EAR PROGRAM—RESEARCH ASSOCIATES PROGRAM|A
B|EAR PROGRAM —RESEARCH ASSOCIATES PROGRAM

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Cover photos

Left: Photo of a masonry-faced geosynthetic-reinforced soil (GRS) column, part of 

a series of large-scale performance tests that helped quantify the durability and 

serviceability of GRS structural components of bridge foundations under everyday 

loads (see page 4).

Right: Image showing the nucleation of ettringite mineral in the interfacial transition 

zone, part of a research objective to develop inorganic curing compounds for 

addressing the shortcomings of current organic membrane-forming curing 

compounds in pavement construction (see page 5).
EAR PROGRAM—RESEARCH ASSOCIATES PROGRAM|1

The Research Associateship Program 3

Breakthrough Concepts in Materials Science 4

Performance of Geosynthetic-Reinforced Soils at the Service Limit State 4

Use of Inorganic Coatings as Curing Compounds 5

Developing New Vehicle–Tire and Contact Friction Models 6

Comprehension and Development of Nano-Additives to Judicially 

Improve the Interfacial Region in Concrete and Asphalt 7

Human Behavior and Travel Choices 8

Integrating Driving Simulation and Other Behavioral Data: 

Assessment of Driver Behavior and Performance 8

Operational and Safety Analyses of Alternative Intersection/ 

Interchange Designs 9

Utilizing Naturalistic Driving Data and Highway Safety Information System 

to Advance Highway Crash Data Modeling Concepts and Methods 11

Technology for Assessing Performance 12

Developing Frameworks of Performance-Based Asphalt Mix Design 12

Developing and Implementing Dynamic Junction Control System 

in the United States 13

Tensile Response of Ultra-High Performance Concrete: 

Validation of Characterization Methods 14 

Prediction of Pavement Temperature Profiles Using Surface 

Temperatures: An Analytical Approach With Model Validation 

Based on Long-Term Pavement Performance Data 15

Contents

Since 1954, the National Research Council (NRC) has conducted the Research Associateship 

Program (RAP) in cooperation with sponsoring Federal laboratories and other approved 

participating research organizations. RAP provides highly skilled and exceedingly promising 

postdoctoral and senior scientists and engineers with opportunities to research problems that are 

compatible with the interests of sponsoring laboratories. RAP offers recent doctoral graduates opportunities for concentrated research with selected members of permanent, professional, laboratory staff 

and allows them to contribute to the overall efforts of the laboratories.

The Federal Highway Administration (FHWA) has participated in RAP since 1992. To supplement the 

expertise of permanent staff, FHWA’s Turner–Fairbank Highway Research Center (TFHRC), through its 

Exploratory Advanced Research (EAR) Program, invites researchers with appropriate backgrounds to 

investigate specific problems on a short-term basis across a wide range of topics and disciplines.

NRC provides a process for selecting candidates on a competitive merit basis and, subsequently, for 

administration of the resident fellows during their tenures at FHWA. The process begins with a 

prospective FHWA adviser developing a proposed research opportunity. The adviser then coordinates 

with FHWA leadership to approve the opportunity and forward the proposed research to NRC. All 

research opportunities require an abstract that relates to exploratory advanced research and is of 

specific relevance to the FHWA research program. One of the significant benefits of this process is that 

it encourages interaction between government researchers and new researchers who are using cutting-edge approaches and research tools in their work.

RAP provides opportunities for FHWA’s EAR Program to advance research methods used at TFHRC. 

Over the years, associates have researched topics as diverse as nano-additives for concrete and asphalt, alternative intersection and interchange design, and modeling to predict collisions based on 

driver behavior and environmental conditions.

The following pages contain summary descriptions of some of the research projects that the 

resident fellows have been involved in during their respective tenures at FHWA.

The EAR Program addresses the need for longer term, higher risk research with the potential 

for long-term improvements to transportation systems—improvements in planning, building, 

renewing, and operating safe, congestion-free, and environmentally sound transportation facilities. 

The EAR Program seeks to leverage advances in science and engineering that could lead to 

breakthroughs for critical, current, and emerging issues in highway transportation—where there 

is a community of experts from different disciplines who likely have the talent and interest in 

researching solutions and who likely would not do so without EAR Program funding.

