Research, Development, and Technology

Turner-Fairbank Highway Research Center

6300 Georgetown Pike

McLean, VA 22101-2296

PUBLICATION NO. FHWA-HRT-24-011 JANUARY 2024

FHWA Bridge Preservation 

Research Roadmap
FOREWORD

In recent years, State departments of transportation (DOTs) have established bridge preservation 

programs and made significant progress in bridge preservation practice and research. More 

bridge preservation technologies, planning strategies, and tools have been investigated and 

adopted to extend the service life and restore serviceability of existing bridges. The concept of 

using high-performance and durable materials, low-maintenance structure types, and details to 

extend the maintenance-free service life of new construction has become more widely accepted. 

In addition, developments in data technologies have enhanced data-driven performance 

evaluation, risk-based decisionmaking, and lifecycle analysis capabilities. As more bridges in 

poor condition are replaced, proactive bridge preservation is becoming increasingly important to 

maintain bridge inventories in states of good repair in a cost-effective way. 

In 2008, the Federal Highway Administration (FHWA) collaborated with the American 

Association of State Highway and Transportation Officials (AASHTO) Transportation System 

Preservation Technical Services Program and the Transportation Research Board to develop the 

Transportation System Preservation Research, Development, and Implementation Roadmap.(1)

Significant advances in bridge preservation prompted FHWA to produce an updated research 

roadmap reflecting the progress made and identifying current research gaps. This update was 

developed by examining publications and research led by FHWA, State DOTs, and AASHTO 

from 2010 to 2022 to assess accomplishments and remaining gaps. Additional research gaps 

were also identified that support FHWA initiatives in sustainability, infrastructure resilience, risk 

evaluation, digital twins, and data integration related to bridge preservation and management. 

This roadmap is intended for use primarily by FHWA. Other agencies or organizations may also 

use the roadmap in selecting and funding research in bridge preservation programs. 

Jean A. Nehme, Ph.D., P.E. 

Director, Office of Infrastructure

Research and Development

Notice

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

(USDOT) in the interest of information exchange. The U.S. Government assumes no liability for 

the use of the information contained in this document.

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. 

Quality Assurance Statement

The Federal Highway Administration (FHWA) provides high-quality information to serve 

Government, industry, and the public in a manner that promotes public understanding. Standards 

and policies are used to ensure and maximize the quality, objectivity, utility, and integrity of its 

information. FHWA periodically reviews quality issues and adjusts its programs and processes to 

ensure continuous quality improvement.
TECHNICAL REPORT DOCUMENTATION PAGE

1. Report No.

FHWA-HRT-24-011

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

4. Title and Subtitle

FHWA Bridge Preservation Research Roadmap

5. Report Date

January 2024

6. Performing Organization Code:

7. Author

Ping Lu (ORCID: 0000-0002-9427-2415)

8. Performing Organization Report No.

9. Performing Organization Name and Address

Office of Infrastructure Research and Development

Federal Highway Administration

6300 Georgetown Pike

McLean, VA 22101-2296

10. Work Unit No.

11. Contract or Grant No.

12. Sponsoring Agency Name and Address

Office of Infrastructure Research and Development

Federal Highway Administration

6300 Georgetown Pike

McLean, VA 22101-2296

13. Type of Report and Period Covered

Final Report 

14. Sponsoring Agency Code

HRDI-20

15. Supplementary Notes

This research project was led by the Federal Highway Administration’s Office of Infrastructure Research and 

Development. The point of contact was Ping Lu (HRDI-20; ORCID: 0000-0002-9427-2415).

16. Abstract

Since the publication of the Transportation System Preservation Research, Development, and Implementation 

Roadmap in 2008, most State departments of transportation (DOTs) have established bridge preservation programs 

and have made significant progress in the areas of bridge preservation practice and research.(1) State DOTs have 

investigated, developed, and used bridge preservation technologies, materials, planning strategies, and tools to 

extend the service life and restore the serviceability of existing bridges. The use of high-performance materials and 

low-maintenance structure types and details to extend the maintenance-free service life of new construction has 

become more widely accepted. In recent years, developments in data technologies have enhanced data-driven 

performance evaluation, risk-based decisionmaking, and lifecycle analysis capabilities. As more bridges in poor 

condition are replaced, proactive bridge preservation is becoming increasingly important to cost-effectively maintain 

bridge inventories in states of good repair. Considering the advances mentioned, the 2008 roadmap needs to be 

reevaluated to determine whether those gaps are still valid and identify new ones. The author reviewed publications 

and research led by the Federal Highway Administration (FHWA), State DOTs, and the American Association of 

State Highway and Transportation Officials (AASHTO) from 2010 to 2022 to assess accomplishments and 

remaining gaps. Additional gaps were also identified to support FHWA initiatives in sustainability, infrastructure

resilience, risk evaluation, and big data as they relate to bridge preservation and management. The author also 

investigated FHWA initiatives in climate change, infrastructure resilience, and big data related to bridge 

preservation to identify new gaps. This roadmap is intended for use primarily by FHWA. Other agencies or 

organizations may also use the roadmap in selecting and funding research in bridge preservation programs.

17. Key Words

Bridge preservation, bridge preservation 

technologies, materials, data-driven, risk-based 

planning, lifecycle analysis, LCCA, resilience

18. Distribution Statement

No restrictions. This document is available to the public 

through the National Technical Information Service, 

Springfield, VA 22161.

https://www.ntis.gov.

19. Security Classif. (of this report)

Unclassified

20. Security Classif. (of this page)

Unclassified

21. No. of Pages

72 

22. Price

N/A

Form DOT F 1700.7 (8-72) Reproduction of completed page authorized.
ii

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 
iii

TABLE OF CONTENTS

EXECUTIVE SUMMARY .......................................................................................................... 1

CHAPTER 1. BACKGROUND................................................................................................... 3

CHAPTER 2. FHWA’S BRIDGE PRESERVATION PROGRAM ........................................ 5

CHAPTER 3. DEVELOPMENT APPROACH......................................................................... 9

CHAPTER 4. ASSESSMENT OF RESEARCH GAPS FOR THE 10 TOPIC AREAS 

FROM THE 2008 ROADMAP.................................................................................................. 11

Topic 1: Sensing Data in Bridge Preservation Decisionmaking ....................................... 11

Background and Originally Proposed Objective and Scope ............................................. 11

State of the Practice Based on Literature Review............................................................. 11

Related Work From the FHWA NDE Laboratory............................................................ 13

Observed Gaps .................................................................................................................. 14

Topic 2: Effects of Bridge Preservation Activities............................................................. 15

Background and Originally Proposed Objective and Scope ............................................. 15

State of the Practice Based on Literature Review............................................................. 15

Related Work From Long-Term Bridge Performance (LTBP) Program.......................... 16

Observed Gaps .................................................................................................................. 18

Topic 3: Best Practices for Bridge Deck Preservation ...................................................... 18

Background and Originally Proposed Objective and Scope ............................................. 19

State of Practice Based on Literature Review................................................................... 19

Observed Gaps .................................................................................................................. 20

Topic 4: Preservation of Concrete Highway Bridge Substructure .................................. 21

Background and Originally Proposed Scope and Objective ............................................. 21

State of the Practice Based on Literature Review............................................................. 21

Observed Gaps .................................................................................................................. 23

Topic 5: Corrosion Prevention and Mitigation Technologies for Concrete 

Components........................................................................................................................... 23

Background and Originally Proposed Scope and Objective ............................................. 24

State of the Practice Based on Literature Review............................................................. 24

Related Work From the FHWA Coatings and Corrosion Laboratory .............................. 25

Observed Gaps .................................................................................................................. 25

Topic 6: Deterioration Modeling Accounts for Preservation Actions and Preservation 

Effects..................................................................................................................................... 26

Background and Originally Proposed Scope and Objective ............................................. 26

State of Practice Based on Literature Review................................................................... 26

Observed Gaps .................................................................................................................. 27

Topic 7: Watertight Joints................................................................................................... 28

Background and Originally Proposed Scope and Objective ............................................. 28

State of the Practice Based on Literature Review............................................................. 28

Observed Gaps .................................................................................................................. 29

Topic 8: Development of Bridge Maintenance Database .................................................. 30

Background and Originally Proposed Scope and Objective ............................................. 30

State of the Practice Based on Literature Review............................................................. 30
iv

Observed Gaps .................................................................................................................. 31

Topic 9: Applying Element Data in Bridge Preservation and Management ................... 32

Background and Originally Proposed Scope and Objective ............................................. 32

State of the Practice Based on Literature Review............................................................. 32

Observed Gaps .................................................................................................................. 33

Topic 10: Pile Preservation and Steel Corrosion Prevention............................................ 34

Background and Originally Proposed Scope and Objectives........................................... 34

State of Practice Based on Literature Review................................................................... 34

Observed Gaps .................................................................................................................. 35

CHAPTER 5. RESEARCH TOPICS........................................................................................ 37

Corrosion Evaluation, Prevention, and Mitigation for Bridge Preservation .................. 37

Data for Bridge Preservation ............................................................................................... 37

Element Data in Bridge Preservation and Management................................................... 38

NDE/SM Data in Bridge Preservation and Management ................................................. 38

Other Data for Bridge Preservation and Management ...................................................... 38

Bridge Preservation and Management of Lifecycle Planning .......................................... 39

Cost modeling ................................................................................................................... 39

Deterioration modeling ..................................................................................................... 39

Decisionmaking ................................................................................................................ 39

Ecofriendly and Sustainable Materials and Technologies for Bridge Preservation 

and Repair ............................................................................................................................. 40

Bridge Deck Preservation and Management...................................................................... 40

Preservation of Superstructure and Substructure............................................................. 41

Preservation of Bridge Piles................................................................................................. 41

Preservation of Watertight Joints ....................................................................................... 42

CHAPTER 6. REVIEW AND RANKING ............................................................................... 45

CHAPTER 7. STATEMENT FOR SELECTED TOPICS ..................................................... 47

CHAPTER 8. CONCLUSIONS................................................................................................. 53

APPENDIX. STATEMENTS FOR OTHER TOPICS............................................................ 55

ACKNOWLEDGMENTS .......................................................................................................... 59

REFERENCES............................................................................................................................ 61
v 

LIST OF TABLES

Table 1. High-priority bridge preservation research topics. ..........................................................42

Table 2. Statements for the top 10 research topics. .......................................................................47

Table 3. Statements for other topics. .............................................................................................55
vi 

LIST OF ABBREVIATIONS AND ACRONYMS

3D three dimensional

AASHTO American Association of State Highway and Transportation Officials

ADE Agency Developed Elements 

AE acoustic emission

AI artificial intelligence

BEAST® Bridge Evaluation and Accelerated Structural Testing

BME Bridge Management Elements

BPETG Bridge Preservation Expert Task Group 

BIM bridge information modeling

CFRP carbon-fiber-reinforced polymer

CGR continuously galvanized rebar 

DOT department of transportation

EDC-6 Every Day Counts-6 

FHWA Federal Highway Administration

FRP fiber-reinforced polymer 

GFRP glass-fiber-reinforced polymer 

HPMS Highway Performance Monitoring System

LCCA lifecycle cost analysis

LTBP Long-Term Bridge Performance

MFL magnetic flux leakage

MMF magnetomotive force 

MSEW mechanically stabilized earth wall

NBE National Bridge Elements

NBI National Bridge Inventory 

NBMD National Bridge Maintenance Database

NCHRP National Cooperative Highway Research Program 

NDE nondestructive evaluation 

NHI National Highway Institute 

ROI return on investment

SHM structural health monitoring

SM structural monitoring

SME subject matter expert

TC3 Transportation Curriculum Coordination Council 

TRB Transportation Research Board

TSP2 Transportation System Preservation Technical Services Program

UAV unmanned aerial vehicle 

UHPC ultra-high performance concrete

WG working group 

WIM weigh-in-motion 

XML Extensible Markup Language
1 

EXECUTIVE SUMMARY

The Federal Highway Administration (FHWA) worked with the American Association of State 

Highway and Transportation Officials (AASHTO) in 2008 to develop the Transportation System 

Preservation Research, Development, and Implementation Roadmap to reach consensus about 

the most pressing research needs to move the preservation of roads and bridges into more 

common practice.(1) Since then, most State departments of transportation (DOTs) have 

established bridge preservation programs and have made significant progress in bridge 

preservation practice and research. State DOTs have investigated, developed, and used bridge 

preservation technologies, materials, planning strategies, and tools to extend the service life of 

existing bridges in a cost-effective way. Equally important is considering bridge preservation and 

service life during the planning and design stages of new construction. Adopting higher 

performance materials and lower maintenance structure types and details to extend 

maintenance-free service life is also an important research area for bridge preservation. In recent 

years, dramatic developments in data collection, analysis, and modeling technologies have made 

data-driven performance evaluation and risk-based decisionmaking more practical and efficient. 

Given the promotion of bridge preservation as a cost-effective approach to maintaining bridges 

in states of good repair, there is a need to reevaluate the 2008 roadmap to determine whether the 

gaps are still valid and identify new gaps. 

