The FHWA 2015

R T Story

Research and Innovative Solutions for the Nation’s Highway Challenges

&
A century ago, research and technology (R&T) played 

a primary role and led to the conversion of unpaved 

to paved roads with asphalt and concrete pavement 

materials, an innovation that led to greater and safer 

mobility on our Nation’s highways. 

The value of research is seen in the development of large and small 

innovations in materials, designs, policies, operations, and safety on the 

highway system. Deployment of those innovations enables the highway 

system to move people and freight efficiently and contributes to the 

economic success of the United States (U.S.). Today, as in the past, 

researchers and inventors continue to develop innovations and solutions 

to transportation challenges.

The Federal Highway Administration (FHWA) plays a key role in 

leading the national transportation research needed to meet the challenges 

now and in the future. Collaborating with partners around the world, 

FHWA research conducted at its Turner-Fairbank Highway Research 

Center (TFHRC) is improving the roads and bridges we travel on every 

day, saving lives, reducing congestion, and advancing economic growth. 

From connected vehicles and vehicle-to-infrastructure communications to 

road and bridge design, to policy decisions requiring quality transportation 

data, to human factors and environmentally sustainable roads, this is a 

time of boundless opportunity. What was once dreamed of as the highway 

of the future is becoming our reality today. And today we are moving toward 

solutions that will positively impact the transportation system of tomorrow. 

In the many innovations described here, learn how FHWA’s R&T 

initiatives are contributing to advancements in the transportation system.

Michael F. Trentacoste

Associate Administrator for Research, Development, and Technology
Table of Contents

Introduction

1 Telling the FHWA 2015 R&T Story

The Key Challenges

6 Advancing Safety

12 Improving the Mobility of People and Goods

16 Preserving the Nation’s Infrastructure

22 Enhancing System Performance

26 Promoting Environmental Sustainability

32 Preparing for the Future

Conclusion

39 Research Moves the Nation Forward

Cover: Solar walkway image source: ©Jon Pece/www.rockethorse.com. All other images: FHWA

Opposite page, portrait of Associate Administrator Trentacoste: FHWA
Construction of detour bridges at this location was impossible since these 

bridges were only a short distance (50 to 70 feet) from either end of the 

Elk Creek Tunnel in Oregon. With these severe limitations, the only viable 

alternative available was to remove and replace the bridges using 

hydraulic sliding system (HSS), an innovative rapid bridge replacement 

technique. (Image source: FHWA)
Federal Highway Administration 1 

Telling the FHWA 

R&T Story 

Introduction

The U.S. has built one of the 

world’s greatest transportation 

systems. With more than 600,000 

bridges and 8.5 million lane miles, 

the system is large, complex, 

and aging.1

 

U.S. transportation agencies are challenged to make the 

system more efficient using existing infrastructure and 

funding resources, while improving travel times and safety. 

The goal of transportation research is to develop solutions to 

the Nation’s most pressing challenges and find transformative 

opportunities that will meet future needs. 

The responsibility of the federal government is to fund and 

conduct R&T activities of national interest that will lead 

to finding solutions to highway transportation issues and 

significantly advance technology innovation with a clear 

public benefit when private investment is neither present 

nor sufficient. FHWA coordinates with State departments 

of transportation (DOTs), and local agencies, industry, and 

academia because, in addition to conducting research, those 

agencies are responsible for deploying and implementing 

The U.S. highway 

transportation system 

is called the backbone 

of America because 

the Nation’s economic 

future depends on its 

ability to efficiently and 

safely move people and 

goods across the country.
2 The FHWA 2015 R&T Story: Research and Innovative Solutions for the Nation’s Highway Challenges

research products and innovations on State and local 

transportation systems.2

This FHWA 2015 R&T Story presents some of the 

national highway transportation challenges, and 

discusses how the research and innovations conducted 

or sponsored by FHWA address these challenges 

and contribute to changes and improvements in the 

transportation system. This document also highlights 

a variety of research projects and activities that 

demonstrate FHWA’s positive and long-lasting 

impact on the national highway transportation system. 

Highlighting Impacts of Research

• FHWA developed geosynthetic reinforced soilintegrated bridge system (GRS-IBS) technology. 

This accelerated bridge construction method for 

bridges saved State DOTs millions of dollars 

(15 to 60 percent in construction and design costs) 

and significantly reduced construction time—

thereby minimizing construction zone closures 

and inconvenience to drivers.

• FHWA investigated “Safety EdgeSM” technology 

to determine whether tapering the edge of a road 

would help drivers to navigate back on the road. 

According to the 3-year crash analysis, the 

benefits outweighed the costs by as much as 

63 to 1. Most importantly, Safety Edge can 

contribute to saving lives by reducing the 

potential for rollovers and other severe crashes.

• Brought to the U.S. by FHWA, use of warminstead of hot-mix asphalt reduces fuel consumption, greenhouse gas emissions, and paving costs, 

while extending the paving season and potentially 

improving compaction. To date, 41 State DOTs 

and all Federal Lands Highway divisions have 

specifications for using warm-mix asphalt. In 

2013, warm-mix asphalt is estimated to have 

reduced emissions by 2 million tons (the equivalent of removing 200 thousand vehicles off the 

roads). And to expand on the environmental 

benefits, FHWA is conducting additional research 

to develop well-founded guidance for using warmmix asphalt in combination with a high content 

of recycled materials, such as reclaimed asphalt 

pavement, to achieve durable pavements.

• FHWA’s research provided the details for 

connecting Prefabricated Bridge Elements and 

Systems and knowledge on Slide-in Bridge 

Construction to enable State DOTs to shorten 

the time needed for work zones and road closures.

This finished 7-inch whitetopping surface with pavement marking was completed as part of an FHWA Highways for LIFE supported pavement 

rehabilitation with North Dakota DOT. (Image source: FHWA)
Federal Highway Administration 3

• FHWA transitioned a good idea into a great 

idea by furthering the development of the 

diverging diamond interchange (DDI), a new 

method of navigating through busy highway 

intersections, which improves safety for motorists 

and pedestrians at highway interchanges while 

reducing congestion.

• FHWA developed a Project Finance Primer to 

help agencies compare various approaches to 

planning and delivering expensive construction 

projects, such as evaluating the difference 

between funding projects through conventional 

design-bid-build projects or using public-private 

partnerships. 

• FHWA promotes innovation development with 

small businesses:

• Migma Systems developed a new stereovisionbased approach for detecting pedestrians at 

intersections. Based on a concept borrowed 

from military tracking, the company used a 

new light-emitting diode (LED) stereo camera 

and advanced pedestrian-detection algorithms 

to distinguish pedestrians and vehicles on the 

roadways. Information from the project can be 

used in connected-vehicle research to greatly 

reduce pedestrian fatalities. 

• Solar Roadways envisions replacing current 

asphalt or concrete surfaces with modular solar 

road panels: structurally engineered solar panels 

that replace conventional paving on roadways. 

The intent of the research is to demonstrate 

the potential for developing structural pavement 

panels that can convert solar radiation to 

electricity and disseminate the power to meet 

local electricity demands.

The full impact of transportation research and 

innovations is usually realized over years or decades 

as the products are implemented across the transportation system and advance the state of the practice. 

Research results, when implemented appropriately, 

can save millions of dollars, save lives, extend the 

life of highway infrastructure, reduce congestion, 

improve travel time, increase productivity, and 

positively affect the environment. FHWA’s research, 

guidance, and efforts provide State DOTs and local 

agencies with the leadership and support needed to 

address new and shifting challenges. 

Showcasing Research of National Significance 

through the FHWA R&T Agenda

Within FHWA, hundreds of research projects are 

underway to develop innovations and solve the 

country’s pressing transportation problems. Because 

transportation comprises many disciplines, from 

human factors to structural engineering to 

environmental and safety planning and engineering, 

an extensive depth and breadth of knowledge is 

necessary to address the challenges facing our 

transportation system.

The FHWA R&T Agenda was developed to 

communicate a comprehensive plan for the Agency. 

The plan provides a collaborative platform to address 

national transportation challenges and transparency 

into research activities. Stakeholder input also 

enables a deeper understanding of the challenges and 

issues at the local and State levels.

FHWA’s bridge replacement research has reduced construction 

times, decreasing congestion and increasing the mobility of goods 

and passenger travel. (Image source: FHWA)
4 The FHWA 2015 R&T Story: Research and Innovative Solutions for the Nation’s Highway Challenges

The FHWA 2015 R&T Story provides a framework 

for how FHWA research will meet six of the Nation’s 

high-priority highway challenges: 

• Advancing Safety Toward Zero Deaths—

a highway system free of fatalities.

• Improving the Mobility of People and Goods—

moving people and goods, reliably and safely, to 

where they need to go.

• Preserving the Nation’s Infrastructure—keeping 

pavements, bridges, and structures in good 

condition.

• Enhancing System Performance—decreasing 

highway congestion, safety risks, and wear-andtear on roadways.

• Promoting Environmental Sustainability—

improving public health, enhancing the 

environment, and conserving natural resources.

• Preparing for the Future—transforming big ideas 

into the innovations of tomorrow.

Addressing these six challenges requires the cooperation and collaboration of numerous stakeholders in 

the public and private sectors, academia, industry, and 

the international community. FHWA has developed 

partnerships with many of these stakeholders, offering 

a way for transportation stakeholders to become 

involved with and contribute to developing a stronger 

transportation network. 

The remainder of this FHWA 2015 R&T Story highlights six key challenges facing the Nation’s transportation network, and demonstrates how FHWA R&T 

solutions advance the Nation’s mobility, well-being, 

and economic security. 

Leading Highway Research Across 

the Globe

A Culture of Innovation at Turner-Fairbank 

Highway Research Center

FHWA’s Turner-Fairbank Highway Research Center 

(TFHRC) in McLean, VA, plays a vital leadership 

role in developing and implementing coordinated 

highway R&T with other research entities within the 

U.S. and internationally. 

TFHRC houses more than 20 laboratories, data 

centers, and support facilities; and conducts and 

sponsors applied and exploratory advanced research 

on vehicle-highway interaction, nanotechnology, 

safety, pavements, bridges and other highway 

structures, human-centered systems, operations 

and intelligent transportation systems (ITS), and 

materials. Researchers and engineers with expertise 

in a variety of disciplines (e.g., engineering, chemistry, and psychology) support TFHRC’s mission.

TFHRC not only delivers cutting-edge in-house 

research, but also collaborates with a wide range of 

researchers across the Nation and around the world. 

The center’s laboratories provide FHWA, the 

U.S. Department of Transportation (USDOT) modal 

agencies, other Federal agencies, and State DOTs 

and local agencies with vital resources for advancing 

the body of transportation knowledge. TFHRC 

actively engages in formal collaborations with the 

American Association of State Highway and Transportation Officials (AASHTO), the Transportation 

Research Board (TRB), and the Forum of European 

National Highway Research Laboratories. In 

addition, there are informal collaborations with 

researchers in U.S. companies, academia, and other 

federal and local agencies, resulting in joint peerreviewed papers and shared research methods. 