EAR PROGRAM—RESEARCH ASSOCIATES PROGRAM|3

The Research Associateship Program
4|EAR PROGRAM —RESEARCH ASSOCIATES PROGRAM

Breakthrough Concepts in Materials Science

PROJECT: Performance of Geosynthetic-Reinforced Soils at the Service Limit State

ASSOCIATE: Danial Esmaili

SCHOOL: University of Oklahoma 

PERIOD: December 2014–October 2015 

OBJECTIVE: To analyze large-scale performance test results to evaluate the effect of tensile strength, vertical reinforcement 

spacing, facing elements, and backfill properties on deformations of geosynthetic-reinforced soil under typical 

bridge support service pressures. 

ADVISER: Jennifer E. Nicks, FHWA Office of Infrastructure Research and Development

SUMMARY: Geosynthetic-reinforced soil (GRS) technology 

consists of closely spaced layers of geosynthetic reinforcement 

and compacted granular fill material. This method of using 

geosynthetics to reinforce foundations is a proven alternative to 

the construction of deep foundations, depending on the site 

conditions. GRS is widely used for a variety of earthwork projects, 

particularly in GRS-integrated bridge system (IBS) applications. 

GRS-IBSs are economical and easy to design; they can be built in 

a variety of weather conditions and can be modified to 

accommodate characteristics of varying site conditions. An 

important geotechnical feature of any bridge foundation, 

including GRS bridge elements, is the service limit state (SLS), 

which ensures the durability and serviceability of a bridge and its 

structural components under everyday loads for the design life. 

The SLS for GRS abutments primarily includes vertical settlement, 

lateral deformation, and reinforcement strain. Notwithstanding 

their widespread use in construction, the SLSs of GRS abutments 

have not been well defined. 

Danial Esmaili’s research project involved analyzing the results of 

a series of 13 large-scale column experiments (also called 

performance tests or minipier tests) conducted to help quantify 

both the SLS and ultimate limit state for GRS. The experiments 

were conducted on GRS piers consisting of different backfill 

materials, geosynthetic reinforcement strengths, and 

reinforcement spacing (the thickness of backfill between 

reinforcement layers). Some test piers were constructed with 

concrete masonry facing; others had no facing. All GRS 

configurations were tested to failure, with the focus of this study 

on the performance at loads of 200 kPa (recommended allowable 

GRS bearing pressure) and 400 kPa (to test performance at 

extreme service loading). Key research findings of these 

experiments are that:

• GRS piers built with higher strength backfill undergo less lateral 

and vertical deformation.

• Settlement and lateral displacement at 200 kPa, depending on 

composition of test columns, ranged from 8.3 mm to 33.9 mm 

and 3.0 mm to 10.1 mm, respectively.

• Reinforcement spacing plays a larger role than does 

reinforcement strength in lateral and vertical deformation.

• Lateral movement of pier walls is greatest in the top third of

the composite.

• Limiting-bearing pressure to 10 percent of the estimated 

bearing resistance of the GRS abutment will limit axial strains to 

within 0.5 percent of the abutment.

IMPACT: Data gathered through these experiments will help 

engineers more reliably design GRS-IBS projects without having 

to conduct complex and expensive laboratory testing.

RESOURCES: Several publications and papers resulted from this 

RAP research. They are outlined below.

Nicks, J. E., Esmaili1, D., & Adams, M. T. (2016). Deformations of geosynthetic reinforced soil under bridge service loads. Geotextiles and 

Geomembranes, 44(4), 641–653.

Adams, M. T., Ooi, P. S. K., Nicks, J. E. (2014). Mini-pier testing to estimate 

performance of full-scale geosynthetic reinforced soil bridge abutments. Geotechnical Testing Journal, 37(5).

Minipier tests 

helped quantify 

SLS for GRS 

with (upper 

photo) and 

without (lower 

photo) concrete 

masonry facing.
EAR PROGRAM—RESEARCH ASSOCIATES PROGRAM|5

Breakthrough Concepts in Materials Science

PROJECT: Use of Inorganic Coatings as Curing Compounds

ASSOCIATE: Jessica Silva

SCHOOL: University of Wisconsin–Madison

PERIOD: September 2012–December 2013

OBJECTIVE: To develop inorganic curing compounds to address the shortcomings of current organic membrane-forming 

curing compounds. 