Publications and research led by FHWA, State DOTs, and AASHTO from 2010 to 2022 was 

reviewed to gain useful information for the gap assessment. Research topics were identified to 

cover the gaps and investigated bridge-preservation-related research topics representing 

emerging technologies and new initiatives. They are ranked to show current FHWA priorities 

and national interests. Data-driven planning and decisionmaking are major research areas 

proposed in this roadmap. Additional gaps and research topics were also identified to support 

FHWA initiatives in climate change, resilience, infrastructure digitization, AI and big data 

related to bridge preservation. 

This roadmap is intended for use primarily by FHWA. Local, State, and other Federal agencies 

or other interested parties may also use the roadmap in selecting and funding research in bridge 

preservation programs. The roadmap should be updated regularly. 

3 

CHAPTER 1. BACKGROUND

In 2008, the Federal Highway Administration (FHWA), American Association of State Highway 

and Transportation Officials (AASHTO), and highway preservation industries worked together 

to identify the most needed research, document critical knowledge gaps in pavement and bridge 

preservation, and determine the research necessary to fill those gaps.(1) This effort resulted in an 

infrastructure preservation research publication called the Transportation System Preservation 

Research, Development, and Implementation Roadmap. The purpose of the 2008 roadmap was to 

reach consensus about the most pressing research needs to move the preservation of roads and 

bridges into more common practice and to provide decision tools to assist agencies with proper 

project selection, use of materials and specifications, quality construction, and appropriate 

performance monitoring. The 2008 roadmap was developed when many States were in the 

earliest stages of implementing preservation practices. Recently, FHWA updated and published 

the pavement portion of the roadmap.(2)

In 2008, many agencies limited bridge preservation to joint repairs, preservation coatings, and 

protective deck treatments. The bridge portion of the 2008 research roadmap identified 

25 research topics and developed research needs statements amounting to a total estimated cost 

of $12.7 million.(1) The 25 topics were distributed among six topic areas as follows: 

• Asset management: 7.

• Decks and joints: 4. 

• Superstructures: 5.

• Substructures: 5.

• Selection of preservation actions: 2.

• Performance of preservation actions: 2. 

Since the 2008 roadmap’s publication, coupled with the Moving Ahead for Progress in the 

21st Century Act(3) and the Fixing America’s Surface Transportation Act(4), significant progress 

has been made in bridge preservation and management research and practice and the impact on 

the performance of individual bridges and bridge networks. States recognize that maintaining an 

aging bridge inventory in a state of good repair with limited budgets is challenging. A worst first 

bridge management approach that focuses only on replacing poor bridges while ignoring the 

preservation and maintenance needs of good- or fair-condition bridges is inefficient and cost 

prohibitive in the long term.(5,6) The National Bridge Inventory (NBI) had 42,966 bridges (with a 

total deck area of 217 ft2

) in poor condition.(7) The replacement cost would be $49 billion based 

on the replacement unit cost reported to FHWA, which was $228 per ft2 on average in 2022 

(https://www.fhwa.dot.gov/bridge/nbi/sd2020.cfm).(8)

Additionally, if no preservation actions are undertaken, the total replacement cost would increase 

exponentially due to the average age of existing highway bridges—which was 45.9 yr in 2022. In 

contrast, delaying the need for costly rehabilitation and replacement while bridges are still in 

good or fair condition through bridge preservation and, at the same time, keeping a good balance 

between bridge preservation, rehabilitation, and replacement are proven effective and practical 

ways to maintain and possibly improve the bridges’ overall service levels.(5,6) Using preservation 
4 

to maintain system conditions and extend bridge service life is a valuable tool for achieving the 

asset management goals FHWA is promoting.

Currently, most State departments of transportation (DOTs) have established bridge preservation 

programs to promote effective and sustainable bridge preservation practices. The success of 

those programs relies not only on funding and organizational support but also on innovative 

research that includes the following:

• Develop and validate cost-effective and ecofriendly bridge preservation and maintenance 

techniques.

• Validate the performance of new materials (e.g., corrosion-resistant, high-strength, 

high-durability, and ecofriendly materials) that extend bridge service life.

• Validate and apply early damage and deterioration detection techniques and use the data 

in bridge preservation planning. 

• Collect and use high-quality data—including nondestructive evaluation and structural 

monitoring (NDE/SM) data—to support meaningful data-driven decisionmaking (e.g., 

lifecycle planning considering cost, performance, and risk). 

• Consider resilience and sustainability in bridge preservation planning. 

• Develop data modeling strategies to support innovations in decisionmaking spurred by 

digital deliverables and digital twin technologies, which include bridge information 

modeling (BIM) for bridge implementations.

This roadmap assesses the bridge portion of the 2008 roadmap in terms of what has been 

accomplished and initiated since then, whether the gaps are still valid, and what new gaps 

exist.(1) This roadmap aims to identify current research needs for bridge preservation and rank 

them according to FHWA’s priority and national interest. The author’s review of publications 

and research led by FHWA, State DOTs, and AASHTO from 2010 to 2022 provides useful 

information for this gap assessment. The report proposes research topics to cover the gaps and 

identifies research needs that represent emerging technologies. The identified research topics are 

ranked to show current FHWA priority and national interests. This roadmap was developed 

primarily for FHWA use because the topics discussed are broad and address national needs, but 

it can also guide local, State, other Federal agencies, or other interested parties in selecting and 

funding research in bridge preservation and management programs. The roadmap is expected to 

be updated regularly.
5 

CHAPTER 2. FHWA’S BRIDGE PRESERVATION PROGRAM

Research conducted in response to this roadmap is intended to feed into FHWA’s broader bridge 

preservation program. The following are key activities in the broader program.

FHWA’s bridge preservation program published Bridge Preservation Guide: Maintaining a 

State of Good Repair Using Cost Effective Investment Strategies and Bridge Preservation Guide: 

Maintaining a Resilient Infrastructure to Preserve Mobility in 2011 and 2018, respectively.(5,6)

The guides define bridge preservation terms and identify commonly practiced bridge 

preservation activities. The guides also provide information for State DOTs and other bridge 

owners regarding establishing or improving existing bridge preservation programs as part of an 

asset management program.

In 2020, FHWA published the FHWA Bridge Preservation Expert Task Group [BPETG]

Strategic Plan FY2020–FY2024.

(9) The plan identified four strategic objectives:

1. Share cost-effective bridge preservation strategies that include the following actions:

a. Develop documents on practices adopted or conducted by States or bridge owners. 

b. Develop apps for mobile devices.

c. Develop case studies.

d. Determine the duration of bridge preservation treatments from a bridge condition 

rating perspective.

e. Study next-generation data framework for developing data-driven preservation 

performance estimates.

2. Promote bridge preservation as a component of asset and performance management that 

includes the following actions:

a. Integrate bridge preservation into asset management.

b. Support the development of bridge deck preservation portals. 

c. Communicate how bridge preservation extends the lives of bridges at other venues. 

3. Develop educational materials on bridge preservation that include the following actions:

a. Design Web-based training. 

b. Communicate the importance of bridge preservation as a component of an asset 

management strategy. 

c. Explore the development and deployment of curricular modules on bridge 

preservation—including appropriate references to asset management and lifecycle 

costs—for undergraduate and graduate courses. 

d. Provide technical assistance for local agencies.

4. Foster a collaborative environment that encourages the innovation and adoption of new 

technologies for bridge preservation that include the following actions: 
6 

a. Explore opportunities to improve States’ qualified product list process for owners, 

suppliers, and contractors that identifies new technologies, gaps, and key performance 

indicators.

b. Assist other research sponsors in promoting bridge preservation research.

Since the publication of the strategic plan, BPETG has completed the following case studies: 

• Case Study: Utilization of Cathodic Protection to Extend the Service Life of Reinforced 

Concrete Bridges – An Overview of the Installation and Maintenance of the Cathodic 

Protection Systems Protecting the Howard Frankland and Crescent Beach Bridges (in 

response to a U.S. Government Accountability Office report dated September 28, 

2021).

(10)

• Case Study: Eliminating Bridge Joints with Link Slabs – An Overview of State 

Practices.(11)

• Case Study: Response to Bridge Impacts – An Overview of State Practices.(12)

The FHWA BPETG developed many pocket guides for bridge preservation activities, which can 

be found at https://tsp2bridge.pavementpreservation.org/technical/fhwa/pocket-guides/.

(13)

Recently, FHWA published a report entitled Prioritizing Preservation for Locally Owned 

Bridges.

(14) The report highlights local agency project selection processes for bridge preservation 

activities, funding sources, typical bridge preservation actions, bridge asset management 

practices, and successes and challenges for funding locally owned bridge preservation programs.

In 2022, FHWA published the Reference Guide for Service Life Design of Bridges.

(15) This 

document is intended to act as a nonbinding “roadmap” of service life design concepts and 

methods for bridge owners and designers. 

For bridge preservation training, several Web-based training courses were developed and are 

available through the AASHTO Transportation Curriculum Coordination Council (TC3) website 

(https://transportation.org/technical-training-solutions/).(16) Examples of courses include the 

following:

• TC3MN036: Bridge Preservation Guide. 

• TC3MN037: Bridge Cleaning. 

• TC3MN038: Thin-Polymer Bridge Deck Overlay Systems.

• TC3MN039: Removal and Replacement of Bridge Coatings. 

• TC3MN042: Concrete Bridge Deck Patching. 

• TC3MN043: Spot, Zone, and Overcoating Existing Bridge Coatings. 

• TC3MN044: Repair of Bridge Concrete Substructure Elements.

• TC3MN049: Maintenance and Repair of Bridge Bearings.

Many National Highway Institute (NHI) training courses were also developed, including the 

following examples:
7 

• FHWA-NHI-130106A: Bridge Preservation Fundamentals.

(17)

• FHWA-NHI-130106B: Establishing a Bridge Preservation Program.

(18)

• FHWA-NHI-130107A: Fundamentals of Bridge Maintenance.

(19)

• FHWA-NHI-130107C: Maintenance of Movable Bridges.(20)

• FHWA-NHI-130107D: Maintenance of Masonry Bridge Elements.

(21)

• FHWA-NHI-130108: Bridge Maintenance.

(22)

FHWA’s bridge preservation program also published the following documents: 

• Report on Techniques for Bridge Strengthening: Main Report.

(23)

• Manual for Design, Construction, and Maintenance of Orthotropic Steel Deck 

Bridges.

(24) This manual covers bridge engineering topics related to orthotropic steel 

decks, including analysis, design, detailing, fabrication, testing, inspection, evaluation, 

and repair. 

• Methodology for Analysis of Soluble Salts from Steel Substrates.

(25) This report presents 

the results of a laboratory study of the methodology for extraction and analysis of soluble 

salts from steel substrates.

• Proceedings of the 2011 National Bridge Management, Inspection and Preservation 

Conference: Beyond the Short Term.

(26)

 The conference included tracks on bridge 

management, inspection, and preservation, emphasizing how all three interrelated 

disciplines can collaborate to improve the long-term performance of the Nation’s 

highway bridges. 

More information about FHWA’s bridge preservation and management program can be found at 

the FHWA “Bridge Preservation” web page (https://www.fhwa.dot.gov/bridge/preservation/) and 

“Bridge Management” web page (https://www.fhwa.dot.gov/bridge/management/).(27,28)

9 

CHAPTER 3. DEVELOPMENT APPROACH

The author identified research topics based on the assessment of existing and emerging research 

and carried out five steps to fulfill the task:

Step 1. The author worked with the FHWA Research Library to conduct a literature review of 

the previously mentioned 25 bridge-related topics in the 2008 roadmap, classifying the topics 

into 18 groups by considering their similarities and connections.(1) Results from major databases, 

AASHTO, the Transportation Research Board (TRB), FHWA publications, and FHWA- and 

State-DOT-funded projects published after 2010 were documented in a spreadsheet.

Step 2. The author considered 11 of the 18 groups more suited to FHWA research due to their 

fundamental research natures and current national needs. Due to ongoing research, the 

weathering steel-related research was not included in further. More topics can be identified later 

as necessary.

Step 3. The author further analyzed the literature research results of the 10 high-priority topics 

and related FHWA research to identify the potential knowledge gaps.

Step 4. The author proposed research topics to address the knowledge gaps identified in step 3 

and investigated topics for emerging technologies. 

Step 5. The research topics identified in step 4 were prioritized by bridge experts of FHWA and 

stakeholders and developed as project statements for selected topics.

Chapter 4 summarizes the literature review findings and gap analysis results for the 10 

high-priority topics (steps 1 through 3). Based on the gap analysis, future research topics are 

identified (step 4) and summarized in chapter 5. The author collected FHWA internal feedback 

for the roadmap. A working group (WG) representing FHWA, TRB, AASHTO (State DOTs and 

the Transportation System Preservation Technical Services Program (TSP2)), academia, and 

industry was formed and provided feedback on prioritizing the topics and research statements. 

11 

CHAPTER 4. ASSESSMENT OF RESEARCH GAPS FOR THE 10 TOPIC AREAS 

FROM THE 2008 ROADMAP

The literature review covers 10 topic areas identified from the 2008 roadmap and an analysis of 

related ongoing FHWA work.(1) The results from this effort were used to support research gap 

identification.