TFHRC also engages in cooperative research and 

development (R&D) agreements with the 

private sector and academia to explore and build new 

highway-related technologies. To work on projects 
Federal Highway Administration 5

of mutual interest, TFHRC hosts visiting researchers 

from a variety of organizations.

Through the National Research Council Research 

Associateship Program, TFHRC sponsors postdoctoral and senior research associates who work 

closely with center staff on research that is relevant 

to FHWA’s challenges and contributes to the associates’ professional development. The program attracts 

skilled associates at the cutting edge in their disciplines, and allows FHWA to focus associates’ talents 

on significant problems. Many associates continue 

working in transportation research and contribute to 

the Agency’s research after finishing the program.

With TFHRC providing research, development, and 

technology management, the FHWA R&T Agenda 

articulates the objectives that guide the Agency’s 

research, development, and deployment activities 

to strengthen and improve the National Highway 

System. The FHWA 2015 R&T Story also identifies 

the strategies that FHWA is pursuing to achieve those 

objectives, and selected activities that target one or 

more of the Nation’s six key highway challenges. 

Take a look at the following research highlights that 

contribute to enhancing and improving the national 

transportation system.

Accelerating Innovation, Every Day Counts

In 2009, FHWA launched Every Day Counts 

(EDC) in cooperation with the AASHTO to speed 

up the delivery of highway projects and to address 

the challenges presented by limited budgets. EDC is 

a State-based model to identify and rapidly deploy 

proven but underutilized innovations to shorten the 

project delivery process, enhance roadway safety, 

reduce congestion and improve environmental sustainability. A key component of implementing new 

technology is nurturing a State-based network for 

the deployment of innovation. To support this concept the FHWA established the State Transportation 

Innovation Council (STIC) Incentive Program and 

the Demonstration Project Program to help States 

institutionalize innovations and meet their innovation deployment goals.

For More Information

The following Web sites provide additional information and further 

highlight the transportation challenges and FHWA activities 

discussed above. 

Geosynthetic Reinforced Soil Integrated Bridge System, 

Synthesis Report: https://www.fhwa.dot.gov/publications/research/

infrastructure/structures/11027/11027.pdf. 

Safety EdgeSM technology: http://www.fhwa.dot.gov/

everydaycounts/technology/safetyedge/intro.cfm. 

Warm Mix Asphalt Technologies and Research: 

http://www.fhwa.dot.gov/pavement/asphalt/wma.cfm. 

Prefabricated Bridge Elements: https://www.fhwa.dot.gov/

everydaycounts/technology/bridges/intro.cfm. 

Diverging Diamond Interchange FHWA YouTube video: 

https://www.youtube.com/watch?v=eLAwwl3EtN4. 

Project Finance Primer: http://www.fhwa.dot.gov/ipd/finance/

resources/general/. 

Small Business Innovation Research (SBIR): http://www.volpe.dot.

gov/work-with-us/small-business-innovation-research. 

AP Story—Inventor Pushes Solar Panels for Roads, Highways: 

http://bigstory.ap.org/article/inventor-pushes-solar-panelsroads-highways. 

Every Day Counts: http://www.fhwa.dot.gov/everydaycounts/.

State Transportation Councils: http://www.fhwa.dot.gov/stic/.

1. Federal Highway Administration (2011). “Our Nation’s Highways: 2011.” 

(Web page) Washington, DC. Accessed online: September 9, 2014. 

(http://www.fhwa.dot.gov/policyinformation/pubs/hf/pl11028/chapter1.cfm)

 2. Transportation Research Board (2008). TRB Special Report 295, The 

Federal Investment in Highway Research, 2006–2009: Strengths and 

Weaknesses. Transportation Research Board, Washington, DC.
6 The FHWA 2015 R&T Story: Research and Innovative Solutions for the Nation’s Highway Challenges

Examples of FHWA research 

and innovation delivery 

activities:

• Improving Data and Tools for Safety 

Analyses

• Improving the Safety of Pedestrians and

Bicyclists

• Analyzing and Testing Roadside Safety 

and Security Barriers

• Looking Ahead Toward Driver Behavior 

Analysis and New Connected Vehicle 

Technology

Above: President Obama visits FHWA’s driving 

simulator. Below: The full-scale driving simulator 

enables FHWA to study drivers in real-world 

conditions. (Images: FHWA) 

Advancing 

Safety

Safety is the U.S. Department of 

Transportation’s (USDOT’s) top priority 

and is underscored throughout FHWA’s 

research areas. 

In 2012, 33,561 people died as a result of motor vehicle 

crashes.3

 While this figure reflects a continuing decline in 

fatalities, even one death is too many. That is why FHWA 

research continues to seek innovative approaches and 

technologies that support the USDOT vision of advancing 

toward zero deaths and serious injuries. 

Highway safety is considered for every FHWA program 

and is important in the systematic planning, management, 

and evaluation of roadway research efforts across the 

Nation. FHWA also equips State and local agencies 

with the tools and knowledge to deliver significant 

safety improvements to the public. For example, implementing roundabouts and new designs at busy intersections 

have reduced fatal crashes, and improvements to existing 

roadway conditions have enhanced both pedestrian and 

bicyclist safety.

FHWA’s safety research also focuses on the causes of 

roadway fatalities and injuries by closely examining highway 

designs, road construction practices, and maintenance 
Federal Highway Administration 7

operations. These efforts have resulted in the development of strong data analysis tools that enable transportation professionals and researchers to connect 

crash causes with effective solutions. 

Research Activities

Research activities are connected directly to FHWA 

safety-related objectives. Each of the activities 

described below promotes safety improvement 

initiatives for motorists, pedestrians, and bicyclists. 

Improving Data and Tools for Safety Analyses

Collecting and analyzing data are major components 

of any safety improvement program. This is why 

one of FHWA’s strategic safety goals is to improve 

safety data and expand capabilities for analysis and 

evaluation.4

 FHWA is committed to making datadriven decisions that optimize investments in safety 

improvements to the Nation’s roads. As an example, 

FHWA leads an effort called Evaluations of Low 

Cost Safety Improvements Pooled-Fund Study 

(ELCSI-PFS), which involves 38 State DOTs and 

impacts the direction of safety research and its application nationwide. The goal of the ELCSI-PFS research 

is to create reliable estimates of the effectiveness of 

low-cost safety improvements identified as strategies 

in the National Cooperative Highway Research Program 

(NCHRP) Report 500 Guidebooks. The ELCSI-PFS 

estimates are determined through scientifically 

rigorous before-and-after evaluations at locations 

in the U.S. where these strategies are field tested. 

One example of an ELCSI-PFS study conducted in 

2014 was titled, Safety Evaluation of Centerline plus 

Shoulder Rumble Strips. The intent of the rumble 

strip countermeasure is to reduce the frequency 

of crashes by alerting drivers when they are about 

to leave their travel lane. Data were collected on 

two-lane rural road locations using rumble strips in 

Kentucky, Missouri, and Pennsylvania. The results 

showed a 23 percent decrease in fatalities and injuries 

combined. An economic analysis revealed that the 

combination of shoulder and centerline rumble strips 

is a very cost-effective treatment with benefit-cost 

ratios ranging from 11:1 to 30:1. 

FHWA has also developed a number of innovative 

tools to collect and evaluate roadway and vehicle data 

in order to identify and address critical safety issues 

and hazards. One example is the Interactive Highway 

Safety Design Model (IHSDM), which is a suite of 

six software modules used to evaluate the safety and 

operational effects of geometric design decisions.5

The IHSDM includes the Crash Prediction Module, 

which estimates the number of crashes that can 

be expected on a current or proposed design of a 

particular highway segment. The crash estimate helps 

designers and planners identify the combination of 

design details—such as curvature, grade, cross slope, 

and intersection location and design—that 

will minimize future crashes at a specific location. 

Another module, the Policy Review Module, checks 

the current or proposed roadway design details on 

a given road segment, to see how well that design 

matches current design policies in that locale. The 

Crash Prediction Module is valid for rural two-lane 

roads, rural multilane roads, urban/suburban arterials, 

FHWA’s field research vehicle can study drivers’ eye movements in 

real world settings, collecting valuable data on driver distractions. 

(Image source: FHWA) 
8 The FHWA 2015 R&T Story: Research and Innovative Solutions for the Nation’s Highway Challenges

freeway segments, and ramps and interchanges. At 

present, the other five modules pertain only to rural 

two-lane roads. 

The Nevada DOT performed an analysis on a 

section of Nevada State Route (SR) 147 in Clark 

County over a 20-year period (2013-33). SR 147 is 

a low-volume, rural, two-lane highway with an 

abnormally high number of fatal and injury crashes 

over the last several years. Expected crash totals 

were estimated using the IHSDM to evaluate and 

prioritize safety improvement alternatives. Each 

alternative and the existing road conditions were 

entered into the IHSDM to predict the crashes for 

the next 20 years based on the geometry, projected 

traffic volumes, and the crash history along the 

corridor. The alternatives were evaluated independent of each other to see their impact and safety 

benefit on the corridor. Projected reductions in 

crashes for 2013-33 ranged from 1 percent for 

superelevation improvements, which pertain to 

banking adjustments along a horizontal curve, to 

21 percent for shoulder widening.

Improving the Safety of Pedestrians 

and Bicyclists 

A vital aspect of FHWA’s R&T activities is to 

collaborate with State and local agencies, and Tribal 

Lands, to identify safety challenges facing pedestrians 

and bicyclists; to develop tools, technologies, and 

countermeasures, which can address those problems; 

and to support our partners in applying those research results to their specific needs. A good example 

of that collaboration is the Haxton Way Pedestrian 

Pathway Project.

Located in Whatcom County in Bellingham, Washington, Haxton Way is a narrow, two-lane road with 

a fog line and only a few inches of paved shoulder. 

A fog line is the white line painted on the right 

side of the road that is used by drivers to maintain a 

vehicle in the center of the lane in areas of heavy fog. 

Pedestrians and bicyclists use the roadway to access 

essential community amenities. Over the years, 

a number of pedestrians and bicyclists have been 

struck and killed while traveling along this roadway. 

To improve safety, the Lummi Nation Planning 

Department in partnership with Whatcom County, 

Washington State DOT, the Bureau of Indian 

Affairs, and FHWA administered the project to 

construct an elevated, 8-foot-wide multiuse path 

on wetlands next to Haxton Way. Low-voltage, 

solar-powered LED lamps were installed along the 

new trail to provide low-intensity, environmentally 

friendly, and cost-efficient lighting. Each lamp, 

equipped with motion, light, and proximity sensors, 

is set to provide 25 percent brightness after sunset, 

but the brightness increases to 100 percent as walkers 

or cyclists approach each lamppost. Choosing an 

environmentally friendly lighting solution in a sensitive 

ecosystem reduced the mitigation impacts that are 

normally associated with conventional lighting. 

On this stretch of roadway, zero injuries, deaths, or 

crashes have been reported since project completion. 