ADVISER: Jack S. Youtcheff, FHWA Office of Infrastructure Research and Development

SUMMARY: Proper curing is a vital post-treatment process when 

constructing durable concrete pavements. This is because water 

loss by evaporation through exposed surfaces can result in mechanical or chemical deficiencies in the final surface of the concrete 

product. Existing membrane-forming curing compounds are widely 

used to form a physical barrier to prevent the migration of 

water during the first few hours of concrete placement; however, 

these membranes do not always form a continuous coating, may 

degrade after environmental exposure, and provide little protection 

of the concrete section at later stages of the pavement’s service 

life. Jessica Silva’s research project examined the use of inorganic 

curing compounds to address the shortcomings of current organic 

compounds. These inorganic curing compounds, prepared from 

metal-oxide materials, can react with the concrete surface to 

form durable coatings and hydration products. The compounds 

may also impart beneficial characteristics to the roadway and 

provide improvements to the pavement long after traditional 

membranes. Silva examined changes occurring to the air and 

mortar and mortar and aggregate interface, in addition to the 

porosity, density, and chemical makeup of the cement paste. 

Silva also ensured that the inorganic curing compounds under 

development would not adversely affect the concrete material. 

As part of this research project, Silva used a traceable element 

to better understand the effect of the compound as it penetrates 

the concrete.

IMPACT: This research could represent a paradigm shift in the 

world of curing compounds. In addition, if the material developed as a result of this research is not ultimately useful as a 

curing compound, it may still prove useful to enhance general 

concrete characteristics.

RESOURCES: Several publications and papers resulted from this 

RAP research. They are outlined below.

Silva, J. M. S., Youtcheff, J., & Arnold, T. (2013). Utilizing sol-gel nanoparticles in concrete curing to improve surfaces. National Research Council 

Research Associateship Programs Newsletter, 14–16.

Munoz, J. F., Silva J. M. S., Perry L., Youtcheff, Y., & Sobolev K. (2014). Interaction of amorphous nano-aluminosilicates with cement pore solution 

and the effect on the early hydration reaction of portland cement. 

Proceedings of the Fifth International Symposium on Nanotechnology in 

Construction.

Nucleation of 

ettringite mineral 

in the interfacial 

transition zone.
6|EAR PROGRAM —RESEARCH ASSOCIATES PROGRAM

Breakthrough Concepts in Materials Science

PROJECT: Developing New Vehicle–Tire and Contact Friction Models

ASSOCIATE: Emmanuel Bolarinwa

SCHOOL: University of Birmingham

PERIOD: September 2010–September 2015

OBJECTIVE: To use a model-based approach for investigating the effect of tire–pavement contact friction on the safety performance 

of vehicles. 

ADVISER: James A. Sherwood, FHWA Office of Infrastructure Research and Development

SUMMARY: The effective management of critical pavement surface 

characteristics, such as friction and texture, has been shown to 

help prevent or reduce the consequences of rear-end and runoff-the-road crashes. Although high-friction surfaces can lead to 

increased numbers of dry pavement rollovers, they also lead to 

fewer wet pavement run-off-the-road crashes and tend to have 

fewer crashes involving fatalities and serious injuries. For his research project, Emmanuel Bolarinwa implemented a model-based 

approach to investigate the effect of variations in vehicle– and 

tire–pavement friction on vehicle safety performance, such as 

stopping distances during braking. He considered the interactions 

among key crash causative factors and predicted vehicle performance and stability metrics. Bolarinwa examined a vehicle simulation package containing various values for pavement friction and 

texture inputs. For model verification, Bolarinwa obtained vehicle 

data and crash information from the Highway Safety Information 

System (HSIS) and the second Strategic Highway Research Program’s naturalistic driving study. He then used the model to develop theoretical thresholds for pavement friction and texture inputs 

(i.e., the minimum values when crash rates have been found to increase at a significantly higher rate). Bolarinwa analyzed results 

from the simulation to extract vehicle performance and safety 

metrics as possible indicators of the onset of vehicle crashes for 

different vehicle types and a variety of road sections and geometries.

IMPACT: This research should lead to enhanced road safety, ensuring 

significant savings in cost and human lives by managing pavement 

friction. The research directly contributes to FHWA’s strategic 

safety improvement program by predicting friction threshold 

values to determine conditions when a pavement should be investigated for maintenance intervention. Bolarinwa’s research will 

lead to better characterization of the effects of a broad range of 

human, vehicle, and environmental factors on crash outcomes. 