TOPIC 1: SENSING DATA IN BRIDGE PRESERVATION DECISIONMAKING

NDE/SM technologies were developed rapidly during the past decade. However, integrating 

NDE/SM data into bridge condition evaluation, preservation, and management decisionmaking 

still needs more research. Artificial intelligence (AI) and big-data-based analysis approaches 

show promise in applying NDE/SM data in bridge preservation decisionmaking. Early damage 

detection approaches are needed to facilitate early preservation interventions. The ability to 

model sensing data in the context of digital deliverables—including BIM for bridges and digital 

twins—is important for the next-generation bridge preservation program. 

Background and Originally Proposed Objective and Scope

Unexpected failures of prestressing strand embedded in concrete or encased in ducts have 

happened. In 2008, NDE technology was inadequate to evaluate the condition of such embedded 

and ducted strands for active corrosion and section loss, breakage, grout quality, etc. NDE 

technologies at that time were inadequate to provide condition knowledge that could support 

proactive actions to mitigate or prevent further deterioration or future unanticipated failure. Even 

though NDE technologies have improved, technologies focused on determining the current 

condition and identifying active corrosion or conditions favorable to corrosion are needed. This 

research aims to improve the current state of inspection technologies or to develop new tools and 

methodologies for assessing the current state of steel prestressing strand, ducts, cables, and 

ropes. Some of the technologies will focus on determining the current condition, and others will 

focus on identifying active corrosion or conditions favorable to corrosion. 

State of the Practice Based on Literature Review

The literature review results showed that extensive research has been conducted in the past 10 yr 

for NDE/SM techniques and their applications in corrosion and damage detection for prestressed 

strand/tendon/rope, ducts, and grouting. 

The studied NDE/SM techniques included acoustic emission (AE), eddy current, 

fiber-optic-based sensing technologies, ground penetration radar (GPR), impact echo (IE), 

impact-elastic wave, infrared and induction thermography, magnetic- and electromagnetic-based 

methods, magnetic flux leakage (MFL), magnetic flux methods, magnetomotive force (MMF) 

ultrasound, robot, sensor network, three-dimensional (3D) microwave camera, ultrasonic shear 

wave imaging device, and x-ray image and other radiography techniques, etc.

The most used methods for corrosion detection were AE and magnetic flux. Ultrasound and 

impact echo were widely used in grouting-condition evaluation. SM systems were typically used 

for stress and axle force monitoring and damage detection. In addition, radiography was used to 
12 

measure reinforcing configuration, cable and strand or grouting-condition evaluation, and stress 

levels.

Among the 315 results, 74 were from industries other than bridges. The NDE/SM techniques 

used by the bridge industry and other industries were generally similar. The literature review 

yielded the following results: 

• Forty papers discussed AE or acoustic-based methods, and 13 focused on corrosion 

detection. 

• Forty-four results were related to the magnetic flux method, including MMF and MFL, 

and 13 focused on corrosion detection. 

• SM was used to provide real-time or near-real-time information for conditions or stresses 

in cables or strands. Much of the research was about fiber-optic piezoceramic sensors and 

sensor networks. Twenty-one results were about fiber-optic sensors, and 15 of them were 

used to monitor stress and axial force in prestress strands or posttensioned cable. Four 

results were about piezoceramic transducers used to evaluate stress level, cable condition, 

and grouting condition. Sensor network was widely used in cable condition evaluation. 

• For dynamic testing, nine results documented systems for cable and strand stress 

evaluation and damage detection. 

• Twelve results were found for radiography that measured stress level, reinforcing 

configuration, cable and strand condition, grouting condition, etc. 

• One result was for an ultrasonic shear wave imaging device.

• Six results were found for eddy current. The technology was used to evaluate stress level, 

reinforcing configuration, wire rope condition, etc. 

• Thirty-seven results were found for ultrasonic or guided ultrasonic waves. Ultrasonic 

waves are widely used in grouting-condition evaluation (9 papers), corrosion detection 

(9 papers), and stress-level evaluation (10 papers). 

• Magnetic-based methods (28 results) were commonly used in stress-level evaluation.

• Two results were found for lethal-concentration oscillation, which is used in stress-loss 

evaluation. 

• Five results were found for impulse hammer, which is commonly used in condition 

evaluation of posttensioned structures (e.g., grouting-condition evaluations). 

• Six results were found for image-based methods, three of which were about applications 

for wire rope condition evaluation.
13 

• Twenty-three results were about impact echo and impact-elastic wave, whose most 

common application was grouting-condition evaluation, and 14 out of the 23 results were 

about impact echo and impact-elastic wave.

• The 11 results found for robot were all applications in posttension cable condition 

evaluation. 

• Six papers used an AI data analysis approach. 

• The impedance method, with five results, was most commonly used in grouting-condition 

evaluation. 

Related Work From the FHWA NDE Laboratory 

FHWA’s NDE Laboratory led several research projects that are closely related to bridge 

preservation and management. The scope of these projects are about general applications of 

NDE/SM in bridge condition evaluation rather than only for strand, cables, ropes, and grouting 

in prestressed concrete components. Following are summaries of representative products and 

projects:

• The Nondestructive Evaluation [NDE] Web Manual provides knowledge that fills the gap 

between highway infrastructure practitioners/asset managers dealing with highway 

infrastructure performance challenges and researchers developing and refining NDE 

technologies to support practitioners/asset managers’ efforts. The manual is published 

through the FHWA InfoTechnologyTM portal.

(29)

• Collection of Data with Unmanned Aerial Systems (UAS) for Bridge Inspection and 

Construction Inspection.

(30) 

• Leveraging Augmented Reality for Highway Construction.

(31) 

Some of the ongoing research projects led by FHWA’s NDE Laboratory aim to integrate 

NDE/SM data into bridge management decisionmaking frameworks. Return-on-investment 

(ROI) analysis was carried out in the following projects to justify the cost-effectiveness of using 

NDE and SM techniques in bridge preservation and management decisionmaking: 

• Incorporating NDE and SM Methods into Bridge Deck Preservation Strategies.(32)

This project includes efforts to identify state-of-practice preservation decisionmaking 

processes, define specific NDE/SM thresholds for specific preservation actions, develop 

matrices to incorporate NDE/SM methodology into bridge preservation strategies, and 

examine the economics of incorporating NDE/SM into bridge preservation strategies.

• Structural Health Monitoring (SHM) Current Practice and Web Manual. A Web 

manual for structural monitoring (SM) technologies will be developed and integrated into 

the FHWA InfoTechnology portal.

(29)

 ROI analysis was conducted to justify the 

cost-effectiveness of using SM data in bridge management decisionmaking. 
14 

• Current Practices and Policies of State Highway Agency Bridge and Tunnel Units 

on the Use of Deployment-ready NDE Technologies in Complementing Visual 

Bridge and Tunnel Safety Inspections.(32)

 The primary goal of this project is to enhance 

NDE information and its use in managing bridge and tunnel assets. Project-level-analysis 

and network-level-analysis tools were developed. The ROI for using NDE data in asset 

management decisionmaking was evaluated. 

Through the aforementioned projects, FHWA expects that standard approaches for certain SM 

technologies can be established and more widely adopted. By establishing the framework for 

integrating NDE/SM data into bridge management decisionmaking, the NDE/SM technologies 

would have more potential to be adopted as standard practices to supplement current bridge 

visual inspection.

On the data side, more work can be done for NDE/SM data governance, storage, and data 

analysis and visualization and to investigate AI-based data analysis and integration for 

deterioration modeling. NDE/SM-based model updating in the context of digital as-built and 

digital twin is also worth more research. In addition, NDE/SM techniques that can detect early 

damage and deterioration are needed to facilitate cost-effective early preservation interventions.

Observed Gaps

The literature review identified the following research gaps:

• Developing/Testing NDE/SM techniques that could detect early damage/deterioration to 

facilitate cost-effective early preservation interventions.

• Integrating NDE/SM data into bridge components and elements in deterioration modeling 

and remaining service life estimation to support bridge preservation planning. AI- and 

big-data-based data analysis is expected to generate useful information to support 

data-driven bridge preservation and management decisionmaking. 

• Integrating NDE/SM data into digital as-built (BIM for bridges) and digital twin models, 

which could be the next-generation data environment for bridge preservation 

decisionmaking. 

• Applying existing and recently completed work conducted by FHWA’s NDE Laboratory 

to bridge preservation decisionmaking—such as integrating UAS, unmanned 

ground-based systems such as those with data collected by NDE robot, and unmanned 

water-based systems such as those with underwater sensing data—in bridge condition 

and postdisaster condition evaluation. Using virtual-reality- or augmented-reality-based 

bridge inspection data in model updating and data visualization would enable bridge 

preservation engineers to understand bridge condition more intuitively and accurately and 

thus improve preservation decisionmaking. 
15 

TOPIC 2: EFFECTS OF BRIDGE PRESERVATION ACTIVITIES

Understanding the effects of bridge preservation activities is important in decisionmaking. 

Postaction deterioration modeling and remaining service life prediction have not been fully 

studied. For many new materials and new technologies, long-term performance data can be 

obtained only from accelerated laboratory testing or numerical simulation. The ability to validate 

accelerated testing and numerical simulation results is important for practical applications. In 

addition to performance modeling, the cost and ecoimpact of bridge preservation activities are 

important in decisionmaking.

Background and Originally Proposed Objective and Scope

Bridge preservation is a systematic and proactive effort to sustainably extend the service life of a 

bridge or bridge elements. Limited attempts have been made to collect high-quality data, 

properly analyze the data, and draw conclusions about the costs, effectiveness, and longevity of 

preservation actions. Examining such issues as how long the service life of a bridge or bridge 

element is extended or the effects that various commonly used preservation actions have on the 

lifecycle costs of bridges is difficult. Most of the conclusions bridge practitioners reach are based 

on intuition or simple common sense backed by experience. 

Collection of the data necessary to support the effectiveness and economic analysis of bridge 

preservation activities should be addressed in a logical sequence, starting with short-term studies 

of existing data and going on to future data collections targeting specific elements of the 

performance of bridge preservation actions. 

Identifying the kinds of data needed, such as which performance characteristic needs 

improvement by means of which preservation techniques, is important. Experimental studies 

may be needed to collect the data and evaluate the benefits of specific and commonly used 

bridge preservation actions. 

State of the Practice Based on Literature Review

The literature review results show that most previous research focused on bridge preservation 

and maintenance optimization and planning at project and network levels. That focus involved 

research into deterioration modeling based mostly on NBI and National Bridge Elements (NBE) 

inventory data(33,34)

, cost and depreciation modeling, and decisionmaking procedures. Some 

projects also studied the performance and economic impacts of bridge preservation activities. 

However, researchers rarely study the postpreservation deterioration models. Collecting and 

analyzing data to support the evaluation of service life extension of each intervention were not 

adequately studied. 

The 138 literature review results break down as follows: 

• Sixteen results discussed the effects of bridge preservation and maintenance actions, 

among which seven were about economic impacts, and nine were about performance 

impact.

• Fifteen results discussed individual bridge preservation and maintenance decisionmaking. 
16 

• Nineteen results discussed bridge network preservation and maintenance decisionmaking. 

• Twenty-seven results were about maintenance prioritization and decision models. 

• Sixteen results were about lifecycle planning.

• Five results were about deterioration modeling and service life prediction.

• Three results discussed cost modeling.

• Twelve results discussed performance measurements.

• Seven results were FHWA, State DOT, or AASHTO guides to bridge preservation 

actions.

• Eight results discussed bridge deck preservation. 

• Four papers discussed preservations of historic bridges.

• One result was about data workflow for highway assets. The paper discusses the data 

sharing and information exchange for highway asset management. 

• Five papers focused on other topics. 

Related Work From Long-Term Bridge Performance (LTBP) Program

The LTBP Program is a long-term research effort authorized by the U.S. Congress under the 

Safe, Accountable, Flexible, Efficient Transportation Equity Act: A Legacy for Users(35)

 to 

collect high-quality bridge data from a representative sample of highway bridges nationwide that 

will help the bridge community to better understand bridge performance. 

LTBP InfoBridgeTM (https://infobridge.fhwa.dot.gov) is a comprehensive bridge performance 

portal that enables researchers to develop tools and products that will enhance understanding of 

the performance of highway bridge assets and will lead to more efficient design, construction, 

rehabilitation, maintenance, preservation, and management of those assets.(7) The deterioration 

and performance prediction models and data collected by LTBP and other research programs 

published at this Web portal are expected to be very useful for bridge preservation and 

maintenance planning. 