Local citizens and Tribe members now feel safe 

walking or biking along the amply lit pathway, well 

U.S. Interstates carry 25 percent of the Nation’s traffic, making 

highway safety a primary concern for FHWA. (Image source: FHWA)
Federal Highway Administration 9

away from oncoming cars and the congested roadway. 

Construction of the Haxton Way Pedestrian Path 

was funded by FHWA, which also provided overall 

project stewardship, oversight, and technical assistance 

throughout the project development process. 

Analyzing and Testing Roadside Safety and 

Security Barriers 

Keeping travelers safely on the roadway is a top 

priority for FHWA, where the focus is on developing roadside safety features that guide travelers’ 

vehicles back on the roadway when they stray, and 

that minimize the consequences to travelers when 

their vehicles depart the roadway. To do this, FHWA 

uses cutting-edge computer simulations, including 

advanced finite element modeling and full-scale crash 

tests to examine the effectiveness of features such as 

roadside safety barriers and security barriers.

FHWA-sponsored research proves that the 

effectiveness of cable median barriers can be affected 

by the position of the barrier within the median 

cross section. Cable median barrier research was 

prompted by cross-median crashes in which vehicles 

slid under generic three-cable, low-tension barriers 

placed along the centerline of V-shaped medians 

with sloped sides. Part of the problem was attributed 

to vehicle dynamics resulting from suspension system 

compression and vehicle rebound once the car left 

the road surface and crossed the slope. A total of 

72 terrain tests were conducted at FHWA’s Federal 

FHWA created an environmentally sensitive, multiuse path beside the Haxton Way in Washington that eliminated fatalities on roadway shared 

by pedestrians, bicyclists, and motorists. (Image source: FHWA)
10 The FHWA 2015 R&T Story: Research and Innovative Solutions for the Nation’s Highway Challenges

Outdoor Impact Laboratory (FOIL), involving different vehicles at various speeds traveling through 

different V-shaped medians. These tests were conducted to gather validation data for all the vehicle 

dynamic simulations needed for these cable barrier 

studies. This research showed that even a 3-foot difference in lateral placement of the 

barrier improved how the vehicle made contact with 

the barrier, leading to fewer vehicle underrides. 

Keeping employees safe and protecting vital government facilities from terrorist threats at home and 

abroad is essential for sustaining employee confidence and maintaining workforce efficiency. 

Security barriers are used to harden the perimeter 

of Government buildings and critical facilities, 

preventing the unwanted intrusion of speeding 

motor vehicles. FHWA works closely with the 

Department of State (DOS) to keep vehicular 

bomb threats as far as possible from diplomatic and 

government buildings by researching, testing, and 

constructing perimeter anti-ram fences and barriers. FHWA is collaborating with the DOS to create 

cutting-edge computer models and crash simulations 

that closely examine the effectiveness of security 

barriers. Full-scale crashes are conducted at FOIL 

to test and improve the design, application, 

construction, and deployment of infrastructure 

security barriers. 

Looking Ahead Toward Driver Behavior Analysis 

and New Connected Vehicle Technology

Looking ahead, Safety R&D will continue to 

develop, refine, and deploy advanced data capture 

and analysis tools to improve safety decisionmaking 

and save lives. TFHRC is establishing a new Safety 

Training and Analysis Center that will be a source 

for training and technical support for State DOTs 

and research partners who want to use the safetydata sets from the Second Strategic 

FHWA’s Federal Outdoor Impact Laboratory tests safety barriers like the one above to improve their design and construction. 

(Image source: FHWA)
Federal Highway Administration 11

Highway Research Program (SHRP2) Naturalistic 

Driving Study to gain insights into driver behavior.

Analysis of the SHRP2 safety data will help 

researchers understand how drivers react to their 

entire environment, inside and outside the vehicle, 

which will help to improve roads, vehicles, driver 

training, and enforcement measures thus reducing 

the number of crashes and resulting injuries.

Through the Exploratory Advanced Research 

Program (EAR), FHWA is also funding the 

development of other software tools to automate the 

extraction of information from massive video datasets 

so that the widest possible range of researchers will 

be able to use SHRP2 safety data.

Safety R&D is leading research into how new 

automotive technologies like connected vehicles 

and automated vehicles can be harnessed to prevent 

crashes. These technologies aim to enable safer 

vehicles and roadways by developing better crash 

avoidance, performance measures, and infrastructurebased cooperative safety systems to facilitate the 

communications among vehicles and the roadside. 

Safety R&D is actively engaged in how these technologies can help people avoid crashes, through new 

safety advisories, warnings, and messages to augment 

the driver’s situational awareness.

FHWA is contributing to several aspects of the 

Connected Vehicle Program. For example, the 

Human Factors Laboratory, at TFHRC, is using 

its state-of-the-art driving simulator to collect data 

and evaluate how drivers’ abilities and limitations 

may influence Cooperative Adaptive Cruise Control 

(CACC) system performance and design. 

The next generation of vehicle technology, coupled 

with the advances in safety research that have been 

realized to date, will enable USDOT to achieve its 

vision of Toward Zero Deaths.

Improving Safety for Motorists, Pedestrians, 

and Bicyclists 

The research being conducted by FHWA supports 

the USDOT’s and FHWA’s safety commitment by 

applying focused, collaborative, and strategic 

research methods that result in innovations and new 

technologies. FHWA promotes a safety culture that 

relies on scientific methods and data-driven decisionmaking for transportation-related programs and 

projects. FHWA’s efforts are leading to reductions in 

traffic crashes, fatalities, and injuries on our Nation’s 

roads and highways, and the Agency will continue to 

encourage and promote this science-based research 

now and into the future. 

For More Information

The following Web sites are provided for additional information, and 

further highlight the transportation challenges and FHWA activities 

discussed above. 

Lummi Nation Haxton Way Pedestrian Pathway Project: 

https://www.fhwa.dot.gov/planning/processes/tribal/case_studies/

lummi.pdf. 

Haxton Way YouTube Video: https://www.youtube.com/

watch?v=ltR2oiQ3R9Q. 

3. National Highway Traffic Safety Administration, Traffic Safety Fact 2012, 

Washington, DC. Accessed online: July 30, 2014. 

(http://www-nrd.nhtsa.dot.gov/Pubs/812032.pdf)

 4. Federal Highway Administration (2014). ”Roadway Safety Data Program.” 

(Web page) Washington, DC. Accessed online: July 30, 2014. 

(http://safety.fhwa.dot.gov/rsdp/about.aspx)

 5. Federal Highway Administration (2014). “Interactive Highway 

Safety Design Model (IHSDM): Overview.” (Web page) Washington, DC. 

Accessed online: July 30, 2014.

 (http://www.fhwa.dot.gov/research/tfhrc/projects/safety/comprehensive/ihsdm/)

 
12 The FHWA 2015 R&T Story: Research and Innovative Solutions for the Nation’s Highway Challenges

Examples of FHWA research 

and innovation delivery 

activities:

• Streamlining Traffic Flow with Adaptive 

Signal Control Technology

• Reducing Congestion with Cooperative

Adaptive Cruise Control

• Improving Mobility and Safety with

Automated Vehicles

Above: Vehicle-to-infrastructure technology for 

connected vehicles can help motorists safely navigate 

busy intersections. Below: Cameras on traffic signals 

linked to connected vehicles can alert drivers to 

pedestrians or bicyclists in a crosswalk, improving 

safety and mobility for all. (Images: FHWA)

Improving 

the Mobility 

of People 

and Goods

A growing economy needs highways that 

safely and reliably move people and goods 

where they need to go.

Traffic congestion on urban roads and highways has become 

increasingly problematic. Roughly 40 percent of average 

travel delays now occur outside normal rush-hour periods.6

 

Traffic conditions are becoming less consistent from day to 

day, forcing commuters to factor even more “buffer time” 

into their trips to ensure on-time arrival, according to an 

annual nationwide study by the Texas A&M Transportation 

Institute.7

 In 2010, congestion and delay on the Nation’s 

highways accounted for more than $100 billion in lost time 

and wasted fuel, and in 2012, the average commuter wasted 

38 hours in traffic and spent an extra $818 in fuel costs 

due to congestion. These congestion delays increase driver 

dissatisfaction and adversely impact the ability of businesses 

to deliver goods and services.

Agencies have a limited ability to add new roads to relieve 

growing congestion; therefore, they must look to new 
Federal Highway Administration 13

technologies that help maximize the capacity of 

existing roadway infrastructure and make transportation more reliable. A reliable highway system helps 

set commuter expectations of travel times so that 

they can plan their trips more effectively. Reliability 

also ensures the just-in-time delivery of goods that 

drives the Nation’s retail and manufacturing economy. Improved system operations and reliability better 

enables people to access jobs, deliver key services and 

products, reach needed amenities, and contribute to 

the national economy. 

Through operations research, development, and 

testing, FHWA is advancing new technologies and 

innovative processes to increase highway capacity, 

reduce traffic congestion and unreliability, and improve 

traffic analysis techniques. FHWA sponsors research 

on automated and connected vehicle applications 

that could potentially double the practical capacity 

of dedicated freeway lanes8

 and save fuel. FHWA’s 

research includes simulation studies of the benefits 

of these applications, and efforts are underway to 

develop prototype applications for field testing.

Research and traffic management best practices give 

State and local agencies the tools to solve operational challenges. Improved, real-time management 

of disruptions, such as adverse weather and crashes, 

enables transportation agencies to maintain a reliable 

highway system even when traffic volume is high or 

when incidents occur. FHWA helps agencies employ 

innovative tools to assist with real-time management, 

including traffic and weather sensors, wirelessly 

connected vehicles, remote management of traffic signals, automated vehicles, and adaptive cruise 

control. At the forefront of bringing these innovative 

technologies into the mainstream, FHWA is helping transportation agencies incorporate 21st century 

tools and policies in their own practices. 

Research Activities

The activities described in this section are examples 

of research, tools, and innovative technologies that 

FHWA is supporting to improve mobility and 

sustain the Nation’s highway system. One of FHWA’s 

primary objectives is to manage congestion by 

improving highway reliability and operating the 

system at peak performance. 

Streamlining Traffic Flow with Adaptive Signal 

Control Technology

The goal of traffic signal timing is to maintain the 

safe and efficient flow of vehicles at intersections. 

Poor traffic signal timing accounts for more than 

10 percent of all traffic delay and congestion on 

major routes. Conventional signal control systems 

rely on preprogrammed, daily signal timing schedules, which require an extensive amount of traffic 

data that must be collected manually. Conventional 

signal control systems also do not accommodate 

variable and unpredictable traffic demands, such as 

special events. Older signal timing systems cause 

substantial losses for businesses and consumers due 

to decreased productivity and increased labor costs. 

Adaptive signal control technology (ASCT) adjusts 

the timing of red, yellow, and green lights to accommodate changing traffic patterns. ASCT uses realtime traffic information to reduce congestion by 

determining which lights should be red and which 

should be green. The main benefits of ASCT are that it:

• Equitably distributes green light timing for all 

traffic movements. 