It will also provide a basis for evaluating practices related to pavement surface material parameters and roadway geometry. FHWA 

will ultimately use the results of this research to develop new 

vehicle crash models, which will be of value to safety engineers 

working on state highway safety improvement programs. In 

addition, the results could be used to change pavement design 

standards to select the best pavements in terms of safety.

ONGOING RESEARCH: Bolarinwa will continue research into the 

development of theoretical threshold values for pavement friction 

and develop procedures for predicting stopping distances based 

on the friction of the pavement surface. The long-term goal is to 

reduce fatal and severe (incapacitating injury) crashes, by prescribing levels of pavement friction and macrotexture.

RESOURCES: Several publications and papers resulted from this 

RAP research. They are outlined below.

Uzunsoy, E., Bolarinwa, E., Olatunbosun, O., & He, R. (2014). Investigating 

vehicle behavior on a sloped terrain surface. SAE Technical Paper 2014-

01-0857.

Yang, X., Olatunbosun, O., Ramos, D. G. P., & Bolarinwa, E. (2013). Experimental investigation of tire dynamic strain characteristics for developing 

strain-based intelligent tire system. SAE International Journal of 

Passenger Cars–Mechanical Systems, 6(1), 97–108.

Bolarinwa, E. O., Mahadevaiah, U., Marzougui, D., & Opiela, K. S. (2012). The 

development of an enhanced finite element tire model for roadside 

safety hardware assessment. Proceedings of the Institution of Mechanical 

Engineers, Part K: Journal of Multi-Body Dynamics, 226(3), 206–219.

Bolarinwa, E. O. (2014). Material and geometrical characterization for 

FE tire modeling and simulation. Paper presented at the 2014 Tire 

Technology Expo Conference, Cologne, Germany.

Bolarinwa, E. O. (2013). Development of an FE tire model for vehicle 

crash simulations. Paper presented at the 2013 Tire Technology Expo 

Conference, Cologne, Germany.

Bolarinwa, E. O. (2013). Experimental investigation of vehicle behavior on a 

sloped-terrain surface. Paper presented during the SAE 2013 World 

Congress and Exhibition, Detroit, MI.

Bolarinwa, E. O. (2012). Role of tire testing in efforts to develop improved 

finite element models to support crash simulation. Workshop on 

Improving the Modeling of Tire, Steering and Suspension Systems in 

Angular Crashes, FHWA Turner–Fairbank Highway Research Center, 

McLean, VA.

Bolarinwa, E. O. (2011). The development of an enhanced finite element tire 

model for vehicle crash simulations. Paper presented at the 30th Annual 

Conference on Tire Science and Technology, Akron, OH.

Bolarinwa, E. O. (2011). Role of tire testing in efforts to develop improved 

finite element vehicle models to support crash simulations. Paper presented at the 2011 Tire Technology Expo Conference, Cologne, Germany.

A simulation model 

for investigating 

vehicle behavior 

on a sloped terrain 

surface.
EAR PROGRAM—RESEARCH ASSOCIATES PROGRAM|7

PROJECT: Comprehension and Development of Nano-Additives to Judicially Improve the Interfacial Region in Concrete and Asphalt

ASSOCIATE: Jose Muñoz

SCHOOL: University of Wisconsin–Madison

PERIOD: April 2010–March 2013 

OBJECTIVE: To investigate how judicially applied coatings on the surface of the aggregates of different nano-additives 

can improve the interfacial region in concrete and asphalt. 

ADVISER: Jack S. Youtcheff, FHWA Office of Infrastructure Research and Development

SUMMARY: Jose Muñoz examined a method to enhance the area 

of contact between cement-paste aggregates and asphalt aggregates, known as the interfacial region. This is one of the most 

vulnerable areas of concrete and asphalt, potentially affecting 

the overall performance of pavement. The durability of concrete is 

highly influenced by its pore structure, specifically a highly porous 

area known as the interfacial transition zone (ITZ). Large fractions 

of the microcracks occurring in concrete are associated with the 

ITZ; therefore, improving the strength of the ITZ could significantly 

improve concrete durability. Traditional approaches to the problem, 

involving the successive addition of different silicon or aluminumbased materials, have been inefficient and costly. Muñoz based his 

research on the theory that nanoparticles added as nanoporous 

films, and when judiciously placed on the aggregate surface, can 

greatly improve the ITZ and thereby the performance of the concrete. He investigated changes triggered by nanoporous thin films 

in the chemistry and morphology of the hydration products located 

at the aggregate–cement-paste interface. Muñoz developed 

a model to determine two-dimensional spatial distribution of 

cement hydration phases and to study the aggregate–cement-paste interface in concrete. In addition, Muñoz developed a 

new sol-gel synthesis (a method for producing solid materials 

from small molecules) to produce “nano-aluminosilicate” gels 

with a controlled silicon-to-aluminum ratio. Muñoz also studied the 

effect of these nano-aluminosilicate gels with different silicon-toaluminum ratios on the hydration reaction of portland cement.