The LTBP Program published the following series of reports and papers, many of them closely 

related to bridge preservation, asset management, and related data needs:

• The Summary Report: Long-Term Bridge Performance Program Data Collection 

Workshop describes the input received from bridge community subject matter experts 

(SMEs) to assist FHWA in assessing the LTBP Program’s future data collection 

efforts.(36) Previously identified high-priority performance issues were paired into five 

categories (i.e., warm-weather reinforced concrete bridge decks, cold-weather reinforced 

concrete decks, bridge deck joints and superstructure bearings, corrosion protection for 
17 

structural steel, and pretensioned and posttensioned strands), and five WGs were formed 

accordingly. The WGs consisted of SMEs from State highway departments, industry, 

academia, and FHWA, who provided input during group discussions. As reported, 

commonalities between certain data were found among the various WGs, such as climate 

data, joint condition data, and other data. Analysis of the input received from each of the 

five WGs, in addition to lessons learned from past LTBP data collection efforts, resulted 

in developing two overall data collection strategies.

The first strategy identified can be termed a “desk audit” type of data collection. The 

second involves collecting physical and visual data from bridges in the field. 

Data collection requires extensive resources and a strategy to collect data to study the 

long-term performance of bridges. Determining the value of any data and how the data 

can be used when developing the LTBP Program’s future data collection approach is 

imperative. The LTBP Program is currently working on executing two studies to assess 

the overall value of already collected data—namely, data collected through an ongoing 

accelerated testing experiment and data available through earlier LTBP data collection 

efforts—to help guide the path forward. 

The data collected and that will be collected by the LTBP Program constitute an 

important asset for the bridge preservation community’s future research.

• The report Synthesis of National and International Methodologies Used for Bridge 

Health Indices is important for bridge asset management.(37) Deterioration models based 

on elements and health indexes are useful in asset management decisionmaking at both 

the project and network levels. Deterioration models for bridge load ratings would be 

useful tools for evaluating the bridge capacity changes over time. More research into cost 

and cost modeling is needed for bridge asset management. Cost can be financial cost as 

well as environmental cost. With known costs, project- and network-level bridge 

preservation optimization tools can be developed. 

• The Bridge Evaluation and Accelerated Structural Testing (BEAST®) laboratory is the 

world’s first accelerated testing facility for full-scale bridge systems.(38) BEAST subjects 

bridges to extreme environmental and traffic loading to simulate decades of deterioration 

in only months. The facility produces quantitative data on material and component 

performance that can be used to study bridges’ long-term performance and operation. The 

current study covers concrete decking systems, prestressed concrete girders, joints, 

bearings, deck drainage, latex-modified concrete overlay, and ultra-high performance 

concrete (UHPC) overlay systems.

• Other LTBP Program publications can be found at 

https://highways.dot.gov/research/long-term-infrastructure-performance/ltbp/long-termbridge-performance-ltbp-program-publications.

(39)
18 

Observed Gaps

The literature review identified the following research gaps:

• More research is needed to standardize the quality control and performance evaluation 

procedure for bridge preservation actions. 

• More research is needed for using NDE/SM data in bridge deck or other element 

deterioration modeling. 

• More research is needed to develop a standard data collection and governance framework 

for bridge preservation and maintenance activities. A uniform data framework would 

facilitate more efficient data query and sharing and establish a more meaningful data 

analysis supporting bridge preservation and management decisionmaking. 

• BIM data needs and model updating to represent bridge preservation and maintenance 

effects is helpful for preservation decisionmaking.

• Integration of agency-collected data (e.g., Highway Performance Monitoring System 

(HPMS) data, weigh-in-motion (WIM) data, pavement profile and condition data, traffic 

data, friction index data, climate data, cost data, etc.) into bridge preservation planning 

and postactivity performance evaluation. 

• Lifecycle and network-level bridge preservation planning are more advanced than 

project-level bridge preservation decisionmaking. However, research about lifecycle and 

network-level planning is still in the early stages, and more research is needed.

• Research into data sharing and information exchange is needed for the entire lifecycle of 

bridge projects—from planning to design, construction, operation, and management in 

BIM or a digital deliverables context so that bridge preservation and management 

programs can adapt to the next-generation data environment. 

• More research is needed correlating accelerated testing results with field-collected 

performance data for testing validation. Once validated, the tests can be designed to 

simulate performance data that are rarely available or hard to collect in the field.

TOPIC 3: BEST PRACTICES FOR BRIDGE DECK PRESERVATION

Deck preservation has been widely studied during the past decade. The ongoing pooled funded 

project Bridge Deck Preservation Tool (https://www.pooledfund.org/Details/Study/701) and 

Proposed AASHTO Guides for Bridge Preservation Actions

(https://www.trb.org/Publications/Blurbs/181532.aspx) answered many of the previous questions 

about bridge deck preservation activities and selection criteria.

(40,41) However, the existing 

research addressed mainly the single selected treatments of individual bridges . Research into 

individual bridge lifecycle planning and network-level planning for selected bridges is still in the 

early stages and deserves more research. Risk-based performance-driven decisionmaking can 

potentially lead to a more sophisticated and easy-to-implement approach. 
19 

Evaluations of deck sealer and overlay materials, technologies, and best practices are important 

in deck preservation research. Because many ongoing research projects focus on case studies and 

decision tool development, these areas can be revisited later. Emerging research needs for deck 

preservation research may include new materials, the impact of climate change, heavy live load, 

etc.

Background and Originally Proposed Objective and Scope

In current bridge inventory, about 90 percent of bridges have concrete decks. All State DOTs 

recognize the importance of concrete deck preservation. The purpose of deck preservation 

treatments is to protect decks and maximize service life with limited resources. Typical 

treatments include the following:

• Concrete surface and crack sealers.

• Thin overlays. 

• Periodic washing. 

• Electrochemical treatments.

• Cathodic protection. 

• Membranes.

• Coatings. 

Research is needed to establish cost-effective lifecycle preservation programs for maintaining 

and preserving concrete bridge decks. 

State of Practice Based on Literature Review

The 90 literature reviews yielded the following results:

• Eighteen were about manuals, guides, and specifications. 

• Fourteen were about overlays (not UHPC). 

• Eleven were about UHPC overlays, which is also one of the major topics of Every Day 

Counts-6 (EDC-6).

(42)

• Eleven were about decisionmaking. 

• Seven were about waterproof membrane or asphalt overlay. 

• Seven were about service life analysis.

• Six were about the preservation effect or field performance evaluation. 

• Five were about lifecycle cost analysis (LCCA).

• Four were about high-performance or new materials.
20 

• Three were about cathodic protection or chloride extraction. 

• Two were about deck preservation protocols and tools. 

• Two were about construction methods. 

• Other research included sealer, high-friction surface treatment, patching, internal curing, 

cleaning, preservation of posttensioned bridges, link slab, bridge seats and bearings, and 

deck-cracking control and repair. 

Related Work from FHWA EDC-6 (43)

• EDC-6 work with UHPC for bridge preservation and repair lead to the publication of a 

report entitled Design and Construction of UHPC-Based Bridge Preservation and Repair 

Solutions.

(42,43)

 The report contains design and construction recommendations for three 

promising and fastest growing UHPC preservation and repair applications: bridge deck 

overlays, link slabs, and steel beam end repair. The report also includes other key 

concepts of UHPC, such as material mechanical properties and durability. The 

information is valuable for all owner agencies considering the development of UHPC 

materials, construction, and design specifications.

Observed Gaps

The literature review identified the following research gaps:

• Bridge deck preservation decisionmaking has been thoroughly studied at the bridge and 

project levels. However, more study is needed for lifecycle and network-level planning. 

• Fiber-reinforced concrete is gaining attention for bridge deck and deck overlays 

construction to prevent cracking. However, research into the material characteristics and 

field performance data is not yet readily available for use in decisionmaking.

• More research is needed into ecofriendly materials that can be used in bridge deck 

preservation or repair.

• More research is needed into the long-term field performance of corrosion resistant rebar 

(e.g. glass-fiber-reinforced polymer (GFRP), stainless steel, etc.) reinforced concrete 

deck and its preservation needs.

• More research is needed into NDE/SM integration for early deck damage and 

deterioration detection and preservation. 

• More research is needed into collecting NDE or other sensing data from the deck bottom, 

such as by using an unmanned aerial vehicle (UAV) in deck preservation and 

management decisionmaking. 
21 

• More research is needed into the impact of climate change that causes extreme events and 

how changes in the number of snow and freeze–thaw cycles will affect bridge deck 

design, deterioration, and preservation. 

• More research is needed into how live loads (e.g., heavy trucks and truck platooning) 

affect the deterioration of bridge decks and preservation planning. 

• UHPC bridge preservation applications can be further developed and tested in the future. 

Examples are UHPC shotcrete, 3D printing, and UHPC for structural strengthening and 

repair.

TOPIC 4: PRESERVATION OF CONCRETE HIGHWAY BRIDGE SUBSTRUCTURE

Active corrosion is common for bridge substructures. Early prevention actions, such as applying 

surface treatments prior to chlorides reaching critical concentration at rebar depth, are effective. 

However, more research is needed on schedules for applying and reapplying. Once rebar 

corrosion has started, preservation actions that can reduce deterioration rate are needed. In 

addition to specific preservation techniques, strategic decision matrices and tools for preservation 

planning are needed. 

Background and Originally Proposed Scope and Objective

States need to develop guidance that highway agencies can follow in applying technologies that 

prevent or delay corrosion initiation, reduce corrosion rate, extend service life, and enhance the 

long-term durability of concrete bridge substructures. States need to develop strategic decision 

matrices for when and what corrosion mitigation strategies to implement to prolong the service 

lives of in-service highway bridge substructures because gaps still exist.

State of the Practice Based on Literature Review

The literature review results showed that in the past 10 yr, corrosion prevention and mitigation 

techniques were the most studied topics for bridge substructure. Among the topics, cathodic 

protection has been the most studied approach, followed by inhibitor and corrosion-resistant 

rebars.

Marine and coastal environment and the application of chloride deicing agents were found to be 

the two major factors that caused corrosion. Corrosion and remaining service life modeling was 

widely studied. Multihazard and climate change are considered in many of the studies. Research 

was also conducted into corrosion management, lifecycle assessment, and critical chloride 

thresholds. The performance of corroded components was also studied in many previous 

projects. Other studies included corrosion detection for girders, structural steel, steel piles, metal 

culverts (pipes), and mechanically stabilized earth walls (MSEWs).
22 

Following is a summary of approximately 270 literature review results:

• Corrosion mitigation (171 items):

o Cathodic protection was the most studied approach (48 items). 

o Twenty-four were about inhibitors.

o Twenty were about corrosion-resistant rebar.

o Eighteen were about special concrete mixture design.

o Sixteen compared different methods or literature reviews.

o Ten were about rebar coating.

o Eight were about fiber-reinforced-polymer (FRP) external bond/wrap/jacket.

o Eight studies used multiple corrosion mitigation approaches simultaneously. 

o Five results were about electrochemical chloride extraction and electrochemical 

realkalization.

o Ten were about other methods. 

o Four were about concrete surface coating.

• Ninety-two results were about corrosion-impacting factors:

o Sixty-six were about marine and coastal environments. 

o Fourteen were about deicing salt. 

o Twelve were about global warming. 

• Sixty-five of the results were about modeling: 

o Eight were about multihazard modeling. 

o Nine were about how climate change affects corrosion initiation and propagation. 

o Others focused on corrosion deterioration modeling, remaining-life prediction, 

concrete cracking and diffusion, and rebar corrosion modeling.

• Corrosion detection with NDE/SM had 29 results: 

o Half-cell potential was the most studied method and had seven results. 

o Electrochemical-based method had six results. 

o AE had three results.

o Polarization resistance had two results.

o Ground penetration radar had two results.

o Corrosion rate monitoring had four results. 

o Five were about other. 

• Corrosion detection for specific components: Girders (5 results), structural steel 

(3 results), piles (17 results), metal pipeline (1 result), MSEW (2 results).

• Sixteen of the results were about the performance of corroded components. 

• Eight of the results were about corrosion management and LCCA. 

• Four of the results were about critical chloride threshold.
23 

• Six of the results were corrosion-related specifications. 

• Other research included chloride permeability, chloride ponding test improvement, and 

concrete cover crack propagation. Studies focused on concrete crack and rebar corrosion 

modeling, diffusion modeling, cathodic protection modeling, deterioration, and 

remaining-life prediction also exist.

Observed Gaps

The literature review identified the following research gaps:

• More field-collected long-term-performance data is needed for corrosion-resistant rebars 

(e.g., stainless steel rebar, GFRP, carbon-fiber-reinforced polymer (CFRP), and 

microcomposite multistructural formable steel rebar) embedded in concrete. These data 

are critical for bridge design as well as preservation and management decisionmaking.

• More field-collected long-term-performance data for UHPC that can be used to support 

preservation decisionmaking is needed. 

• Many NDE/SM research projects focus on corrosion or corrosion environment detection, 

but very few of them apply the NDE/SM data to bridge preservation and management 

decisionmaking. 

• More research is needed for integrating NDE/SM corrosion detection data into digital 

twin models or BIM models for a real-time model updating that would reflect the 

operational condition of bridges to support bridge preservation decisionmaking. 

• More research is needed to develop an element-based data framework that supports 

defect inspection. 

• Much research is needed on cathodic protection. However, cathodic protection’s adoption 

by State DOTs is limited, and research is lacking about the reasons cathodic protection is 

not more widely accepted by States. 

