www.fhwa.dot.gov/hfl/partnerships/coreslab/phase1/app_index.cfm. 

7. Taylor, S. E., B. Rankin, D. J. Cleland, and J. Kirkpatrick, “Serviceability of Bridge Deck 

Slabs with Arching Action,” ACI Structural Journal, volume 104, no. 1, 2007, pp. 39-48. 

8. Graddy, J. C., J. Kim, J. H. Whitt, N. H. Burns, and R. E. Klingner, “Punching-Shear 

Behavior of Bridge Decks under Fatigue Loading,” ACI Structural Journal, volume 99, no. 

3, 2002, pp. 257-266. 

9. American Association of State Highway Transportation Officials, AASHTO LRFD Bridge 

Specifications, 1st ed., AASHTO, Washington, D.C., 1994. 

10. Perry, V. H., P. Scalzo, and G. Weiss, “Innovative Field Cast UHPC Joints for Precast Deck 

Panel Bridge Superstructures – CN Overhead Bridge at Rainy Lake, Ontario,” Proceedings 

of the National Bridge Conference, Precast/Prestressed Concrete Institute (PCI), Chicago, IL, 

2007. 

 
37 
38 

APPENDIX: PLANS FOR LITTLE CEDAR CREEK BRIDGE, WAPELLO COUNTY, IA 

Figures 30 through 51 are the complete set of plans for the Little Cedar Creek Bridge. 

Figure 30. Diagram. Bridge plans, page 1. 
39 

Figure 31. Diagram. Bridge plans, page 2. 
40 

Figure 32. Diagram. Bridge plans, page 3. 
41 

Figure 33. Diagram. Bridge plans, page 4. 
42 

Figure 34. Diagram. Bridge plans, page 5. 
43 

Figure 35. Diagram. Bridge plans, page 6. 
44 

Figure 36. Diagram. Bridge plans, page 7. 
45 

Figure 37. Diagram. Bridge plans, page 8. 
46 

Figure 38. Diagram. Bridge plans, page 9. 
47 

Figure 39. Diagram. Bridge plans, page 10. 
48 

Figure 40. Diagram. Bridge plans, page 11. 
49 

Figure 41. Diagram. Bridge plans, page 12. 
50 

Figure 42. Diagram. Bridge plans, page 13. 
51 

Figure 43. Diagram. Bridge plans, page 14. 
52 

Figure 44. Diagram. Bridge plans, page 15. 
53 

Figure 45. Diagram. Bridge plans, page 16. 
54 

Figure 46. Diagram. Bridge plans, page 17. 
55 

Figure 47. Diagram. Bridge plans, page 18. 
56 

Figure 48. Diagram. Bridge plans, page 19. 
57 

Figure 49. Diagram. Bridge plans, page 20. 
58 

Figure 50. Diagram. Bridge plans, page 21. 
59 

Figure 51. Diagram. Bridge plans, page 22.