IMPACT: The development of new nano-additives, together with a 

new method for applying them in concrete, is expected to help create materials with less water and chloride penetrability and higher 

mechanical strength and resistance to cracking. This is expected to 

lead to the creation of construction materials with improved characteristics and less energy demand for maintenance operations. The 

application of nanoparticles in concrete and asphalt, using dip- or 

spray-coating methods, offers several advantages when compared 

with the traditional addition of nanoparticles as powder additives. It 

is an easier and safer application method—fewer additives are 

required, which reduces costs—and the technology is already available. In addition, this technology can have a positive impact in locations with limited or marginal-quality aggregate sources. For example, these nano-additives can be used to improve performance of 

currently marginal aggregates, such as natural aggregate with significant contents of clay minerals strongly adhered to their surface.

ONGOING RESEARCH: Muñoz continues to study the effect of the 

nanoparticles in concrete pore solution at early stages of hydration. In addition, he also performed research with the U.S. Army 

Engineer Research and Development Center to characterize the 

ITZ modified with nanoparticles.

RESOURCES: Several publications and papers resulted from this 

RAP research. They are outlined below.

Muñoz, J. F., Meininger, R. C., & Youtcheff, J. (2010). New possibilities and 

future pathways of nanoporous thin film technology to improve concrete performance. Transportation Research Record, Journal of the 

Transportation Research Board, 2142, 34–41.

Muñoz, J. F., Yao, Y., Youtcheff, J., & Arnold, T. (2011). Nanotechnology to 

improve aggregate performance. National Research Council, Research 

Associateship Program Newsletter.

Muñoz, J. F., Yao, Y., Arnold, T., & Youtcheff, J. (2013). Mixtures of silicon 

and aluminum oxides to optimize the performance of nanoporous 

thin films in concrete. Cement and Concrete Composites, 48.

Munoz, J. F., Silva, J. M. S., Perry, L., Youtcheff, Y., & Sobolev, K. (2014). 

Interaction of amorphous nano-aluminosilicates with cement pore 

solution and the effect on the early hydration reaction of Portland 

cement. Proceedings of the Fifth International Symposium on Nanotechnology in Construction.

Balachandran, C., Muñoz, J. F., Arnold, T., & Youtcheff, J. (2014). Potential 

application of surface enhanced Raman spectroscopy as a tool to study 

cementitious materials. Proceedings of the Fifth International Symposium on Nanotechnology in Construction.

Backscattered electron images of a potassium sulfate crystal 

formed inside of a silica gel in the interfacial transition zone.

Breakthrough Concepts in Materials Science
8|EAR PROGRAM —RESEARCH ASSOCIATES PROGRAM

PROJECT: Integrating Driving Simulation and Other Behavioral Data: Assessment of Driver Behavior and Performance

ASSOCIATE: Alicia Romo

SCHOOL: The University of Texas at El Paso

PERIOD: September 2013–August 2015

OBJECTIVE: To develop methods that will use data from various sources, such as driving simulator experiments, crash 

databases, and naturalistic driving studies, to gain comprehensive understanding about road-user behaviors. 

ADVISER: C. Y. David Yang, FHWA Office of Safety Research and Development

SUMMARY: A high percentage of transportation incidents and 

vehicle crashes are caused by human errors. As a result, it is 

important to continue investing in research resources to gain a 

comprehensive understanding of human errors and to try to 

answer the question, “Why do drivers and travelers do what they 

do?” A number of different datasets have recently become available to analyze human errors; however, these datasets point 

in different directions within different areas of interaction. Alicia 

Romo’s research project is focused on finding methods to combine data from different sources to gain better understanding 

about road-user behavior. During the first year, Romo conducted 

a comprehensive literature review and summarized information 

from more than 100 technical journals and reports about various 

methods to study road-user behavior and types of available 

behavioral data. Based on the information from this literature 

review, Romo has since developed a framework to categorize 

behavior data from various sources, such as crash databases, 

driving simulator experiments, field test vehicle studies, and naturalistic driving studies. Romo’s research will show the benefit of 

using information from multiple data sources to study behavioral 

issues instead of relying on just one data source.