• More studies are needed that estimate the impact of climate-change-caused accelerated 

corrosion development and how such studies would affect asset management 

decisionmaking. 

• More research is needed for bridge deck, superstructure, and substructure lifecycle 

corrosion management planning. 

TOPIC 5: CORROSION PREVENTION AND MITIGATION TECHNOLOGIES FOR 

CONCRETE COMPONENTS

Corrosion prevention and mitigation are important for preserving the condition and extending the 

service lives of concrete structural components. The cost and performance of available 

preservation actions are essential in decisionmaking, and they are not fully studied or 

documented. 
24 

Background and Originally Proposed Scope and Objective

This research is proposed to conduct an extensive field evaluation of the most common concrete 

structure corrosion protection and mitigation technologies in use since approximately 1980. The 

study should address the following parameters: 

• Initial cost (difference) during construction or postconstruction application. 

• Complexity of installation and construction (e.g., level of effort, training, and 

environmental concerns). 

• Performance since installation—and comparison, if possible, to the performance of 

similar bridges in similar environments without these protective systems.

• Required maintenance (if any) performed to keep the technology functional. 

• Cost of maintenance performed to keep the technology functional. 

State of the Practice Based on Literature Review

Many of the results found in the previous section are also related to the state of the practice. In 

addition to those results, another approximately 110 papers and reports were found from the 

literature review. Most of them focused on preserving concrete bridge decks and superstructures. 

The most studied corrosion prevention and mitigation approach for concrete structures is 

cathodic protection, followed by concrete sealers and sealants or surface-applied inhibitors.

The approximately 110 papers and reports yielded the following results:

• Thirty-three were about cathodic protection. 

• Fifteen were about concrete sealer and sealant or surface-applied inhibitors.

• Nine were about corrosion-resistant rebars.

• Eight were about inhibitors. 

• Six were about concrete or asphalt overlays.

• Five were about epoxy-coated or other coating systems for rebars.

• Four were about the use of lower permeate concrete or special concrete mixtures.

• Four were focused on LCCA. 

• Four compared multiple methods.

• Three were about corrosion prevention of posttension components. 
25 

• Two were about performance-testing methods.

• Other results included studies of multiple impact factors, lifecycle corrosion treatment 

plans and management planning, factors that affect corrosion, etc. 

Related Work From the FHWA Coatings and Corrosion Laboratory 

Determining the corrosion performance of coating and metal materials through laboratory 

approaches is one of the tasks of the FHWA Coatings and Corrosion Laboratory. Publications by 

the laboratory can be found at https://highways.dot.gov/research/laboratories/coatings-corrosionlaboratory/corrosion-coating-publications.

(44) The laboratory’s research projects have covered the 

topics of coatings, corrosion of reinforcing steel, corrosion in prestressed concrete, and others. 

In parallel with laboratory evaluation, field evaluation for material corrosion performance and 

the effect of corrosion prevention methods is still important. More corrosion-resistant materials 

and corrosion mitigation approaches need validation in the laboratory and in the field, with 

exposure to realistic highway operation environments. For example, cathodic protection is one of 

the most studied corrosion prevention and mitigation approaches in the literature and the 

laboratory, but its application in bridge preservation practice is still limited. More laboratory 

research and field performance data would be useful for further validation and future adoption. 

Observed Gaps

The literature review identified the following research gaps:

• The most studied corrosion mitigation method for concrete structural components is 

cathodic protection. However, its adoption by State DOTs is limited. Research into the 

reasons cathodic protection is not more widely accepted by States is lacking.

• More research is needed into the live-load effect on the corrosion performance of bridge 

decks.

• Research into cost information and LCCA or ROI analysis is limited.

• More research is needed into bridge deck lifecycle corrosion management planning. 

• More research is needed into laboratory and field performance concerning 

corrosion-resistant materials, including UHPC.

• More research is needed into how climate change and extreme events affect bridge deck 

corrosion performance. 

• Projects led by the FHWA Coatings and Corrosion Laboratory have provided useful 

knowledge that supports bridge preservation decisionmaking. However, most of the 

studies were based on material-level accelerated laboratory testing. Structure-level and 

field-performance data are needed to validate the laboratory-testing data and thereby 

support more accurate preservation decisionmaking and management planning. 
26 

TOPIC 6: DETERIORATION MODELING ACCOUNTS FOR PRESERVATION 

ACTIONS AND PRESERVATION EFFECTS

Deterioration models are key in bridge preservation decisionmaking. Bridge component 

deterioration modeling has been widely studied during the past decade. However, the 

development of element-based deterioration models, early deterioration modeling that allows for 

early preservation intervention, and postaction modeling are all in their early stages.

Background and Originally Proposed Scope and Objective

States need to study the performance of various bridge preservation actions and develop 

deterioration models that account for the performance of preservation actions in bridge 

management calculations.

States need to develop quantitative models of the time until onset of deterioration and become 

sensitive to adherence to preventive maintenance policies. Models would be quantified for 

common routine maintenance treatments, such as washing and sealing, and agencies could 

extend the models for other types of preventive maintenance. Such models would be developed 

according to the AASHTO Guide to Commonly Recognized (CoRe) Structural Elements and 

would be compatible with their standardized condition state language for visual inspection.(45)

State of Practice Based on Literature Review

The literature review found 426 results, among which the most widely studied topics were 

deterioration modeling (153 items) and bridge asset management (60 items). Transportation 

Pooled Fund-5(432) Bridge Element Deterioration for Midwest States is one of the pilot 

projects.(46) In the project, element deterioration models were developed using new element data 

and taking a Markov chain approach. Relevant data were collected from participant States, and, 

along with inventory data and collected NDE data, the collected maintenance information was 

saved in a SQL database to facilitate future updates and easy data sharing. Most of the asset 

management topics found from the literature review focused on maintenance and inspection 

planning: 

• One hundred fifty-three results were about deterioration modeling. 

• Thirteen were about survival and transition analysis. 

• Sixty-two were about bridge asset management: preservation or maintenance planning.

• Eighteen were about bridge inspection intervals and maintenance planning and 

optimization.

• Seventy were about bridge preservation, maintenance, and repair activities. 

• Eleven were about the impact of preservation and maintenance activities or the impact of 

investment. 

• Fifteen were about performance evaluation or new performance measurements.
27 

• Fifteen were about cost models.

• Fifteen were about bridge service life prediction or remaining service life.

• Six were about the risk and resilience of bridges.

• Thirty-eight were about lifecycle analysis.

• Ten were about BIM or digital twin or data-sharing workflow. 

• Other topics included one repair of bridge approaches, three for detection of abnormal 

behaviors, two for cracking predictive models, two for service life design, two for 

corrosion modeling, one for seismic fragility study, one for robust modeling, one about 

NBE and NBI conversions, one about the effect of climate change, three about health 

index, and two about sustainability. 

Observed Gaps

The literature review identified the following research gaps:

• More research is needed into deterioration modeling that considers: 

o Impact of climate change.

o Impact of heavy truckload. 

o Effect of bridge preservation and maintenance activities. 

o Structural capacity.

• More research is needed into the environmental footprint, performance impact, and 

lifecycle cost impact of bridge preservation and maintenance activities.

• More research is needed into resilience and how resilience affects bridge preservation 

decisionmaking. 

• More research is needed into substructure and foundation preservation and maintenance 

activities.

• More research is needed into data-sharing requirements for supporting bridge operation 

and asset management in BIM or digital twin environments.

• More research is needed to identify and collect data for early stage deterioration 

modeling that supports preservation decisionmaking.

• More research is needed into risk-based bridge preservation planning. 
28 

TOPIC 7: WATERTIGHT JOINTS

Joint leakage is the major factor that caused the deterioration of adjacent decks, beam ends, and 

bearings. Eliminating joints by using integral abutment and link slabs is an effective way to 

avoid such maintenance issues. Joint maintenance, replacement, and repair actions and related 

performance evaluations are needed for existing bridges. 

Background and Originally Proposed Scope and Objective

Maintaining watertight joints is essential preserving the condition of adjacent decks, 

superstructures, and substructures.

State of the Practice Based on Literature Review

The literature review extended the original scope to general joints-related research; 191 papers 

were found, of which 160 or so were about bridge deck joints. The most studied topic was joint 

sealant and filler. The joint maintenance, replacement, and repair of UHPC and fiber-reinforced 

joints and link slabs were all studied at different levels. Some studies also involved deterioration 

modeling for joints. Details of the literature review results are summarized as follows:

• Five papers discussed jointless bridges and eliminating joints on existing bridges. The 

author concluded that elimination of transverse joints is a practical and cost-effective 

approach to avoiding joint leakage and leakage-induced damage and corrosion of 

bearings, superstructures, and substructures.

• Nine papers were about link slab studies. Materials for link slabs, link slab design and 

construction, and analysis approaches were studied. Link slabs were effective in 

eliminating deck joints.

• Fifteen papers were about UHPC joints, and six papers were about fiber-reinforced 

concrete joints. UHPC for bridge preservation and repair is one topic of EDC-6.(42)

• Twelve papers were about longitudinal joints, which included longitudinal joints for 

wider decks, joints between box girders, or joints between other adjacent concrete 

members.

• Twelve papers were about expansion joints. Materials, installation procedure, 

maintenance, replacement of all types of expansion joints, and sealant and filler materials 

were thoroughly documented. 

• Five papers discussed asphalt expansion joints (asphalt plug joints). 

• Three papers discussed strip seal.

• Twenty-three papers discussed joint sealant and filler.

• Three papers discussed sealer and membranes.
29 

• Two papers discussed modular joints. 

• One paper was about ribbed loop joint, and one paper was about half joint. 

• Six papers were about joint design. 

• Two papers were about joint cleaning. 

• Five papers were about LCCA.

• Two papers were about joint management systems and asset management.

• Eight papers were about material testing.

• Eleven papers were about material standards.

• Sixteen papers were about joint maintenance, replacement, and repair.

• Four papers were about joint monitoring. 

• Seven papers were about performance assessment and deterioration modeling.

• One paper was about pier cap and beam end repair caused by joint leakage.

Observed Gaps

The literature review identified the following research gaps:

• Nationwide case studies to identify and document best practices for expansion joints, 

jointless bridges (including joint elimination), and associated LCCA are needed. 

• The link slab concept is relatively new; more studies can achieve a better understanding 

for material selection (fiber-reinforced concrete, UHPC, or regular concrete), behavior, 

and performance. Such studies could lead to the development of guidelines for link slab 

design, construction, monitoring, and preservation. UHPC link slab is one topic regarding 

the current EDC-6 UHPC for bridge preservation.(42)

 The advantages of replacing 

expansion joints with UHPC link slab were documented. The design of UHPC link slab 

was also studied and documented. However, the long-term performance of UHPC link 

slabs and their deterioration, maintenance, and preservation still need investigation. In 

addition, the behavior of link slabs on bridges in seismic zones needs study. 

• More work is needed on bridge deck joint deterioration modeling. 

• A joint selection decision tool needs to be developed. 

• The problem caused by longitudinal joints was observed, but solutions need to be fully 

studied and recommended.
30 

• Maximum span length for integral abutment needs to be established at the national level. 

Considering bridge preservation during design is also important. 

• Replacement of stub abutments on existing bridges with semi-integral abutments can 

reduce joint maintenance needs and be economical from a lifecycle point of view. LCCA 

can be used to justify the cost effectiveness.

• Long-term monitoring of performance of joints is needed.

• Workflow and data sharing for joint management need to be identified as a component of 

BIM for bridge maintenance and management. (No work has been done to develop data 

dictionaries of joint elements).

TOPIC 8: DEVELOPMENT OF BRIDGE MAINTENANCE DATABASE

The National Bridge Maintenance Database (NBMD) was proposed and framed in National 

Cooperative Highway Research Program (NCHRP) 14-15 to enable DOTs to evaluate the costs 

and performance of maintenance actions, execute cost–benefit analysis, and better manage 

bridge maintenance resources.(47) The data and data format suggested in the database are useful 

for understanding the performance and cost of maintenance activities. It would be helpful if State 

DOTs’ adoption status and update suggestions could be investigated and the system updated to 

reflect current needs.

Background and Originally Proposed Scope and Objective

NCHRP 14-15 has developed a standardized data structure for reporting and sharing bridge work 

accomplishment data.(47) The researchers proposed the project to gather bridge work 

accomplishment data in NCHRP 14-15 format from any agency able to provide such data. The 

project then quantified production functions, cost functions, and outcome functions as envisioned 

in the 14-15 report. The production functions and cost models account for both direct and 

indirect resource inputs.

State of the Practice Based on Literature Review

NCHRP 14-15 provided a framework for a database system—NBMD—for uniform reporting of 

bridge maintenance actions.(47) The database is in a uniform and readable format for bridge 

maintenance, condition, and inventory data. The database conforms with the NBI format. NBMD 

collects outputs from existing DOT data systems and casts the outputs into a standard format. 

The database was designed to have 13 tables presenting bridge maintenance activities along with 

bridge inventory and condition data. The data formats include tab-delimited text files and 

Extensible Markup Language (XML) documents, each conforming to a standard XML schema.