• Improves travel time reliability by progressively 

moving vehicles through green lights. 

• Prolongs the effectiveness of traffic signals and 

their associated timing. 

• Reduces emissions due to improved traffic flow.

On average, ASCT improves travel time by more 

than 10 percent. In areas with particularly outdated 

signal timing, improvements can be greater than 50 

percent. Starting in the early 1990s, FHWA developed and demonstrated four ASCT approaches for 
14 The FHWA 2015 R&T Story: Research and Innovative Solutions for the Nation’s Highway Challenges

dynamically updating signal timing. Following 

the positive results of this foundational research, 

FHWA initiated an effort to expand the deployment 

of ASCT systems across the Nation. This deployment effort has contributed to a 192 percent increase 

in implementation from 2009-2014, with multiple 

ASCT products now available in the marketplace.9

Reducing Congestion with Cooperative 

Adaptive Cruise Control

FHWA researchers envision that drivers will share 

vehicle control with an automated system that 

includes pervasive vehicle-to-vehicle (V2V) and 

infrastructure-to-vehicle (V2I) connectivity via 

Dedicated Short-Range Communications (DSRC). 

DSRC are one- or two-way short- to medium-range 

wireless communications designed specifically for use 

in vehicles. Cooperative Adaptive Cruise Control 

(CACC) allows vehicles to use DSRC to broadcast 

their speed, following distance, and acceleration and 

deceleration rates to other CACC-equipped vehicles. 

Vehicles equipped with CACC use this information 

to automatically apply the brakes as needed to maintain a safe distance from the vehicles ahead, allowing 

for closer following distances and for more vehicles 

to safely use the existing roadway. FHWA is conducting research to identify and analyze early CACC 

concepts and assess the range of possible benefits, 

which the agency anticipates will include increased 

vehicle efficiency and reduced fuel use. FHWA is 

also funding research on CACC specifically for 

trucks, called “truck platooning.”

Connected vehicles can also use DSRC to broadcast 

performance data to roadway infrastructure to track 

traffic flow and crashes or incidents. FHWA will use 

the performance data to develop predictive traffic 

models for more effective traffic management. 

Improving Mobility and Safety with Automated 

Vehicles 

Automated vehicle technology has the potential 

to streamline mobility, lower the number of traffic 

crashes, decrease congestion, and reduce the high 

costs associated with lost time and wasted fuel. The 

technology also could create safer and more efficient 

travel for those with mobility issues. 

Automated vehicles are precisely controlled, using 

advanced wireless communications, onboard computers, 

advanced vehicle sensors, and Global Positioning 

System (GPS) navigation. FHWA has identified 

opportunities where automation can significantly 

enhance the operation of the highway transportation 

system. Research sponsored by FHWA suggests that 

significant public benefits in terms of mobility, fuel 

use, emissions, and safety can be achieved through 

the introduction of some partially automated systems where drivers maintain control of the steering 

function while automated systems control the vehicle 

speed. Several States are testing automated vehicle 

technologies that could lead to future innovations. 

Creating a Safer, More Reliable 

Transportation System

As more drivers put pressure on the transportation 

system, FHWA is identifying solutions to make 

roadways safer and travel times more reliable for 

everyone. Streamlining the movement of vehicles 

is about more than improving driver experience; it 

affects the Nation’s ability to remain economically 

competitive. FHWA works diligently to provide 

tools and promote innovations that will solve 

the challenges of traffic congestion and delay. 

Ensuring that people are able to travel reliably and 

that goods and services are delivered efficiently is 

paramount. To be successful in this area, FHWA is 

looking at 21st-century technologies and tools that 

will bridge the gap between old and new traffic 

management strategies. 
Federal Highway Administration 15

For More Information

The following Web sites are provided for additional information, and 

further highlight the transportation challenges and FHWA activities 

discussed above. 

Exploratory Advanced Research (EAR) Program Fact Sheet - 

Beyond Traffic Signals: A Paradigm Shift: http://www.fhwa.dot.gov/

advancedresearch/pubs/10023/10023.pdf. 

Cooperative Adaptive Cruise Control: Applications Development and 

Research: http://www.its.berkeley.edu/publications/UCB/2011/PRR/

UCB-ITS-PRR-2011-9.pdf. 

Cooperative Adaptive Cruise Control: Human Factors Analysis:

http://www.fhwa.dot.gov/publications/research/safety/13045/index.cfm. 

Adaptive Signal Control: http://www.fhwa.dot.gov/everydaycounts/

technology/adsc/. 

FHWA R&T Research Technology Agenda: http://www.fhwa.dot.gov/

research/fhwaresearch/agenda/index.cfm. 

6. Jones, S (2013). Cooperative Adaptive Cruise Control: Human Factors 

Analysis. Federal Highway Administration, Washington, DC. 

7. Texas A&M Transportation Institute (2012). 2012 Annual Urban Mobility 

Report. College Station, Texas. Accessed online: July 30, 2014. 

(http://mobility.tamu.edu/ums/)

8. Kuehn, David and Fitzgerald, Mark. (November/December 2013).

“Breakthroughs to the Future.” Public Roads.

http://www.fhwa.dot.gov/publications/publicroads/13novdec2013/01.cfm

9. Federal Highway Administration (2014). Unpublished, raw data. For additional 

information, contact the FHWA Resource Center and Office of Operations: 

http://ops.fhwa.dot.gov/arterial_mgmt/index.htm. Washington, DC.

FHWA research in arterial management seeks to improve traffic flows in congested intersections. (Source: FHWA Adaptive Signal 

Control Program) 
16 The FHWA 2015 R&T Story: Research and Innovative Solutions for the Nation’s Highway Challenges

Top: Trucks deliver concrete for the deck of the 

existing Paseo Bridge in Missouri as part of a project 

that used innovative design techniques to 

accelerate bridge construction. Above: FHWA and 

Oregon DOT use accelerated bridge construction to 

rapidly remove and replace five bridges on Oregon 38. 

Rapid bridge replacement technology used hydraulic 

jacks mounted on a sliding rail to slide the old superstructure onto temporary supports and move the new 

superstructures into their final position. (Images: FHWA)

Examples of FHWA 

research and innovation 

delivery activities:

• Accelerating Infrastructure Construction 

and Assessment

• Accelerating Bridge Construction to 

Reduce Congestion

• Improved Bridge Deck Condition 

Assessments via the RABITTM Bridge 

Deck Assessment Tool

• Producing Low-Cost, Long-Lasting 

Rockery Retaining Walls

• Developing Rapid Post-Disaster 

Recovery Assessment

Preserving 

the Nation’s 

Infrastructure

To keep pavement, bridges, and other types 

of infrastructure in a state of good repair, 

FHWA fosters innovations that increase 

longevity while enabling improved monitoring 

of road conditions.

As the Nation’s transportation infrastructure ages, 

maintaining the highway system in a state of good repair 

will become significantly more complicated and expensive. 

According to FHWA in 2012, more than 66,000 bridges 

in the U.S. were rated as structurally deficient. Structural 

deficiencies are characterized by deteriorated conditions 

of significant bridge elements and potentially reduced 

load-carrying capacity.10

The investment required to rebuild these bridges is 

estimated to be more than $51 billion.11 FHWA’s research 

is forward-looking, and supports advancement of innovative 

materials and designs, improved infrastructure management 

and preservation practices, better construction techniques, 

and improved quality control to advance infrastructure 

safety, longevity, and environmental sustainability. 
Federal Highway Administration 17

Research Activities

FHWA is pursuing a variety of research to address 

highway infrastructure challenges. For example, 

FHWA is researching new methods and processes to 

accelerate infrastructure construction, such as precast 

concrete deck panels in bridge construction. Efforts 

to help highway agencies effectively assess and 

manage infrastructure include pursuit of innovative 

tools to evaluate bridge deck conditions, and posthazard assessment guidelines for flooded roadways. 

The research activities below illustrate FHWA’s 

important role in each of these areas with specific 

examples of innovative solutions. 

Accelerating Infrastructure Construction 

and Assessment

Roughly 10 percent of the Nation’s 600,000 bridges 

require major rehabilitation, repair, or complete 

replacement.12 The work that occurs on the construction site can significantly impact mobility and safety. 

In some cases, the direct and indirect costs of traffic 

detours or road closures as a result of bridge construction far exceed the cost of the structure itself.13 

FHWA has initiated a number of projects to speed up 

or accelerate infrastructure construction and preserve 

existing infrastructure. FHWA research has led to 

the Accelerated Bridge Construction (ABC) processes, which include innovative planning, design, 

materials, and composite construction methods, in a 

cost-effective manner to build or replace bridges. As 

part of the deployment initiative, Every Day Counts, 

most States are using one or more ABC techniques. 

ABC can lead to reduced agency costs, improved 

motorist and worker safety, improved mobility around 

bridge construction projects, better initial quality if 

using prefab components, and more durable and lasting bridges. ABC technologies include the following: 

• Prefabricated bridge elements and systems (bridge 

components built offsite, or adjacent to the 

Construction of the roadway surface nears completion on the Christopher Bond Bridge construction project in Kansas City, Missouri. The 

innovative side-by-side bridge constructive technique saved time and minimized road closures. (Image source: FHWA)
18 The FHWA 2015 R&T Story: Research and Innovative Solutions for the Nation’s Highway Challenges

alignment, reducing onsite construction time 

and mobility).

• Geosynthetic reinforced soil-integrated bridge system 

(use of alternating layers of compacted granular 

fill encapsulated by geotextile fabric sheets to 

build support for the bridge.)

• Slide-in bridge construction (new bridge built on 

temporary supports parallel to an existing bridge 

and upon completion the old bridge is demolished 

and a new bridge is slid into place, tied into the 

approaches, and paved within 48 to 72 hours).

The impact of using these innovations can be seen in 

the following examples: 

• Nevada used slide-in bridge construction and shut 

down a road for only 56 hours to replace a bridge, 

saving an estimated $12.7 million in time and fuel 

costs for commuters. 

• Sandy Township in Clearfield County, Pennsylvania replaced a bridge using the geosynthetic 

reinforced soil-integrated bridge system with its 

own equipment and workforce in only 35 days, 

saving months of detours and delays.

Accelerating Bridge Construction to 

Reduce Congestion

Conventional bridge deck construction follows an 

onsite sequential process: building the substructure, 

construction and placement of either steel or 

concrete superstructure girders, followed by concrete 

bridge deck curing. These activities can impede traffic flow, causing travel delays for the motoring public 

and reducing safety for drivers, pedestrians, and 

construction personnel. ABC strategies have gained 

traction because they shorten project delivery, 

enhance roadway safety, and protect the environment. 