IMPACT: This research project is expected to demonstrate one 

or more methods of using data from various sources to better 

understand road-user behavior. The concept of combining and 

using behavioral data from multiple sources is relatively new, 

and this work will pave the way for others to follow. Results from 

this project will clearly show many benefits of combining data to 

better understand behavior issues. Integration of human behavior 

collected using different methods could lead to faster design 

and testing of safety countermeasures and new geometric 

designs, resulting in fewer crashes and potentially saved lives. 

The integration of different human behavior data also could provide 

safe and effective methods for studying and testing emerging 

connected-vehicle and automation technologies.

ONGOING RESEARCH: The second year of Romo’s research will 

concentrate on demonstrating applicability of fusing data from 

sources, such as driving simulator experiments and naturalistic 

driving studies, to gain an indepth understanding about certain 

behaviors.

RESOURCES: Several publications resulted from this RAP research. They are outlined below.

Romo, A., Mejia, B., & Yang, C. Y. D. (2014). Utilizing various data sources 

for surface transportation human factors research: workshop 

summary report (Publication No. FHWA-HRT-14-077). FHWA Turner–

Fairbank Highway Research Center, McLean, VA. View the report at 

http://www.fhwa.dot.gov/advancedresearch/pubs/14077/index.cfm.

Romo, A., Yang, C. Y. D. (2015). The science and art of putting drivers under 

the microscope. Public Roads, 78(5). Federal Highway Administration 

Pub. No. FHWA-HRT-15-003.

The relationship between research methods and impacting factors. 

Note: There are five empirical factors that can be used to evaluate the quality 

of data and the analysis performed. The five factors are: driving states, risk, level 

of control, measurements, and validity. The five factors presented in this figure 

explain the similarities, differences, advantages, and disadvantages among the 

different research methods.

Human Behavior and Travel Choices
EAR PROGRAM—RESEARCH ASSOCIATES PROGRAM|9

Human Behavior and Travel Choices

PROJECT: Operational and Safety Analyses of Alternative Intersection/Interchange Designs

ASSOCIATE: Nopadon Kronprasert

SCHOOL: Virginia Polytechnic Institute and State University

PERIOD: November 2012–April 2014

OBJECTIVE: To evaluate operational and safety impacts when implementing alternative intersection and interchange designs. 

ADVISER: Wei Zhang, FHWA Office of Safety Research and Development

SUMMARY: Transportation and traffic professionals working on 

today’s highway improvement projects face daunting pressures 

from the needs of different stakeholders to provide safe, efficient, 

and cost-effective intersections and interchanges. FHWA recently 

proposed several alternative intersection and interchange designs 

to improve the safety- and mobility-related issues across the 

Nation. These new intersections and interchanges include displaced left-turn, median U-turn, and restricted-crossing U-turn 

intersections, as well as the double-crossover diamond interchange. It is important to evaluate how efficient the new designs 

will be and to identify the traffic conditions that will deliver the 

best cost–benefit performance. In accordance with this objective, 

Nopadon Kronprasert’s research project investigated operational 

and safety measures and evaluation procedures, analyzed proposed designs at different evaluation sites, and developed mathematical models for evaluating operational and safety measures 

for different intersection and interchange designs. Kronprasert 

used microscopic traffic simulation to model characteristics and 

behaviors of traffic systems and to evaluate the performance of 

alternative designs. This is a cost-effective method to compare 

different designs, predict potential impacts, replicate real-world 

phenomena, and provide valuable insights into the effects on 

operational and safety performance. Kronprasert conducted his 

research based on problems derived from real projects. As part of 

the technical support to State departments of transportation, he 

performed traffic simulation studies of three double-crossover 

diamond interchanges, three restricted-crossing U-turn intersections, and six miniroundabout projects.

IMPACT: As of October 2014, at least one restricted-crossing 

U-turn and three miniroundabouts Kronprasert worked on have 

been constructed and opened to traffic. Many of the performance 

predictions stated in his research are being verified in the field. 