Instead of focusing only on topics related to NCHRP 14-15, the literature review was extended to 

include general topics of cost modeling.(47)

 Among the 300 or so results, 171 were bridge related; 

others focused more on pavement, roadway, or other infrastructure structures. The most studied 

topics focused on cost estimation, probabilistic modeling, prediction modeling, and risk and 

uncertainty estimation. The following is a summary of the results: 
31 

• Four were about State implementation of a construction cost index. 

• Fifty-six were about general cost estimation.

• Forty were about maintenance cost. 

• Thirty-two were about user cost, and four about user and agency costs. 

• Twenty-four were about asset management.

• Fifteen were about early cost estimation—either preconstruction cost or cost estimation 

made during planning or preliminary design. 

• Fourteen focused on construction cost only. 

• Fourteen were about cost overrun. 

• Thirteen were about work zone cost (most were user cost).

• Thirteen were about network-level analysis.

• Eight discussed cost data integration with BIM models. 

• Eight were about the cost benefit of activity-based-costing. 

• Five were about cost due to lane closure.

• Three were about construction material quantities and time estimation.

• Two were about network cost. 

• Two were about congestion cost. 

• Other topics included one about accident cost, one about night construction, one about 

pay items from the design development process, one about cost and demand forecast, one 

about cost comparison between using in-house staff and using a consultant, one about 

incentive study, one about sustainable bridge invention strategies, one about project delay 

cost, and one about asset valuation.

Observed Gaps

The literature review identified the following research gaps:

• More research is needed into adopting an NCHRP 14-15 national maintenance database 

and the need for updating.(47)

• More research is needed into data frameworks and governance for cost information 

collection and application.
32 

• More research is needed into lifecycle cost savings due to emerging technologies, such as 

the adoption of BIM design, digital deliveries, and remote sensing and virtual reality for 

construction management and truck platooning. 

• More research is needed into cost impacts due to climate-change-caused bridge 

preservation needs.

• More research is needed into lifecycle cost due to live-load changes: increasing average 

daily truck traffic, truck weight, and truck platooning. 

• More research is needed into lifecycle costs of bridge preservation activities.

• More research is needed into element-based bridge preservation costs. Data on elementbased preservation activities and costs need to be collected, and best practices established 

through case studies would be helpful. 

• More research is needed into the use of environmental cost or carbon footprint as an 

optimization factor in bridge management.

TOPIC 9: APPLYING ELEMENT DATA IN BRIDGE PRESERVATION AND 

MANAGEMENT

New AASHTO elements were adopted into bridge inspection practice in 2014, which addressed 

most of the research needs identified in the 2008 roadmap.(48,1) In the current NBE data system, 

element data do not provide damage location information.(34)

 The computed health index 

considers only damage quantity, not location. Damage location information is important for 

performance evaluation and preservation decisionmaking. Recent developments in project 

deliverables, bridge inspection and operation, and other technologies have generated new 

research requirements and opportunities for bridge elements.

Background and Originally Proposed Scope and Objective

This research will develop a recommendation to modify and supplement the current list of 

elements. The proposed modified and new elements will be presented to AASHTO’s bridge 

management community for adoption and integration into current and future bridge management 

systems.

State of the Practice Based on Literature Review

The new AASHTO elements adopted in 2014 addressed most of the previously identified 

research needs for NBE data.(48) Current bridge elements have three categories: NBE, Bridge 

Management Elements (BME), and Agency Developed Elements (ADE). Regarding ADEs, 

agencies can define their own elements as subsets of NBE/BME (e.g., beam ends) or 

independent agency-defined elements (e.g., movable bridge components). All elements have four 

fixed-condition statuses. During the 8 yr of implementation of AASHTO elements inspection, 

more and more State DOTs have been creating different ADEs. Some of the created ADEs might 

also be useful for other States or bridge owners. Awareness of ADE development status will help 

evaluate the potential to adopt ADEs as NBE or BME. 
33 

Meanwhile, detailed information about bridge elements is more readily available due to the 

implementation of digital deliverables. The development of a bridge data dictionary for digital 

as-built, digital twin, or BIM models—along with identifying information exchange 

requirements for bridge operation, inspection, and management—provides the opportunity to 

include more information for current bridge elements or to identify the need for new elements for 

special bridges. In addition, planning for next-generation bridge element systems within digital 

deliverables and BIM frameworks can never start too early.

The literature review found 50 results. Following is a summary of the findings: 

• Fourteen results were about applying element data in bridge asset management.

• Sixteen results were about element inspection manuals. 

• Two results were about the UNIFORMAT II (ASTM E2103) classification of bridge 

elements.(49)

• Two results were about new elements.

• Five results were about BIM, a data dictionary, and 3D modeling. 

• Two results were about more information for elements.

• Two results were about element data and NBI data conversion.(33)

• One result was about definitions of bridge preservation, maintenance, and replacement. 

• One result was about defining significant predictors for bridge health indexes and 

defining bridges in poor condition with element data. 

• Five results were about other content.

Observed Gaps

The literature review identified the following research gaps:

• More research is needed into element inspection that supports effective and systematic 

defect and maintenance reporting. Development of an effective and systematic defect 

inspection and maintenance activity reporting framework is needed. 

• More research is needed to identify new bridge elements for special bridges (e.g., 

movable bridges) or to incorporate additional information (e.g., location or position 

information like beam ends or more precise position information associated with damage 

and deterioration) into existing elements. Such information is important in bridge 

management decisionmaking. 

• Research is needed to evaluate ADE and determine its potential for adoption as NBE or 

BME.
34 

• More research is needed to develop next-generation bridge elements within digital 

as-built, digital twin, or BIM frameworks. Developing a new bridge element system in 

the digitalization context would never be too early.

• More research is needed to develop a risk index using inventory data and other available 

information (e.g., NDE/SM data, failure probability data, and failure consequence data) 

to support bridge preservation planning. 

TOPIC 10: PILE PRESERVATION AND STEEL CORROSION PREVENTION

Corrosion is the most common damage and deterioration mode for steel bridge piles. The topic 

covers research related to performance evaluation, corrosion prevention and mitigation, and 

damage repair of steel piles.

Background and Originally Proposed Scope and Objectives

This research aims to develop one or more methods to determine the condition of and remaining 

service life of in-service exposed and unexposed steel piles in environments of varying 

aggressiveness and to identify methods to preserve such piles.

State of Practice Based on Literature Review

Most of the previous research focused on steel pile corrosion mitigation and repair. Among the 

57 results, cathodic protection was the most widely studied algorithm, followed by FRP repair. 

Some projects also studied NDE/SM techniques for corrosion and damage detection, factors that 

affect corrosion development, and the performance of corroded piles. Other topics also studied 

included corrosion rate and simulation, pile fatigue, coasting, coating effects on force and 

deformation characteristic of steel piles, drilled shafts, sheet piles, pipe piles, foundation reuse, 

durability, soil-pile interaction modeling, fragility analysis, response to bridge foundation failure, 

LCCA, pile-type selection criteria, and service life of a steel structure.

The 145 literature reviews yielded the following results: 

• Fifty-four were about corrosion mitigation and repair:

o Cathodic protection was the most studied technology (18 results). 

o FRP repair was also very well studied (17 results).

o Other approaches included coating (seven results), metal cold-air spray (one result), 

thermal spray (one result), petrolatum-based wrap (three results), UHPC (three 

results), concrete jacket (three results), and bolted or welded steel shapes or plates 

(one result).

• Twenty-eight were about factors affecting corrosion development:

o Four were about the environment. 

o Three were about climate change.
35 

o One was about expansion joint degradation. 

o One was about salt effect.

o Four were about soil properties. 

o Four were about dissolved inorganic nitrogen. 

o Ten were about fouling and antifouling coating or microbiologic-influenced corrosion 

and deterioration. 

o One was about contaminated water. 

• Thirteen were about the performance of corroded piles.

• Eight were about NDE for corrosion detection: 

o Two were about ultrasonic-guided waves.

o Two were about eddy currents. 

o One was about sonic echo impulse response. 

o Two were about pile depth estimation. 

o One was about surface topography. 

• Four were about repair methods and decisionmaking matrices. 

• Four were about the analysis, design, and construction of steel piles. 

• Two were about corrosion rate and corrosion simulation. 

• Two were about steel pile fatigue.

• The remaining 30 reviews included coating effects on force and deformation 

characteristics of steel piles, drilled shafts, sheet piles, pipe piles, foundation reuse,

durability, soil pile interaction modeling, fragility analysis, response to bridge foundation 

failure, LCCA, pile type selection criteria, and service life of steel structures.

Observed Gaps

The literature review identified the following research gaps:

• More study of element-based steel pile deterioration modeling is needed.

• More research is needed into integrating NDE/SM data into early corrosion and 

deterioration modeling and prevention decisionmaking. 

• More research is needed into underwater NDE technologies (e.g., underwater inspection 

robots) that can collect useful data to support pile management decisionmaking. 

• More research is needed into SM for corroded piles to collect performance data to 

support decisionmaking and policy making.

• More study is needed on cost data collection and modeling that supports steel pile 

preservation and maintenance planning. 
36 

• More study is needed on how the performance of steel piles is affected by climate 

change, live-load change, and extreme events and how performance, in turn, affects 

preservation and management decisionmaking. 

• More study is needed on why cathodic protection is not more widely accepted by bridge 

owners. 

• More field-collected long-term-performance data on the performance of FRP pile repair 

is needed. Best practices and guidance for FRP pile repair were not established. 

• More research is needed into steel pile lifecycle corrosion management planning.

• More research is needed into using special materials (e.g., corrosion-resistant and 

ultra-high performance materials) for pile construction and preservation. 
37 

CHAPTER 5. RESEARCH TOPICS

The author proposes the following research topics to cover the gaps identified in chapter 4. 

CORROSION EVALUATION, PREVENTION, AND MITIGATION FOR BRIDGE 

PRESERVATION

Based on the identified gaps, the following research topics are proposed: 

• Performance and preservation needs for corrosion-resistant rebar (e.g., stainless steel, 

CFRP/GFRP, chromium alloy steel, continuously galvanized rebar (CGR) and duplex 

coating rebar)-reinforced bridge components and elements (e.g., decks, superstructures, 

substructures, and piles) (C1*

).

• Identification of performance and preservation needs for bridge components and elements 

with duplex coatings (C2*

).

• Assessments of cost, performance, and service life extension of corrosion protection, 

prevention, and mitigation techniques (C3*).

• Impacts of climate change on corrosion initiation and development and the effects on 

bridge preservation and management decisionmaking. 

• Cathodic protection for bridge decks, superstructures, substructures, and piles; 

determination of best practices; and creation of guidelines.

• Live-load effects on bridge corrosion initiation and propagation and their impacts on 

bridge preservation and management decisionmaking. 

• Use of NDE/SM data to enhance early detection of corrosion initiation and propagation 

and facilitate early corrosion prevention intervention. 

• Identification of performance matrix and testing methods to measure the effectiveness of 

corrosion prevention and mitigation techniques.

DATA FOR BRIDGE PRESERVATION

Based on the identified research gaps, the following research topics applying element data, 

NDE/SM data, and other data in bridge preservation and management are proposed. 

*

Topic identities in table 1.
38 

Element Data in Bridge Preservation and Management

The following are identified topics for element data:

• Evaluation of ADE and determination of its potential for adoption as NBE or BME.

• Element-based defect-reporting framework that includes damage location information.

• Development of an element data framework to accept BIM and digital as-built data that 

provide improved information for preservation and management decisionmaking (D4*

).

NDE/SM Data in Bridge Preservation and Management

Following are identified topics for NDE/SM data:

• Development of bridge preservation planning, project costs, and quantity estimations for 

bridges, with and without NDE/SM data (D1*).

• Integration of construction and sensing data (e.g., light detection and ranging (LiDAR), 

UAV, and NDE/SM data) into 3D bridge models or digital as-builts to facilitate more 

efficient and effective bridge preservation and management decisionmaking (D2*).

• AI-based and big-data-based approaches for NDE/SM data analysis that support effective 

bridge preservation and management decisionmaking. 

• Use of WIM data, NDE/SM data, and inventory data to determine the live-load effect on 

the performance of bridge components or elements and preservation decisionmaking. 

• Use of NDE/SM data to enhance early deterioration modeling and improve preservation 

and maintenance decisionmaking (D3*

).

• UAV, unmanned water vehicle, and unmanned ground vehicle data in bridge preservation 

and asset management decisionmaking. 

• The possibility of collecting NDE or other sensing data from deck bottoms (e.g., via 

UAV) and the use of such data in deck preservation and management decisionmaking. 

Other Data for Bridge Preservation and Management

Following are identified topics for other data:

• Development of a bridge maintenance data collection framework to understand bridge 

preservation activities (D5*

).

• Evaluation of potential bridge preservation applications using currently available but 

underused data (D6*).

*

Topic identities in table 1.
39 

• Identification of data needs for post-extreme-event bridge repair or rebuild 

decisionmaking (D7*

).

BRIDGE PRESERVATION AND MANAGEMENT OF LIFECYCLE PLANNING

Based on identified gaps, research topics are proposed for cost modeling, deterioration modeling, 

and decision making. 