Prefabricated, full-depth concrete deck panels are 

increasingly used in ABC processes in which 

modular components of a deck are precast off-site 

and then joined together at the bridge construction 

site. Modular precast concrete deck panels improve 

the safety and efficiency of the bridge construction 

process. Roadwork can be completed overnight, on 

weekends, and during off-peak hours, reducing congestion, road closures, and work zones. Since October 2010, more than 2,496 replacement bridges have 

been designed or constructed using prefabricated 

bridge elements and systems. Successful applications 

of full-depth precast concrete deck panels include the 

US-24 Mississippi River Bridge in Illinois and the 

24th Street Council Bluffs in Iowa.

Precast concrete deck panels are placed on top of 

concrete or steel bridge girders and a composite connection is formed with the girders. For panels placed 

on steel girders, they are connected using shear studs 

that were previously welded to the girders. Deck 

panels have pockets that fit around the shear studs 

and are then filled with grout or concrete to form a 

composite bond with the steel girder.14 For precast 

deck construction, it is advantageous to cluster the 

Placing of rebar prior to concrete pour during construction of a 

pylon on Christopher Bond Bridge construction project was one of 

many cost-effective, technical engineering solutions that saved time 

and provided flexibility in the bridge construction schedule. (Image 

source: FHWA)
Federal Highway Administration 19

studs closer together and increase the distance 

between the clusters, which simplifies panel 

fabrication and constructability.

FHWA is conducting full-scale static and fatigue 

tests of composite beams constructed with steel 

beams and precast concrete deck panels, seeking 

to increase the space between clusters to make 

conditions more favorable to precast concrete deck 

panel construction. 

Improved Concrete Bridge Deck Condition 

Assessments via the RABITTM Bridge Deck 

Assessment Tool

One way to reduce the number and cost of bridge 

rehabilitation projects is to identify the anticipated 

future condition concerns of a bridge deck. FHWA’s 

Long-Term Bridge Performance program developed 

a multifunctional research tool to better characterize 

the condition of bridge decks. The RABITTM bridge 

deck assessment tool, invented jointly by FHWA and 

university researchers, deploys a suite of technologies 

to help FHWA researchers collect comprehensive 

data on bridge deck surface and subsurface 

conditions automatically and simultaneously.

The combination of surface/subsurface tools allows 

bridge engineers to quickly identify bridge deck areas 

of concern—corrosion, cracks, and other forms of 

infrastructure deterioration. Data collected by the 

RABITTM bridge deck assessment tool are tagged 

with GPS coordinates for accurate location reference. Maintenance crews can use those coordinates 

to locate, inspect, and repair any damaged areas of 

the bridge deck surface or subsurface. The RABITTM 

bridge deck assessment tool can collect data from 

approximately 4,000 square feet of bridge deck per 

hour using a combination of onboard nondestructive tools and image processing capabilities, which 

require a minimum of two people to safely operate. 

The same assessment using conventional handheld 

equipment and individual operators would require 

a minimum crew of five people to collect data at 

the same resolution as the RABITTM bridge deck 

assessment tool. The conventional method is 

performed at a lower rate of approximately 500 

square feet per hour, which would take eight times 

as long to collect the same amount of data. The 

RABITTM bridge deck assessment tool also automatically collects, reduces, stores, and provides a visual 

representation of all data collected in near real time. 

In addition, the RABITTM bridge deck assessment 

tool minimizes both traffic interruption and exposure 

of field personnel to hazardous conditions. 

Producing Low-Cost, Long-Lasting Rockery 

Retaining Walls 

In November 2006, FHWA developed innovative 

guidelines to build cost-effective and structurally sound 

rockeries. Rockeries, or dry stack walls, are rough, 

natural, onsite rock structures that are stacked and 

interlocked with no mortar, concrete, or steel. They offer 

a low-cost, long-lasting, safe, and visually appealing way 

to retain and protect earth-cut or fill slopes. 

Prior to 2006, no standards, specifications, or other 

accepted procedures existed to provide construction or 

The RABITTM bridge deck assessment tool is eight times faster 

than conventional methods at collecting data on the conditions of 

a bridge’s deck and subsurface. (Image source: FHWA) 
20 The FHWA 2015 R&T Story: Research and Innovative Solutions for the Nation’s Highway Challenges

design guidance for rockeries; however, rockeries 

functioned well in many different types of environments, suggesting that excellent performance could 

be expected when certain conditions were met. A 

rational, tested design procedure was needed to provide 

designers and federal landowners with confidence that 

rockery structures could be used as part of modern 

highway engineering.

FHWA produced design and construction guidelines to 

define and evaluate the stability of rockeries given specific geometries (height, base width, and batter); rock 

properties and placements; and backfill materials. The 

guidelines also include construction quality assurance 

steps, standard plan drawings, and construction specifications. Rockeries help meet sustainability goals by 

using onsite materials, and at the same time they deliver 

unique context-sensitive solutions. To date, more than 

80 rockeries have been built following the guidelines, 

resulting in a cost of $20 to $30 per square foot, compared with $70 to $100 per square foot for conventional 

walls.15 A recent example from Fishlake National Forest 

in central Utah (constructed at $20 per square foot) is 

shown in the photo at the top of the page.

Developing Rapid Post-Disaster Recovery 

Assessment

Floods can cause serious damage to roadways, often 

undermining the integrity of asphalt, concrete, and 

gravel roads. After a flood, highway agencies must 

quickly assess the extent of damage and perform 

repairs necessary to safely reopen the highway and 

maintain traffic flow. FHWA is currently conducting research to develop guidelines that transportation agencies can use to evaluate flood impacts on 

pavements and how quickly damaged roads can be 

reopened to emergency vehicles. In pursuing this 

research, FWHA is drawing on the experiences of 

State agencies responsible for infrastructure impacted 

by flooding.

Preserving the Nation’s Infrastructure

U.S. bridges and highways make up one of the most 

complex and wide-ranging transportation systems 

in the world. Maintaining safe infrastructure and 

its integrity is a priority for FHWA. Infrastructure 

investments spur economic growth, create well-paying 

jobs, and enable citizens to reach necessary amenities 

FHWA guidelines on building rockeries, like this one on State Route 153 in Utah’s Fishlake National Forest, have reduced the cost of building 

walls by as much as 50 percent. (Image source: FHWA)
Federal Highway Administration 21

more reliably and efficiently. FHWA is advancing 

new construction techniques, assessment tools, 

technologies, and more sustainable building materials 

to construct longer-lasting bridges and highways in 

less time with reduced costs. 

For More Information

The following Web sites are provided for additional information, and 

further highlight the transportation challenges and FHWA activities 

discussed above. 

Every Day Counts 2012 Initiatives: Accelerated Bridge Construction: 

http://www.fhwa.dot.gov/everydaycounts/edctwo/2012/abc.cfm. 

Accelerated Bridge Construction Fact Sheet: http://www.ops.fhwa.

dot.gov/WZ/practices/factsheets/factsheet16/index.htm. 

RABITTM Bridge Deck Assessment Tool Overview: http://www.fhwa.

dot.gov/research/tfhrc/programs/infrastructure/structures/ltbp/ltbpresearch/rabit/index.cfm.

Final Report – Rockery Design and Construction Guidelines: 

http://www.cflhd.gov/programs/techDevelopment/geotech/rockeries/

documents/01_Rockery_Entire_Document.pdf. 

10. Federal Highway Administration (2013). “Estimated 2012 Costs 

to Replace or Rehabilitate Structurally Deficient Bridges.” (Web page) 

Washington, DC. Accessed online: September 26, 2014. 

(http://www.fhwa.dot.gov/bridge/nbi/sd2012.cfm)

11. Federal Highway Administration (2013). “Estimated 2012 Costs 

to Replace or Rehabilitate Structurally Deficient Bridges.” 

(Web page) Washington, DC. Accessed online: September 26, 2014. 

(http://www.fhwa.dot.gov/bridge/nbi/sd2012.cfm)

12. Federal Highway Administration (2013). “Estimated 2012 Costs 

to Replace or Rehabilitate Structurally Deficient Bridges.” 

(Web page) Washington, DC. Accessed online: September 26, 2014. 

(http://www.fhwa.dot.gov/bridge/nbi/sd2012.cfm)

13. Federal Highway Administration (2013). “Accelerated Bridge Construction.” (Web page) Washington, DC. Accessed online: February 18, 2015. 

(http://www.fhwa.dot.gov/bridge/abc/) 

14. Ocel, J. and Provines, J. (2014). “Strength and Fatigue Resistance of 

Clustered Shear Studs.” Proceedings of the 2014 World Steel Bridge 

Symposium. March 26-29, 2014, Toronto, Ontario.

15. Federal Highway Administration (2015). “Research and Technology 

Agenda. Meeting the Challenge: Federal Lands.” (Web page) 

Washington, DC. Accessed online: February 18, 2015. 

(http://www.fhwa.dot.gov/research/fhwaresearch/agenda/researchareas.

cfm?urlanchor=federalLands#newhd3)
22 The FHWA 2015 R&T Story: Research and Innovative Solutions for the Nation’s Highway Challenges

Examples of FHWA research 

and innovation delivery 

activities:

• Developing Better Intersection Design

Saves Lives and Money: Diverging 

Diamond Interchanges 

• Improving the Freight Network for

Economic Growth and Commerce

• Fostering Better Transportation 

Decisions through Better Data

Above: A design drawing for a diverging diamond 

interchange shows how the novel design reduces 

turning conflicts in an intersection. Starting from the 

left, the yellow arrows show a vehicle’s progress 

through the intersection. The red arrows show how 

the vehicle would merge onto the freeway while the 

green arrow shows its progress across the overpass. 

Below: Workers finish construction on a new 

diverging diamond interchange. (Images: FHWA)

Enhancing 

System 

Performance

Promoting effective tools and research to help 

decrease highway congestion, safety risks, 

and wear and tear on roadways.

With limited space and budgets to build more lanes or 

roads, today’s transportation agencies are looking for 

innovative ways to get the most out of existing roadways. 

FHWA is providing the research and tools needed to 

effectively plan for increased traffic, measure and evaluate 

roadway performance, and identify desired outcomes that 

respond to congestion. Improving the performance of the 

highway system (particularly its safety, reliability, effectiveness, and sustainability) can reduce safety hazards, limit 

wear and tear on roadways and vehicles, and minimize 

driver frustration and delay. 

Research Activities

FHWA is enhancing system performance through diverse 

research projects. Examples include studying safer and more 

efficient ways to merge highway traffic, providing up-todate freight data that help lower shipping costs, and helping 

predict future travel demand and driver habits.
Federal Highway Administration 23

Developing Better Intersection Design 

Saves Lives and Money: Diverging Diamond 

Interchanges 

Highway intersections can cause congestion and are 

dangerous for through traffic and vehicles turning 

to access or exit a highway. To improve traffic flow 

and reduce incidents in these areas, FHWA transportation engineers designed diverging diamond 

interchanges (DDI). FHWA also commissioned a 

research study to evaluate DDI installations to better 

understand the operational efficiency and safety of 

the design, and tested the design in the human 

factors laboratory at TFHRC.

The DDI design (see illustration to the right) 

moves through traffic and left-turning vehicles to 

the left side of the road at highway intersections. 