The results will help analysts understand the relationships between 

A screen capture of an intersection based on Nopadon Kronprasert’s 

simulation input.
10|EAR PROGRAM —RESEARCH ASSOCIATES PROGRAM

Human Behavior and Travel Choices

A screen capture of the simulation video created by Nopadon Kronprasert.

the features of alternative designs and their operational and safety benefits. The research will ultimately help practitioners to find the best course of 

action when implementing alternate designs and 

also will help highway engineers and the public 

understand the benefits and impacts.

ONGOING RESEARCH: Wei Zhang is continuing to 

conduct research on alternative intersection and 

interchange designs, building on Kronprasert’s 

work. Zhang and Kronprasert are also collaborating 

on at least two more research papers.

RESOURCES: Several publications and papers resulted from this RAP research. They are outlined below.

Krause, C., Kronpraset, N., Bared, J., & Zhang, W. (2015). Operational 

advantages of dynamic reversible left-lane control of existing signalized 

diamond interchanges. Journal of Transportation Engineering, 141(5).

Zhang, W., & Kronprasert, N. (2014). The ABCs of Designing RCUTs. Public 

Roads, 78(2), 9–13.

Zhang, W., & Kronprasert, N. (2014). Unlock DDI’s capacity potential by 

implementing relaxed bowtie, superstreet, and quadrant road design at 

adjacent signal intersections. Presented at the Second International 

Conference on Access Management, Shanghai, China.

Zhang, W., & Kronprasert, N. (2014). Unlock diverging diamond interchange’s 

capacity potential using relaxed bowtie design at adjacent signalized 

intersection. Presented at the Transportation Research Board’s Alternative 

Intersections and Interchanges Symposium, Salt Lake City, UT.

Zhang, W., & Kronprasert, N. (2014). Crash prediction models for rural 

restricted crossing U-turn intersections. Presented at the Transportation 

Research Board’s Alternative Intersections and Interchanges Symposium, 

Salt Lake City, UT. 

Zhang, W., & Kronprasert, N. (2014). Mini-roundabout case studies. Presented 

at the Transportation Research Board’s International Roundabout 

Conference, Seattle, WA.

Zhang, W., Kronprasert, N., & Gustafson, J. (2014). Unclog local network 

congestion using high-capacity mini-roundabouts: A feasibility study. 

Presented at the Transportation Research Board’s 93rd Annual Meeting, 

Washington, DC.

Lochrane, T., Kronprasert, N., Bared, J., Dailey, D., & Zhang, W. (2014). 

Determination of mini-roundabout capacity in the United States. 

Journal of Transportation Engineering, 140(10).

Zhang, W., & Kronprasert, N. (2013). Restricted crossing U-turn intersection 

design for improving safety and mobility at high-speed stop-controlled 

intersections. Presented at the Road Safety and Simulation International 

Conference, Rome, Italy.

Zhang, W., Kronprasert, N., & Bared, J. G. (2013). Visualizing the benefits of 

restricted crossing U-turn intersection design at high-speed two-way 

stop-controlled intersections. Presented at the Transportation Research 

Board’s Seventh International Visualization in Transportation Symposium, 

Irvine, CA.
EAR PROGRAM—RESEARCH ASSOCIATES PROGRAM|11

PROJECT: Utilizing Naturalistic Driving Data and Highway Safety Information System to Advance Highway 

Crash Data Modeling Concepts and Methods

ASSOCIATE: Kun-Feng Wu

SCHOOL: Pennsylvania State University

PERIOD: July 2012–June 2013 

OBJECTIVE: To advance safety analysis using surrogate safety measures and improve the evaluation of 

intervention effectiveness. 

ADVISER: Craig P. Thor, FHWA Office of Safety Research and Development

SUMMARY: Kun-Feng Wu’s research project builds on 40 years of 

research concerning the development of crash surrogates for 

assessing traffic safety. The term crash surrogate refers to a crash 

or near-crash event, defined in this project by a set of driver or 

event attributes, driving environment, and kinematic variables. 

Researchers use crash surrogates because crashes are rare events, 

making it hard to draw statistically valid conclusions about contributing factors. Surrogate event counts can be used to predict the 

expected number of crashes and identify sites with promise for 

improvement by knowing the number of surrogate events at each 

intersection. Wu investigated a sequence of statistical tests with 

the overall goal of validating surrogate events and facilitating their 

use in enhanced safety analyses. Wu used raw naturalistic driving 

data, including vehicle kinematic, video, and location information, 

to produce sets of specific conditions that identify crashes and 

near crashes (i.e., surrogate events). Wu tested the procedure on 

a small, 100-car naturalistic driving study dataset, conducted by 

the Virginia Tech Transportation Institute, with successful results. 