Cost modeling

Following are topics for cost modeling:

• Lifecycle cost savings due to adopting new materials and new technologies in bridge 

preservation (P4*).

• Quantification of the effects of bridge preservation activities (P2*).

Deterioration modeling

Following are topics for deterioration modeling:

• Development of element and health-index-based deterioration modeling (P3*).

• Live-load effects on bridge performance and impacts on preservation and management 

decisionmaking (P5*).

• Deterioration modeling that considers the impacts of climate change and other 

environmental factors.

• Deterioration model of structural capacity (load-rating deterioration modeling). 

• Bridge resilience and how it affects bridge preservation and asset management 

decisionmaking. 

Decisionmaking

Following are topics for decisionmaking:

• Methods to integrate risk assessment into bridge preservation and management 

decisionmaking (P1*

).

• Quantification of the effects of bridge preservation activities through accelerated 

laboratory testing, field testing, and inventory data analysis (P2*).

• Bridge preservation decisionmaking that considers environmental costs and resilience. 

*

Topic identities in table 1.
40 

• Performance-based and risk-based bridge preservation and management planning. 

• Network-level and lifecycle bridge preservation and management planning. 

ECOFRIENDLY AND SUSTAINABLE MATERIALS AND TECHNOLOGIES FOR 

BRIDGE PRESERVATION AND REPAIR

Based on the identified gaps, the following research topics are proposed: 

• Sustainable and innovative techniques and materials for bridge and tunnel preservation or 

repair (S1*

).

• Consideration of environmental costs of bridge preservation and asset management 

decisionmaking and planning. 

• Preservation techniques to improve bridge resilience and protect bridges from natural and 

man-made hazards.

BRIDGE DECK PRESERVATION AND MANAGEMENT

Based on the identified gaps, the following research topics are proposed: 

• Identification of standard tests for quality assurance and performance evaluation of deck 

preservation activity (B1*

).

• Performance of UHPC overlays:

• Accelerated testing data.

• Field data.

• Validation and calibration of testing data with field data.

• Use of testing data to predict performance.

• LCCA.

• Bridge deck lifecycle preservation and management planning. 

• Performance of fiber-reinforced concrete for bridge deck and deck overlay (B2*

).

• Ecofriendly materials and techniques for bridge deck preservation and repair.

• Live-load effects on bridge deck performance and impact on preservation and 

management decisionmaking. 

*

Topic identities in table 1.
41 

• Impact of climate change on bridge deck performance, preservation, and improvement in 

decisionmaking.

PRESERVATION OF SUPERSTRUCTURE AND SUBSTRUCTURE

Based on the identified gaps, the following research topics are proposed: 

• Identification of performance matrix and testing methods to measure the effectiveness of 

bridge substructure and superstructure preservation techniques. 

• UHPC shotcrete for bridge superstructure and substructure preservation (B4*

).

• Case study for beam end repair of prestressed concrete beams, steel girders, and other 

beams.

• Early deterioration and damage detection and treatment and prevention of deterioration 

and damage of substructures. 

• Fire damage monitoring, reporting, repair, and prevention (B5*).

• Vehicle and vessel collision monitoring, reporting, repair, and prevention (B5*).

• Identification of effective approaches to substructure and superstructure preservation 

(B6*).

PRESERVATION OF BRIDGE PILES

Based on the identified gaps, the following research topics are proposed: 

• Impact of environmental factors and live load on bridge pile performance, preservation, 

and management decisionmaking. 

• Bridge pile lifecycle preservation and management planning (B6*).

• Performance and preservation needs of UHPC piles and LCCA. 

• Performance and preservation needs of FRP pile in marine environments and LCCA. 

• Case study for FRP repair of bridge pile.

• Underwater NDE robot or SM systems for pile performance evaluation and integration of 

data into pile preservation decisionmaking. 

• SM for the performance of deteriorated or damaged piles and use of data in management 

decisionmaking. 

*

Topic identities in table 1.
42 

• Identification of performance matrix and testing methods to measure the effectiveness of 

pile preservation techniques.

PRESERVATION OF WATERTIGHT JOINTS

Based on the identified gaps, the following research topics are proposed: 

• Guidelines for link slab design, construction, inspection, and preservation (B3*

).

• Case study, best practices, performance measurements, deterioration modeling, and 

LCCA for the following: 

o Expansion joints. 

o Link slab (guidelines for design, construction, and performance evaluation). 

o Joint elimination (semi-integral abutment, link slab, etc.) and jointless bridges. 

o Longitudinal joints.

With the comments from the FHWA internal review, the author selected high-priority topics, 

which are shown in table 1. 

Table 1. High-priority bridge preservation research topics.

Category Topic ID Topic

Planning 

P1 Develop methods to integrate risk assessment into bridge 

preservation and management decisionmaking. 

P2 Quantify the effects of bridge preservation activities.

P3 Develop element- and health-index-based deterioration models. 

P4 Assess LCCA and performance of new materials and new 

technologies in bridge preservation.

P5 Evaluate live-load effects on bridge performance and how they 

affect preservation and management decisionmaking.

Data

D1 Develop bridge preservation planning, project costs, and quantity 

estimations for bridges, with and without NDE/SM data. 

D2

Integrate construction and sensing data (e.g., LiDAR, UAV, and 

NDE/SM data) into 3D bridge models or digital as-builts to 

facilitate more efficient and effective bridge preservation and 

management decisionmaking. 

D3 

Develop methods to leverage NDE/SM data to enhance early 

deterioration modeling and improve preservation and maintenance 

decisionmaking.

D4

Develop an element data framework that accepts BIM and digital 

as-built data and provides enhanced information for preservation 

and management decisionmaking.

*Topic identities in table 1.
43 

Category Topic ID Topic

D5 Develop a bridge maintenance database framework.

D6

Identify available but underused data and evaluate the data’s 

potential benefit in bridge preservation and management 

decisionmaking.

D7 Identify unique data needs for post-extreme-event bridge repair or 

rebuild decisionmaking. 

Sustainability S1 Develop or identify sustainable techniques and materials for bridge 

preservation and repair.

Corrosion 

C1

Identify performance and preservation needs for corrosion-resistant 

rebar (e.g., stainless steel, CFRP/GFRP, MMX, CGR, epoxy 

coated, and new textured epoxy rebar), reinforced bridge 

components and elements (e.g., deck, superstructure, substructure, 

and piles).

C2 Identify performance and preservation needs for bridge components 

and elements with duplex coatings.

C3 Assess cost, performance, and service life extension of corrosion 

protection, prevention, and mitigation techniques.

Preservation 

of bridge 

components 

B1

Identify evaluation methodology (including standard tests) and data 

framework for quality assurance and performance evaluation for 

deck preservation activities.

B2 Evaluate the performance of fiber-reinforced concrete for bridge 

decks and deck overlays.

B3 Develop guidelines for link slab design, construction, inspection, 

and preservation.

B4 Assess UHPC shotcrete or other applications for bridge 

preservation.

B5 Develop methods to monitor, report, repair, and prevent fire 

damage and vehicle and vessel collisions.

B6 Evaluate techniques for the preservation of bridge piles, 

substructures, and superstructures.

B7 Develop performance criteria, corrective actions, and optimization 

for bridge approach systems.

45 

CHAPTER 6. REVIEW AND RANKING

A draft of this document went through FHWA internal and external review, and the author 

collected feedback. The following describes the review and feedback collection procedure: 

• The first draft of the roadmap was sent for review to engineers in FHWA’s Office of 

Infrastructure Research and Development, the FHWA senior bridge preservation 

engineer, the FHWA senior bridge management engineer, and all team leaders of FHWA 

structure disciplines. The draft was revised to address their comments, and a list of 

high-priority bridge preservation research topics was created. The updated version was 

sent to the same group of FHWA personnel for further followup. 

• The revised draft was sent for external review. A small WG consisting of BPETG 

members was formed to conduct the first round of external review. The author received 

and incorporated the WG’s input regarding topic grouping and ranking. 

The third draft version was distributed to members of the TSP2 national deck 

preservation WG members, the AASHTO Bridge Preservation Technical Subcommittee 

(T-9), and FHWA BPETG for final external review. Presentations were given to the TRB 

Bridge Preservation Committee (TRB AKT60), AASHTO T-9, the small WG, and 

FHWA BPETG to collect feedback. FHWA BPETG members were asked to select their 

top three topics from the high-priority project list. Fifteen responses were received. 

Collective responses showed interest in the following 13 topics, in priority order: 

1. P2: Quantify the effects of bridge preservation activities.

2. P1: Develop methods to integrate risk assessment into bridge 

preservation/management decisionmaking.

3. D5: Develop an NBMD framework. Develop a bridge maintenance data collection 

framework to understand bridge preservation activities. 

4. B1: Identify evaluation methodology (including standard tests) for quality assurance 

and performance evaluation for deck preservation activities.

5. P4: Assess the LCCA and performance of new materials and new technologies in 

bridge preservation. 

6. D3: Leverage NDE/SM data to enhance the early deterioration modeling and improve 

preservation/maintenance decisionmaking. 

7. C1: Identify performance and preservation needs for corrosion-resistant rebar (e.g., 

stainless steel, CFRP/GFRP, MMX, CGR, black rebar, epoxy coated, new textured 

epoxy rebar)-reinforced bridge components/elements (e.g., deck, superstructure, 

substructure, and piles). 
46 

8. C3: Assess cost, performance, and service life extension of corrosion protection, 

prevention, and mitigation techniques. 

9. P5: Evaluate the live-load effects on bridge performance and how they impact 

preservation and management decisionmaking. 

10. B6: Evaluate techniques for preserving bridge piles, substructures, and 

superstructures.

11. P3: Develop element and health-index-based deterioration models.

12. D2: Integrate construction and sensing data (e.g., LiDAR, UAV, NDE/SM data) into 

3D bridge models or digital as-builts to facilitate more efficient and effective bridge 

preservation and management decisionmaking. 

13. D4: Develop an element data framework to accept BIM and digital as-built data that 

provide improved information for preservation and management decisionmaking. 

A priority score for each topic was calculated for the top three topics received in the voting, and 

the preceding list shows the computed priorities. However, due to the limited number of votes 

received, the rankings may not be accurate. Research with an immediate application received 

more interest. Topics not receiving priority interest are typically more innovative and may be 

associated with relatively higher risk. If aligned well with organizational strategic goals, an 

innovative, high-risk project also could be an important component of the research portfolio. 
47 

CHAPTER 7. STATEMENT FOR SELECTED TOPICS

The author developed short descriptions of the topics shown in table 1. Table 2 shows the 

statements for the 10 topics that were rated higher by BPETG and other stakeholders. 

Descriptions of other topics can be found in the appendix. 

AASHTO made a 2024 NCHRP project selection recently. The project, called Incorporate Risk 

Management in Maintenance Practice (NCHRP 23-38), may cover some aspects of topic P1.(50)

NCHRP 20-05 (Topic 55-01 State DOT Use and Policies on Implementation of Corrosion 

Resistant Reinforcing Bars), covers some parts of topic C1.(51) NCHRP 20-05 originated from 

topic C1 and ranked high in the stakeholders’ top 10 list. Close followup of those two NCHRP 

projects is necessary to avoid duplicate research and identify new research needs as practical.

Consider the similarities and correlations between topics D2, D3, and D4, which have been 

combined into a topic called Leverage Digital As-Built, Operational, and Sensing Data to Bridge 

Preservation and Management. The combined project will identify data needs for bridge 

management; evaluate the data source, collection costs, data management, and interface with 

bridge management systems; and manage automated data integration and model updating to 

optimize bridge management decisionmaking in a BIM-compatible way. The project can be part 

of FHWA infrastructure digitization (e.g., digital as-built, digital twin, and BIM) efforts.

Table 2. Statements for the top 10 research topics.

ID Topic Short Statement

Estimated 

Project 

Duration

D5

Develop a bridge 

maintenance data 

collection framework to 

understand bridge 

preservation activities.

• Conduct a survey for the state of 

practice of maintenance data 

collection.

• Improve the efficiency and 

effectiveness of data collection, 

sharing, and utilization with a 

consistent data framework. 

• Develop guidelines for maintenance 

data collection by analyzing existing 

State-collected data and updating the 

NCHRP 14-15 framework to reflect 

new NBI and BIM requirements.(47,7)

• Develop a tiered data collection 

strategy so stakeholders can collect 

data at a minimum level or include 

more data.

• Understand bridge preservation 

activities from collected data. 

2–3 yr 
48 

ID Topic Short Statement

Estimated 

Project 

Duration

P2

Quantify the effects of 

bridge preservation 

activities.

• Select activities for this study.

• Collect/acquire bridge 

preservation/maintenance data and 

testing data if available.

• Evaluate the benefits of the activities 

through inventory data analysis, 

accelerated laboratory testing, and 

field testing.

• Evaluate the lifecycle cost (in terms of 

financial and environmental costs, if 

possible) for each activity.

3 yr 

Combined 

D2, D3, 

and D4 

Leverage digital as-built, 

operational, and sensing 

data in bridge 

preservation and 

management 

decisionmaking. 