This configuration reduces the number of potential 

conflict points in an intersection. Conflict points are 

the point at which a roadway user can cross, merge, 

or diverge with another roadway user. Reducing the 

number of conflict points will lead to safer intersections for motorists, pedestrians, and bicyclists. 

The first DDI in the U.S. was completed in June 

2009 at I-44 and MO 13 in Springfield, Missouri. 

Historically, this interchange had mile-long traffic backups and serious left-turn crashes. When the 

DDI was completed it eliminated rush hour congestion, proving the validity and effectiveness of the 

design. Installing a DDI costs roughly 60 percent less 

than conventional designs and can be completed in 

6 months, rather than the typical 18-month period 

using traditional construction techniques.16 Based 

on the proven success of the Springfield DDI, more 

than 30 DDIs interchanges have been built since 

2009. The State of New York saved $4.9 million and 

reduced total construction time in half by using a 

DDI rather than the partial cloverleaf configuration 

alternative, Colorado and the city of Grand Junction 

doubled the capacity for left turns and saved 70 

percent in construction costs over other alternatives 

for the DDI at I-70 and U.S. 6/50.

FHWA continues to conduct research to evaluate the 

operational and safety impacts of DDIs, identifying 

strategies to improve safety and accommodate pedestrians and bicyclists who travel along the same roads 

and highways. 

Improving the Freight Network for Economic 

Growth and Commerce

The volume of freight on the Nation’s highways 

has grown dramatically while shipping methods 

and materials have also changed. Freight professionals need accurate, current, and comprehensive 

information to effectively plan for goods movement. 

States and localities need information to perform 

economic analyses about major trading partners 

and the volumes and sources of traffic coming to 

their jurisdictions.

Diverging diamond interchanges reduce pedestrian conflicts at busy 

intersections near freeway ramps. (Source: Missouri DOT)
24 The FHWA 2015 R&T Story: Research and Innovative Solutions for the Nation’s Highway Challenges

An important aspect of enhancing system performance is supporting efficient movement of freight. 

FHWA developed the Freight Analysis Framework 

(FAF), an inventory that integrates data from several 

sources to create a comprehensive picture of freight 

movement for all modes of transportation, within 

and between States and major metropolitan areas. 

FAF also provides a tool that tabulates shipping data 

by mode and commodity to help decisionmakers 

manage national freight policy. Now freight analysts 

and planners can use FAF to better understand 

complex freight movements. By combining FAF 

estimates with other data and models they can 

examine relationships and make cost-effective 

decisions that improve freight flows and safety; 

reduce environmental impacts; promote economic 

activity; and support better integration of freight into 

transportation system operations.

Fostering Better Transportation Decisions 

through Better Data 

FHWA is also enhancing system performance by 

promoting the efficient, systematic, and comprehensive collection and utilization of national transportation data to improve highway management and 

investment decisions. National transportation data 

provide a breadth of systematic and related information on transportation systems, including temporal, 

geospatial, behavioral, and socioeconomic aspects. 

While parameters such as vehicle miles traveled 

(VMT), fuel efficiency, fuel consumption, population, 

aging, immigration, and greenhouse gas emissions 

are interlinked, such critical relationships are often 

poorly understood. 

FHWA is conducting research to develop national 

specifications for multiple transportation datasets, 

Long-haul freight traffic in the U.S. is concentrated along major routes between population centers, ports, border crossings, and other major 

activity hubs. (Image source: FHWA)
Federal Highway Administration 25

including vehicle classification; roadway functional 

classification; highway performance and monitoring; traffic monitoring; and household travel surveys. 

These efforts are expected to increase the effectiveness of agencies’ data collection and analysis efforts 

resulting in better consistency among datasets and 

improved data compatibility among government 

agencies and the private sector.

Recent advancements in modeling, statistical analysis, and computing speed have enabled more detailed 

analysis of the interrelationships among these datasets. 

FHWA seeks to apply advancements to national 

transportation data to help answer questions about 

the extent of demand for travel and how and why 

people travel. A greater understanding of the relationships between various data and parameters can 

help the transportation community devise effective 

strategies, programs, and policies to anticipate and 

meet the public demand for transportation, and 

ensure a higher-performing system now and into the 

future. The research paper Exploring the Relationship 

between Travel Demand and Economic Growth 17 helps 

States understand the relationship between travel 

demand and economic growth, examining if shifts in 

automotive and freight travel to other transportation 

modes would have any impact on the economy. The 

research paper found that there is no basis in current 

literature to suggest that efforts to increase environmental sustainability in transportation over the short 

term would require or depend on reducing VMT. In 

addition, no strong evidence exists to argue that policies enacted by States or MPOs to reduce VMT will 

negatively impact economic growth. 

Making it Last Longer: Getting the Most Out of 

Existing Roadways

With constrained space and budgets, it is more challenging than ever for transportation agencies to gain 

funding and approval for projects to add capacity, or 

additional lane-miles, to existing highway systems. 

Therefore, transportation stakeholders need data 

and tools to maximize the performance of existing 

infrastructure by effectively planning for and reducing congestion to move more vehicles. Other stakeholders, such as freight professionals, also need tools 

to effectively plan for expanding travel demand on 

the Nation’s roadways. FHWA’s research activities 

help meet the challenge of enhancing system performance by providing standardized measurement 

and data-driven solutions to help the transportation 

community make important decisions about current 

operations and future system needs.

For More Information

The following Web sites are provided for additional information, and 

further highlight the transportation challenges and FHWA activities 

discussed above. 

Driving the DDI at American Fork Main Street YouTube Video: 

https://www.youtube.com/watch?v=LqE1Z77ccwQ. 

FHWA Freight Analysis Framework: http://www.ops.fhwa.dot.gov/

freight/freight_analysis/faf/index.htm. 

FHWA Office of Highway Policy Information: http://www.fhwa.dot.

gov/policyinformation/pubs/pubsandprods.cfm. 

Final Report – Exploring the Relationship between Travel Demand 

and Economic Growth: http://www.fhwa.dot.gov/policy/otps/pubs/

vmt_gdp/vmt_gdp.pdf. 

16. Bared, Joe and Saiko, Don. (November/December 2010). “The Double 

Crossover Diamond.” Public Roads. 

17. Federal Highway Administration (2012). Exploring the Relationship 

between Travel Demand and Economic Growth. Washington, DC. 

Accessed online: February 18, 2015. 

(http://www.fhwa.dot.gov/policy/otps/pubs/vmt_gdp/vmt_gdp.pdf)
26 The FHWA 2015 R&T Story: Research and Innovative Solutions for the Nation’s Highway Challenges

Examples of FHWA research 

and innovation delivery 

activities:

• Promoting Roadside Revegetation:

An Integrated Approach to Establishing 

Native Plants

• Using Renewable, Reusable, and

Recycled Materials to Achieve a More 

Durable Highway Infrastructure

• Developing Innovative Tools to Assess 

Environmental Impacts

• Integrating Sustainability into

Transportation Projects

Above: Workers use a high-pressure jet wash 

and truck-mounted vacuum to remove debris from 

existing pipes as part of preparations for the FHWAsupported culvert reconstruction project conducted 

by Montana DOT using trenchless technologies. Half 

of the corrugated steel pipe culverts would be lined 

(sliplined) with high-density polyethylene pipe and 

half would be lined with cured-in-place pipe. Below: 

FHWA supported a new construction project with 

Georgia DOT. A solar-powered trailer and traffic 

sensor were used as part of the system. 

(Images: FHWA)

Promoting 

Environmental 

Sustainability 

The benefits of environmentally friendly 

transportation networks extend beyond the 

highway system.

Surface transportation significantly impacts the environment. Motor vehicles are responsible for 23 percent of 

greenhouse gas emissions in the U.S.,18 and while essential 

to supporting mobility and economic growth, traditional 

highway designs sometimes disrupt critical wildlife habitats. 

Each year, deer-to-vehicle collisions alone lead to approximately 200 human deaths and $1.1 billion in property 

damage.19

FHWA is a leader in developing new technologies and improved practices that minimize negative impacts on people, 

the environment, and natural resources. FHWA provides 

tools, technical assistance, proven processes, and data so 

State and local agencies can perform effective environmental planning. FHWA also supports transportation agencies’ 

efforts to protect natural spaces and resources that are vital 

to the health of the Nation’s wildlife.
Federal Highway Administration 27

Research Activities

Examples of FHWA R&T that support the environment include finding effective ways to grow native 

plants following a highway construction project, 

establishing policy that supports the use of recycled 

materials in construction, and developing online 

tools to integrate environmental considerations into 

standard business practices.

Promoting Roadside Revegetation: An Integrated 

Approach to Establishing Native Plants

Today, most road projects involve modifications to 

existing roads rather than new construction. Execution of such projects in a safe and effective way while 

maintaining ecological health is a critical component 

of success. Modifying roads or updating them section 

by section also presents a tremendous opportunity to 

remedy the oversights of the past, mitigate environmental impacts, and improve the health of affected 

ecosystems. Making the environment an important 

consideration for transportation improvements 

requires standardized guidance and a framework for 

collaboration across and among stakeholders. 

FHWA streamlines federal land management and 

Tribal processes to improve timeliness and effectiveness of program and project delivery. Through its 

Coordinated Technology Implementation Program, 

FHWA worked with the U.S. Forest Service to 

develop a comprehensive roadside revegetation 

technical guide, which offers an integrated approach 

to facilitate the successful establishment of native 

plants along roadsides and other areas of disturbance 

associated with road modifications.

The guide introduces a comprehensive process of 

initiating, planning, implementing, and monitoring 

a roadside revegetation project with native plants. 

The partnership also resulted in a Web site, at http://

www.nativerevegetation.org/, which contains integrated and interlinked modules dedicated to explaining the art and science of roadside revegetation.

Currently, FHWA’s Western Federal Lands 

Highway Division uses native vegetation in all of 

its construction projects. Both the National Park 

Service and the U.S. Forest Service have vigorous 

revegetation programs in place. Glacier National 

Park operates its own nursery to grow native plants 

for revegetation of disturbed areas. In addition, 

Oregon, Washington, and California State DOTs 

use native plants in many of their highway construction projects. 

Vegetation Management: An Ecoregional Approach

is a recent example of FHWA’s commitment to costeffective sustainability. FHWA encourages State land 

managers to adopt an ecoregional approach to better 

manage roadside vegetation, and the guide provides 

practical advice to help them accomplish this. The 

examples and instructions found in the guide make 

clear that, by using native plants in highway projects, 

States can save fuel and other maintenance costs 

while reducing their environmental impact. State 

DOTs have received copies of the guidebook, and an 

e-book version will be available in 2015.

Using Renewable, Reusable, and Recycled 

Materials to Achieve a More Durable Highway 

Infrastructure

FHWA is advancing the effective use of renewable, 

reusable, and recycled materials to reduce the cost 

of transportation projects and ease the effects of 

transportation construction on the environment. For 

example, use of reclaimed asphalt pavement (RAP) 

in pavement mixtures has been turning what might 

otherwise be sent to a landfill as waste material into 

a resource for more than 30 years. However, currently 

available guidance has proven inadequate to ensure 

that pavements built with RAP will be durable. 

FHWA has built and is currently testing full-scale 

pavements that contain specific levels of RAP to 

assess its performance. When completed, this 

research will deliver guidance to help highway 

agencies and their contractors achieve durable 

pavements when using RAP.
28 The FHWA 2015 R&T Story: Research and Innovative Solutions for the Nation’s Highway Challenges

Building on the research findings from FHWA 

and the knowledge-sharing provided by FHWA’s 

Sustainable Pavement Technical Working Group, 

numerous States are currently using recycled 

construction materials to save on costs and free 

up funds for additional highway construction, 

maintenance, and repair. For example, using recycled 

materials is commonplace on New York State 

Department of Transportation (NYSDOT) projects. 

Recycled materials allowed directly in the NYSDOT standard specifications include RAP, recycled 

concrete aggregate, beverage container glass, blast 

furnace slag, and coal fly ash, among others. Other 

recycled materials are evaluated on a case-by-case 

basis. For instance, average RAP in asphalt mixes is 

estimated to be around 15 to 20 percent and recycled 

concrete is the predominant granular material used 

in the metro New York Area. Additionally, when 

concrete is removed from pavements and structures, 

any reinforcing is typically removed and recycled, and 

the concrete often becomes fill material somewhere 

else on the project to flatten slopes and is occasionally used as filter material. The Department’s sustainability program, GreenLITES, has also contributed 

to the increased use of recycled and reused materials 

and greatly contributes to NYSDOT’s supporting a 

sustainable society.

Developing Innovative Tools to Assess 

Environmental Impacts 

The National Environmental Policy Act of 1969 

(NEPA) requires both the assessment of environmental impacts of federal activities and the planning 

of any needed mitigation to lessen or eliminate damage 

from construction activities. As part of its commitment to NEPA, FHWA requires the examination 

and avoidance of potential impacts to the social and 

natural environment when considering approval 

of proposed transportation projects. FHWA also 

incorporates into this process a NEPA-mandated 

interdisciplinary approach in planning and decisionmaking for any action that adversely impacts the 

environment. Transportation agencies need tools that 

facilitate collaboration across transportation, regulatory, and special-interest organizations to plan and 

deliver projects as quickly and efficiently as possible.

As part of its objective to promote more informed 

transportation decisionmaking, FHWA developed 

an online tool called e-NEPA to help practitioners 

streamline the NEPA process. e-NEPA is a real-time 

electronic collaboration tool that allows State DOTs 

to share documents, track comments, schedule tasks 

with participating agencies, and perform concurrent 

reviews of their environmental impact statements 

and environmental assessments. Currently, States 

are piloting the tool on a number of environmental 

impact statement and environmental assessment 

projects to determine impacts and success factors. 

Integrating Sustainability into 

Transportation Projects 

As environmental impacts play an increasingly 

important role in highway planning, transportation 

agencies need tools to integrate environmental 

considerations into their policies, processes, 

procedures, practices, and projects. 

As part of its commitment to promote integrated 

planning that improves transportation safety and 

addresses environmental, social, and economic needs, 

FHWA developed the Infrastructure Voluntary 

Evaluation Sustainability Tool (INVEST). Available 

at www.sustainablehighways.org, INVEST is being 

used by 29 agencies in 25 States and Washington, 

DC including DOTs, MPOs, councils of government, and public works departments. Other partners 

use INVEST to evaluate and integrate sustainability 

into their programs and projects.

The FHWA Eastern Federal Lands Highway 

Division (EFL) used concepts from INVEST’s 

Project Development (PD) module in their 

Construction Winter Training Program. The goal of 

this training was to increase awareness and facilitate 

greater discussion about sustainability, and to further 

integrate sustainability considerations into project 
Federal Highway Administration 29

planning, design, and construction. Using INVEST, 

EFL found that the Mulligan Road project, located 

in Fairfax Country, Virginia, excelled in criteria 

related to context sensitivity, pedestrian and bicycle 

access, ecological connectivity, long-life pavement, 

environmental training, and construction quality 

control. Other criteria identified as potential areas 

for improvement with relatively low additional effort 

included site vegetation, reducing and reusing 

materials, and construction waste management. 

Newly reconstructed and environmentally sensitive business-tourist corridor with new vehicle lanes, pedestrian pathways, and structural 

retaining walls, developed as part of an FHWA project. (Image source: FHWA) 
30 The FHWA 2015 R&T Story: Research and Innovative Solutions for the Nation’s Highway Challenges

INVEST has helped show EFL staff the benefits of 

integrating sustainable practices.

The Illinois Tollway Authority used INVEST to 

complete an 18-project retrospective evaluation that 

will set baselines and minimize environmental 

impacts of new roadway construction by reusing 

and recycling materials, reducing energy costs, and 

measuring sustainability of practices. Illinois Tollway 

will incorporate the INVEST tool into the planning, 

development, and operations lifecycle of the 15-year, 

$12 billion Move Illinois Program. INVEST will 

allow the agency to identify institutional and other 

barriers that may prevent it from implementing sustainable practices during the construction phase. 

Similarly, Ohio DOT used the INVEST PD module 

during the reconstruction of the Cleveland Innerbelt 

Bridge/I-90, also known as the George V. Voinovich 

Bridge. It was critical for Ohio DOT to achieve 

sustainability for this high-priority project, and the 

agency focused on major savings in fuel, steel, water, 

and waste. INVEST was so successful in helping 

Ohio DOT realize these savings in Phase 1 of the 

project, it was used to ensure contractor performance 

during Phase 2. By requiring INVEST as part of the 

Request for Proposals for the design-build contract, 

Ohio DOT gave contract bidders a strong incentive to include sustainability practices as part of their 

proposals while also keeping costs competitive. 

The Massachusetts DOT used the INVEST PD 

module to evaluate the Casey Arborway Project, 

which could replace a 1950s-era elevated highway 

with an at-grade roadway with strong pedestrian 

connectivity. Arizona DOT (ADOT) is using 

INVEST’s PD module to conduct an assessment of 

its statewide roundabout program. Particular criteria 

that Arizona plans to examine further include: green 

infrastructure and low-impact development, bike and 

pedestrian mobility, and context-sensitive solutions. 

Arizona found that INVEST helped ADOT further 

internal lines of communication, sparking new types 

of discussion and collaboration.

Leading the Way to More Environmentally 

Sustainable Highways

The safety, long-term economic viability, and continued operation of the highway system and well-being 

of its users are affected by environmental factors. 

FHWA R&T focuses on environmental sustainability 

as a key challenge because motor vehicles are a significant source of greenhouse gas emissions and roadway 

construction can adversely affect wildlife habitats. 

Environmental sustainability is based on the principle 

that everything needed for peoples’ survival and wellbeing depends, either directly or indirectly, on the 

natural environment. Sustainability creates and 

maintains the conditions under which humans and 

the natural world can exist in productive harmony, 

allowing the fulfillment of social, economic, and other 

requirements of present and future generations. 

Sustainability is essential for making sure the Nation 

has and will continue to have water, raw materials, 

and resources to protect human health and the 

environment.20 FHWA’s strategic approach to R&T 

comprehensively addresses environmental sustainability, and seeks new ways to increase efficiency and 

collaboration while decreasing impacts to the natural 

environment and wildlife.

For More Information

The following Web sites are provided for additional information, and 

further highlight the transportation challenges and FHWA activities 

discussed above.

Road Revegetation: An Integrated Approach to Establishing Native 

Plants: http://www.nativerevegetation.org/. 

FHWA Recycling Policy: http://www.fhwa.dot.gov/pavement/recycling/. 

FHWA Environmental Review Toolkit: http://www.environment.fhwa.

dot.gov/index.asp. 

FHWA INVEST Version 1.0: https://www.sustainablehighways.org/. 
Federal Highway Administration 31

18. Federal Highway Administration (2007). Roadside Revegetation: An 

Integrated Approach to Establishing Native Plants. Washington, DC. 

Accessed online: February 18, 2015. 

(https://www.wfl.fhwa.dot.gov/programs/td/publications/documents/

reveg-documents/roadside-revegetation-manual.pdf)

19. Mastro, Lauren L.; Conover, Michael R.; and Frey, S. Nicole. (2008). 

“Deer–Vehicle Collision Prevention Techniques.” 

Human–Wildlife Interactions. 

20. United States Environmental Protection Agency (2015). “What is 

Sustainability?” (Web page) Washington, DC. Accessed online: 

February 18, 2015. (http://www.epa.gov/sustainability/basicinfo.htm)
32 The FHWA 2015 R&T Story: Research and Innovative Solutions for the Nation’s Highway Challenges

Examples of FHWA research 

and innovation delivery 

activities:

• Creating Productive Roadways—

Developing an Advanced Energy 

Production, Storage, and Distribution 

System

• Developing Connected Vehicle 

Technology to Improve Safety 

and Mobility

• Training Transportation Decisionmakers 

and Practitioners

• Studying the Next Generation

of Travelers

• Finding New Ways to Fund 

Transportation Projects

Above: Pre-cast concrete deck panels are aligned 

on top of steel bridge girders as part of an FHWA 

Highways for LIFE project implemented by Minnesota 

DOT to replace a deteriorated bridge using ABC 

techniques. Below: Solar-powered lamps are installed 

along a pedestrian walkway in proximity to a busy 

highway. (Image source: FHWA)

Preparing 

for the Future 

Looking beyond today’s challenges to 

anticipate the emerging issues of tomorrow.

FHWA is the agency within the USDOT that supports 

State and local governments in the design, construction, 

and maintenance of the Nation’s highway system 

(Federal Aid Highway Program) and various Federal 

and Tribal-owned lands. Through financial and technical 

assistance to State and local governments, FHWA is 

responsible for ensuring that America’s roads and highways 

continue to be among the safest and most technologically 

sound in the world.

The challenges facing transportation agencies are 

continuously changing as technology, demographics, the 

environment, and the economy evolve. FHWA forecasts 

transportation change by examining evolving passenger and 

freight transportation needs against a range of scenarios. 

FHWA assists the transportation workforce by identifying 

emerging trends such as innovative finance and program 

delivery methods, and new techniques for long-range policy 

planning. This is accomplished, in part, by building strong 

relationships with researchers to more quickly track and 

identify the benefits of new scientific discoveries.
Federal Highway Administration 33

Research Activities

From developing infrastructure that will help meet 

future energy demands to improving safety and 

mobility through connected vehicle technology, 

highway finance, and taxes—FHWA research 

anticipates tomorrow’s highway challenges through 

industry study and engagement. 