• Define the bridge asset management 

workflow and data needs. 

• Determine the data sources and data 

collection cost associated with each 

data requirement. 

• Optimize the data items for bridge 

preservation/management 

decisionmaking through cost-benefit 

evaluation. 

• Make the identified data items 

available or accessible for bridge 

management systems. BIM 

compatibility will also be studied. 

• Automate the data-leveraging 

procedure. 

• Conduct a pilot case study to 

demonstrate the work.

3 yr 

B1

Develop a quality control 

procedure and 

performance evaluation 

of bridge preservation 

activities.

• Establish quality control procedures 

and performance evaluation 

procedures for bridge preservation 

activities.

• Research and develop guidelines for 

quality control procedures and 

performance evaluation procedures 

for selected preservation activities.

3 yr 
49 

ID Topic Short Statement

Estimated 

Project 

Duration

P4

Assess the lifecycle cost 

and performance of new 

materials and new 

technologies in bridge 

preservation.

• Identify new materials and new 

technologies for study. 

• Collect/acquire cost data for new 

materials and new technologies.

• Develop lifecycle preservation plans 

that use new materials and new 

technologies based on LCCA. 

2–3 yr 

P5

Evaluate live-load effects 

on bridge performance 

and how they affect 

preservation 

decisionmaking. 

• Identify live-load impacts on bridge 

performance, which is important due 

to the ever-increasing truck weight, 

next generation trucks and truck 

operation. 

• Investigate how WIM data can be 

used to establish general and bridge 

specific live load model

• Investigate how to quantify live-load 

effect on bridge deck deterioration, 

fatigue service life, and capacity etc. 

through analysis and/or field testing 

which may involve NDE/SM data and 

inventory data 

• Investigate preservation activities that 

are more effective for heavy loadcaused deterioration. 

• Investigate preservation and 

management decisionmaking 

strategies considering live load 

effects

• Demonstrate the work with one or two 

case studies

2–3 yr 

C1*

Identify performance and 

preservation needs for 

corrosion-resistant rebar 

(e.g., stainless steel, 

CFRP/GFRP, MMX, 

CGR, epoxy coated, new 

textured epoxy rebar) 

reinforced bridge 

components/elements 

(e.g., deck, 

superstructure, 

• Establish a database for bridges with 

corrosion-resistant rebar (starting with 

stainless steel rebar and bridge deck) 

and reinforced components and 

elements. Develop a data dictionary 

and start populating it with data. 

• Determine field performance from 

inventory data or laboratory or 

field-testing data if available.

• Correlate field performance (from 

inventory or field testing) with 
50 

ID Topic Short Statement

Estimated 

Project 

Duration

substructure, and piles). accelerated laboratory-testing data, if 

available, to validate the testing. After 

validation, laboratory testing can be 

used to predict future performance 

data, which is rarely available or 

expensive to collect.

• Collect cost data and perform LCCA 

to show the benefit of using stainless 

steel rebar, GFRP rebar, and other 

corrosion-resistant rebar in bridge 

deck and corrosion-prone zones. 

• Recommend using the stainless-steel 

rebar type in bridge deck, 

superstructure, and substructure. 

Investigate maintenance needs, if any.

• Quantify the benefit of using 

corrosion-resistant rebar in service life 

design.

B6

Evaluate techniques for 

the preservation of bridge 

piles, substructures, and 

superstructures.

• Identify effective preservation 

techniques through a literature review. 

• Conduct an indepth survey/interview 

with bridge owners to document the 

state-of-practice procedure.

• Conduct LCCA if practical. 

• Identify and document best practices.

2–3 yr 

P1* 

Develop methods to 

integrate risk assessment 

into bridge preservation 

and management 

decisionmaking. 

• Develop a risk evaluation framework 

that includes or facilitates the 

following:

o Investigate bridge 

deterioration-caused risks.

o Investigate climate change (e.g., 

changes in temperature, 

precipitation, freeze–thaw 

cycle)-caused risks.

o Evaluate extreme events (e.g., 

hurricane, wildfire, flood, 

earthquake)-caused risks. 

o Investigate the combined 

multihazard risk.

• Investigate bridge resilience and 

sustainability.

• Develop a data collection framework 

for before, during, and after event 

3 yr 
51 

ID Topic Short Statement

Estimated 

Project 

Duration

condition evaluation. Sensing 

technologies are needed in data 

collection.

• Investigate and develop a risk-based 

preservation and management 

decisionmaking framework and 

demonstration tool. AI and big-data 

approaches can be used.

C3**

Assess the costs, 

performance, and service 

life extensions of 

corrosion protection, 

prevention, and 

mitigation techniques. 

• Identify corrosion protection, 

prevention, and mitigation 

technologies (e.g., galvanic coating, 

cathodic protection) to be studied. 

• Collect cost and performance data.

• Conduct a case study to develop 

practice guidelines for identified 

techniques.

3 yr 

*Recently funded project NCHRP 23-38 is closely related to topic P1. FHWA will follow up to avoid duplicate 

research and identify new needs as practical.(50)

**More specific research needs will be identified after the report on FHWA corrosion peer exchange is available.(51)

53 

CHAPTER 8. CONCLUSIONS

As State DOT bridge preservation programs mature and more bridges in poor condition get 

replaced, proactive bridge preservation is becoming a cost-effective tool for maintaining the 

bridge inventory in a state of good repair. In the meantime, considering service life during bridge 

design and balancing bridge rehabilitation and replacement are also important preservation 

decisions. Increasing knowledge of bridge preservation materials, technologies, and 

decisionmaking strategies is becoming more helpful in optimizing limited funds. This roadmap 

represents a strategic approach to bridge preservation research needs for FHWA and may also be 

used by other agencies or organizations. In addition to addressing research gaps, this roadmap 

addresses emerging technologies and innovative techniques. This roadmap is a living document 

and will be updated periodically to reflect completed work and new research needs. 

55 

APPENDIX. STATEMENTS FOR OTHER TOPICS 

In table 3, short descriptions were developed for high-ranking topics that were not selected for 

the top 10 list. 

Table 3. Statements for other topics.

ID Topic Short Description

P3

Develop health-indexbased and risk-based 

deterioration models for 

bridge preservation 

decisionmaking. 

• Conduct a literature review and case study.

• Compile AASHTO element or component data from 

NBI.(7)

• Develop a health index from element data (consider 

including extra data).

• Develop element-based and health index-based 

deterioration models using AI and big-data approaches.

• Investigate if risk-based deterioration models are 

practical.

• Investigate the framework for integrating NDE/SM 

data into element-based deterioration modeling 

(optional).

D3

Develop methods to use 

NDE/SM data to enhance 

the early deterioration 

modeling and improve 

preservation and 

maintenance 

decisionmaking. 

• Research NDE/SM techniques (including load testing) 

that are effective for enhanced condition evaluation, 

especially for early damage and deterioration detection. 

• Improve preservation and maintenance decisionmaking 

by integrating NDE/SM data into the decision 

procedure. 

D2

Integrate construction or 

sensing data (e.g., LiDAR, 

UAV, NDE/SM data) into 

3D bridge models or digital 

as-builts to facilitate more 

efficient and effective 

bridge preservation and 

management 

decisionmaking. 

• Integrate bridge construction data (including cost and 

sensing data) into the project information model to 

obtain digital as-builts.

• Develop workflow and an information delivery manual 

for BIM-based bridge asset management framework.

• Develop a process to update the project information 

model with sensing data (e.g., NDE/SM data, UAV 

data, and LiDAR data). 

• Use model in preservation, management, and postevent 

decisionmaking. 

• Determine lifecycle cost savings due to adoption of 

BIM-based design, construction, and asset 

management approaches.
56 

ID Topic Short Description

D4

Develop an element data 

framework to accept BIM 

and digital as-built data 

that provide improved 

information for 

preservation and 

management 

decisionmaking.

• Develop a data framework that provides more 

element-data information (e.g., report damage 

systematically).

• Allow seamless BIM or digital twin model updating for 

any element data update. 

D1

Develop bridge 

preservation planning, 

project cost, and quantity 

estimation for bridges—

with and without NDE/SM 

data.

• Investigate how deterioration models can be improved 

by NDE/SHM data. 

• Investigate network-level bridge preservation planning 

for bridges with and without NDE/SHM data. 

• Investigate how NDE/SHM data can improve 

preservation planning at the project level.

D6

Identify available but 

underused data and 

evaluate the data’s 

potential benefit in bridge 

preservation and 

management 

decisionmaking. 

• Incorporate data currently collected by State DOTs or 

FHWA programs or projects. Many bridge 

preservation engineers are not aware of this data, and 

therefore, such data are not fully used in bridge 

preservation decisionmaking: 

o Design and construction data (digital as-built).

o HPMS, such as WIM data.

o Traffic data and collision data.

o Climate data.

o Other data to be identified. 

• Collect bridge damage and deterioration reported by 

the public on social media sites (may consider 

establishing a system for the public to report this type 

of finding in the future).

• Evaluate the data to determine their applications in 

bridge preservation decisionmaking. 

• Develop a decisionmaking tool that uses the identified 

data.

• Evaluate the results and benefits.

D7

Identify unique data needs 

for post-extreme-event 

bridge repair, 

rehabilitation, or rebuild 

decisionmaking. 

• Investigate the data (e.g., UAV data and other 

remote-sensing or image data) need for post 

extreme-event bridge condition evaluation and repair, 

rehabilitation, or rebuild decisionmaking. 

• Investigate the data application approaches.

• Evaluate the improvement (e.g., cost saving) by using 

the data.

• Develop a decision tool that involve using the 

identified data.
57 

ID Topic Short Description

S1

Identify sustainable 

techniques for bridge and 

tunnel preservation and 

repair.

• Investigate sustainable materials and techniques that 

can be used for bridge and tunnel preservation and 

repair.

• Develop case studies and guidelines for applying 

identified materials and techniques.

• Perform LCCA and lifecycle emission analysis. 

C2

Identify performance and 

preservation needs for 

bridge components and 

elements with duplex 

coating rebar. 

• Investigate the field performance of the coating 

systems of the 80 or so bridges in the United States 

known to have duplex coatings.

• Identify potential maintenance needs. 

• Perform LCCA.

B2

Evaluate the performance 

of fiber-reinforced concrete 

for bridge decks and deck 

overlays. 

• Evaluate fiber-reinforced concrete because it shows 

potential in solving the problem of deck cracking, a 

common problem of bridge decks. 

• Investigate the performance of fiber-reinforced 

concrete deck or overlay. 

• Investigate the possibility to use steel fiber to facilitate 

EV charging.

B3

Develop guidelines for link 

slab design, construction, 

inspection, and 

preservation.

• Link slab has shown advantages in extending deck 

service life. A national policy or guideline has not yet 

been developed. 

• Investigate the underused technology of link slab and 

its performance.

• Perform LCCA to justify the value of the technology.

B4

Assess UHPC shotcrete or 

other applications for 

bridge preservation. 

• Conduct a literature review for UHPC shotcrete 

applications and interview selected early adopters.

• Evaluate UHPC shotcrete material characteristics and 

application procedures.

• Evaluate the performance of UHPC shotcrete for 

preservation of bridge components. 

B5

Develop methods to 

monitor, report, repair, and 

prevent fire damage and 

vehicle and vessel 

collisions. 

• Develop the data framework and reporting procedure 

for fire and collision events.

• Investigate sensing and prevention systems for fire and 

collision events. 

• Investigate fire damage repair and prevention 

technologies. 

• Investigate collision damage repair and prevention 

technologies.
58 

ID Topic Short Description

B7

Develop performance 

criteria, corrective actions, 

and optimization for bridge 

approach systems.

• Investigate current bumps at bridge entrances/ends, 

which are common, especially for bridges with stub 

abutments. The bumps can cause larger live-load 

impact and discomfort for drivers and passengers. 

• Conduct a study for best design and construction 

practice to reduce bump formation.

• Develop the specification of performance criteria for 

bridge approaches and how to achieve the desired 

performance through cost-effective design, 

construction, and maintenance practices.

• Recommend early preservation intervention activities 

and their effects.

*Recently funded NCHRP synthesis topic 55-01 is similar to topic C1.(52) FHWA will follow up to avoid duplicate 

research and identify new needs.
59 

ACKNOWLEDGMENTS

The author appreciates the help provided by the following: 

• The FHWA Research Library staff for their great efforts in providing literature review 

results always ahead of schedule. AASHTO Technical Committees on Bridge 

Preservation (T-9), Bridge Management, Evaluation and Rehabilitation (T-18), TSP2, 

TRB Standing Committees on Bridge Preservation (AKT60), Bridge and Structures 

Management (AKT50), and Structures Maintenance (AKT40) for helpful and insightful 

feedback.

• FHWA BPETG and Roadmap Development WG for very helpful feedback. 

• FHWA internal reviewers for spending lots of time on the draft review.

61 

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Recommended citation: Federal Highway Administration,

FHWA Bridge Preservation Research Roadmap 

(Washington, DC: 2024) https://doi.org/10.21949/1521789