Creating Productive Roadways—Developing 

an Advanced Energy Production, Storage, and 

Distribution System

Imagine using the public right-of-way as a source 

of energy. The EAR Program has done just that, 

funding the Roadway Wind/Solar Hybrid Power 

Generation and Distribution System (RHPS). Created in partnership with the University of Nebraska, 

the project is developing an intelligent power system 

that may provide cost-effective, efficient, and reliable renewable electric power production, storage, 

and distribution. RHPS has the potential to reduce 

highway maintenance and operating costs, and provide backup for traffic control systems during power 

outages, thereby improving operational efficiency 

and reliability.

RHPS has at its core a wind and solar hybrid power 

system that can attach to existing structures for traffic signals, roadway lighting, and overhead road signs. 

Each signal will feature solar panels and a windturbine generator to produce power for onward 

distribution through the electric power grid. A power-management system will be developed to manage 

production, storage, distribution, and consumption 

of energy based on demand interacting with roadway 

communication and networking infrastructure.

The project represents significant technological 

advancement in renewable energy and production, 

storage, and distribution. By utilizing existing infrastructure to produce and distribute power, RHPS is 

expected to have an impact on the development of 

next-generation smart electric power grids. RHPS 

will significantly reduce the overall power needed to 

operate roadway systems, and create a more efficient 

network. It will also offer a source of backup power 

for the transportation system, thus reducing the risk 

of blackouts. 

At a field test site in Lincoln, Nebraska, RHPS 

equipment was installed on 1 of 4 of the traffic 

signals in an intersection, and the lifecycle savings 

at the intersection was estimated at $15,000 over 20 

years with a break-even time of roughly 10 years.

FHWA is also researching ways to harvest piezoelectric energy through pavement applications in 

the public right-of-way that will capture the excess 

energy lost in pavement deformation and vibration 

created by cars, trucks, and other vehicles on the 

Nation’s highways. Currently, FHWA is studying 

the feasibility of piezoelectric generation technologies 

as an energy harvesting option through laboratory 

testing, analytical modeling, and field testing. Results 

of this work will be evaluated to determine the 

appropriate applications for this technology. 

Developing Connected Vehicle Technology to 

Improve Safety and Mobility 

In an effort to improve safety and efficiency for 

freeway merging, FHWA funded a project to develop 

and evaluate three algorithms related to dynamic lane 

control, gap-responsive metering, and merge control 

using connected vehicle communications. Researchers 

used an enhanced simulation environment to evaluate 

the algorithms’ safety and efficiency impacts under 

different scenarios of vehicles with and without 

vehicle-to-vehicle and vehicle-to-infrastructure 

communication equipment.

The freeway merge assistance algorithms are part 

of a larger network of USDOT initiatives. The goal 

of the initiatives is to develop connected vehicle 

technology that improves the safety, mobility, and 

sustainability of roadways. FHWA R&T also supports this important effort in areas of safety and the 

development of connected vehicle research.
34 The FHWA 2015 R&T Story: Research and Innovative Solutions for the Nation’s Highway Challenges

Training Transportation Decisionmakers 

and Practitioners

Recognizing that tomorrow’s innovative project 

designs come from a knowledgeable and confident 

workforce, FHWA created the IPD (Innovative 

Program Delivery) Academy. The IPD Academy 

provides decisionmakers and practitioners with the 

tools and knowledge needed to explore and implement innovative strategies to deliver transportation 

programs and projects. 

Launched in 2009, the IPD Academy provides a 

comprehensive selection of courses and curricula, 

including webinars, workshops, and expert assistance. 

The IPD Academy helps USDOT’s professional 

staff integrate innovative delivery strategies into 

their specific disciplines and focus areas. Attendees 

learn strategies for overcoming resource constraints, 

addressing energy and environmental considerations, 

and promoting efficiencies in program delivery. The 

IPD Academy also delivers training to professionals 

at State and local transportation agencies. The IPD 

Academy has delivered more than 140 webinars 

registering 27,000 participants representing all 50 

States, the District of Columbia, and Puerto Rico. 

Webinar participants have included financial managers and specialists, major project engineers, Federal 

Transit Administration regional offices, the Federal 

Railroad Administration, and industry experts in 

freight, legal, planning, and civil rights. 

Studying the Next Generation of Travelers

What will personal travel look like in the future and 

how will it influence system demand down the road? 

As part of a strategic objective to evaluate and analyze 

current and emerging issues that will affect surface 

transportation, the FHWA Transportation Futures 

Team finalized a report that examines trends related to 

the travel behavior of young people between the ages 

of 15 and 26. This information will be used to develop 

policy recommendations. The desired outcome will be 

improved travel forecasts of demand, vehicle usage, 

and how new transportation technologies impact 

personal travel. The team understands that personal 

travel will be influenced by a combination of various events, demographic and socioeconomic factors, 

generational social norms, and adaptation of people 

to new technologies and travel options. This comprehensive research incorporates a broad spectrum 

of perspectives.

The work completed under the travel behavior study 

provides both a quantitative and qualitative evaluation of current and emerging travel shifts by generation. Of particular interest are the impacts of new 

technologies and social trends that may influence 

mode choice, trip making, trip planning, and overall 

perceptions of vehicle travel among youth in the U.S. 

The results of the analyses will be used to develop 

profiles of the next generation of travelers, and will 

be considered in future travel trend forecasts and 

travel scenario development. The information presented is ultimately intended to be used as a guide in 

the development of current and future transportation 

policies regarding personal travel.

Jeremy Walcott, P.E., gives an overview of a FHWA Highways for 

LIFE construction project at a showcase held at the Florida DOT 

District 5 office. (Image source: FHWA) 
Federal Highway Administration 35

Finding New Ways to Fund 

Transportation Projects 

Despite record levels of investment in surface transportation infrastructure in recent years, traditional 

funding sources have not kept pace with the investment demands of an aging and increasingly complex 

U.S. transportation system. Transportation officials at 

all levels of government will continue to seek 

innovative ways to fund improvements to the 

Nation’s transportation system. 

For almost two decades, the federal government 

has responded to this investment gap by providing 

new techniques that complement and enhance existing grant reimbursement programs. By providing 

FHWA’s Highways for LIFE program supported the Missouri DOT’s construction of the Christopher Bond Bridge through an innovative design 

build procurement process. The bridge foundations were designed and constructed using cost-effective technical engineering solutions that 

led to significant savings in time and money. (Image source: FHWA)
36 The FHWA 2015 R&T Story: Research and Innovative Solutions for the Nation’s Highway Challenges

individualized tools and technical assistance, FHWA 

helps State and local agencies assess the applicability 

of available financing options for complex projects so 

that they can build the highways and bridges necessary to keep pace with a growing Nation. 

FHWA’s Project Finance Primer describes those 

techniques and provides examples of their application 

by State and local partners. The Primer will continue 

to evolve and lay the groundwork for the identification of additional innovative strategies for financing 

surface transportation investments into the future. 

The Ohio River Bridges project, a bi-State collaboration between Kentucky and Indiana, is one 

example of how State and local partners can use 

innovative financing strategies to complete complex 

highway infrastructure projects. Developed via a 

joint planning effort, the two States approached their 

respective bridge projects from different financial 

perspectives. Kentucky chose to finance its toll bridge 

using bonds, including Grant Anticipation Revenue 

Vehicles, while Indiana committed to make availability payments to a long-term concessionaire that 

obtained financing in part with Private Activity 

Bonds. When completed in 2018, the two new bridges 

over the Ohio River will link Louisville and southern 

Indiana. The new bridges are expected to improve 

traffic flow, reduce congestion, improve safety, and 

FHWA’s Highways for LIFE program supported the placement of the pier table on the deck of the Christopher Bond Bridge through an 

innovative design build procurement process, providing cost savings and flexibility in the bridge construction schedule. (Image source: FHWA)
Federal Highway Administration 37

enhance transit service. Innovative financing accelerated project delivery, evenly distributed project costs, 

provided additional financing options, and leveraged 

federal grant funds using private-sector equity 

and expertise. 

For more information on the project financing, 

please visit FHWA’s project finance Web site, which 

focuses on alternative financing mechanisms. In 

addition, the IPD Web site has information detailing 

Public-Private Partnerships, and the Transportation 

Infrastructure Finance and Innovation Act, which 

provides credit assistance for significant projects.

Anticipating Tomorrow’s Highway Challenges

FHWA R&T is transforming today’s big ideas into 

the innovations to meet future transportation 

challenges, ensuring that they are incorporated into 

the construction, maintenance, and operation of the 

Nation’s highway system. FHWA’s strategic approach 

to innovation means that preparing for the future is 

an essential part of the Agency’s efforts.

For More Information

The following Web sites are provided for additional information, and 

further highlight the transportation challenges and FHWA activities 

discussed above.

EAR Program Fact Sheet—Creating Productive Roadways: http://

www.fhwa.dot.gov/advancedresearch/pubs/12063/index.cfm. 

Fact Sheet—Efficient and Safe Merging Solutions—Advanced 

Freeway Merge Assistance: Harnessing the Potential of Connected 

Vehicles: http://www.fhwa.dot.gov/advancedresearch/pubs/14045/

index.cfm.

IPD Academy: An Introduction: http://www.fhwa.dot.gov/ipd/pdfs/

fact_sheets/h_pdi_academy_1_19_12.pdf.

FHWA Transportation Futures—Future Uses of Highway Rights of 

Way: http://www.fhwa.dot.gov/policy/otps/transfutures.cfm. 

FHWA Project Finance Primer 2010: http://www.fhwa.dot.gov/ipd/

finance/resources/general/default.aspx. 

Federal Highway Administration 39 

Research Moves the 

Nation Forward 

Conclusion

Laboratory assessment and research 

are critical pieces of FHWA’s work in 

ensuring that the Nation’s roadways and 

infrastructure are safe, sustainable, 

and cost-effective in the years ahead. 

(Image source: FHWA) 

The results and benefits of FHWA’s research efforts can be 

seen across the country in many of the projects discussed in 

this report. Within FHWA, hundreds of research projects 

are underway to develop innovations and solve the country’s 

pressing transportation problems. Because transportation 

comprises many disciplines, from human factors to structural 

impacts to environmental and safety impacts, an extensive 

depth and breadth of knowledge is necessary to address the 

challenges facing our transportation system.

FHWA professionals are known worldwide for their 

expertise, and they collaborate with national and international transportation agencies and communities to conduct 

and review research projects and technology transfer 

initiatives within a highly collaborative system. Because 

of the complexity of the system, setting the right research 

agenda is critical to making an impact across the entire 

transportation system. As public expectations change and 

demand on the highway system continues to increase, 

FHWA’s R&T leadership will play a critical role in 

anticipating future challenges and providing the highway 

community with innovations to maintain and improve the 

safety and mobility of the highway system and economic 

prosperity of the Nation.

For more information or to provide feedback, please 

visit the FHWA research Web site at www.fhwa.dot.gov/

research.

To continue economic 

growth and serve a 

growing population, the 

U.S. must invest not only 

in its transportation system 

but also in research to 

improve safety, protect 

the environment, reduce 

congestion on crowded 

roadways, and provide 

alternative methods of 

moving people and goods. 
Publication No. FHWA-HRT-14-091

HRTM-20/9-14(2M)E