A second validation procedure compared these results with the 

number of crashes observed in HSIS data, a multistate database 

that contains crash, roadway inventory, and traffic volume data 

for a select group of States. Wu’s research extends research 

already completed in the joint use of crash events and surrogate 

events in a structured framework. His research project specifically 

compared surrogate analyses of countermeasure effectiveness 

and sites with improvement potential to comparable HSIS studies. 

Wu applied the same methods to evaluate the Integrated VehicleBased Safety System dataset (an initiative designed to develop 

and field test an integrated safety system on light vehicles 

and commercial trucks). In addition, Wu expanded the procedures 

to include diagnostic analytical techniques borrowed from 

medical science. These statistical methods allow for a more 

accurate assessment of the presence of surrogate events.

IMPACT: Specific conditions for defining surrogate events could be 

further tested and studied through driving performance assessment and may ultimately lead to improved understanding of inappropriate driving behaviors, driver responses, roadway design, and 

operational deficiencies. In addition, crash surrogate studies could 

ultimately reduce the time needed to develop a sufficient sample 

size for analysis. These studies would enable researchers to develop models with greater prediction precision and understand 

the factors that contribute to crashes. Decreasing the time and 

increasing the precision of factors that contribute to crashes allow 

faster development and implementation of better countermeasures, thereby reducing crashes and potentially saving lives.

RESOURCES: The papers that resulted from this RAP research are 

outlined below.

Wu, K. F., Thor, C., & Ardiansyah, M. N. (2016). Identify sequence of events 

likely to result in severe crash outcomes. Accident; Analysis and Prevention, 96:198-207.

Wu, K. F., & Thor, C. (2015). Method for the use of naturalistic driving study 

data to analyze rear-end crash sequences. Transportation Research 

Record, Journal of the Transportation Research Board, 2518(2518):27-

36.

A schematic that relates the crash progression process to the etiological process 

of disease progression. 

The crash symptoms (horizontal lines) as they compare to manual identification 

of a crash-related event (vertical red lines). This exhibits the potential of 

surrogate measures to predict safety-related events based on kinematic and 

environmental factors.

Safety-related

Event

Surrogate Event/

Crash Symptom

Disease

Begins

Induction Promotion Expression

Start of

Etiology Process

Clinical

Symptoms

Outcome of

Disease

Near Crash

Crash

© Kun-Feng Wu

-100

Symp. A

Measurement Duration (Unit 0.1 Seconds)

Symp. D Symp. E Symp. F Symp. B

-50 0 50 100 150 200

Case 23 (Crash=0) Case 34 (Crash=1)

Case 49 (Crash=0) Case 52 (Crash=0)

-100

Symp. A

Measurement Duration (Unit 0.1 Seconds)

Symp. D Symp. E Symp. F Symp. B

-50 0 50 100 150 200

-100

Symp. A

Measurement Duration (Unit 0.1 Seconds)

Symp. D Symp. E Symp. F Symp. B

-50 0 50 100 150 200 -100

Symp. A

Measurement Duration (Unit 0.1 Seconds)

Symp. D Symp. E Symp. F Symp. B

-50 0 50 100 150 200

© Kun-Feng Wu

Human Behavior and Travel Choices
12|EAR PROGRAM —RESEARCH ASSOCIATES PROGRAM

Technology for Assessing Performance

PROJECT: Developing Frameworks of Performance-Based Asphalt Mix Design

ASSOCIATE: Jong-Sub Lee

SCHOOL: North Carolina State University

PERIOD: September 2015–April 2016

OBJECTIVE: To investigate use of mechanistic models to evaluate voids in mineral aggregate (VMA), design air void content, and 

in-place air void content as parameters for reliably predicting field performance of various asphalt mix designs.

ADVISER: Katherine Petros, FHWA Office of Infrastructure Research and Development

SUMMARY: Performance-related specifications (PRS) will offer 

engineers, contractors, and funding agencies a way to assess 

future performance, maintenance requirements, and lifecycle 

costs for highway construction projects. PRS can be thought 

of as a set of quality assurance specifications that describe the 

desired levels of key materials and construction-acceptance 

quality characteristics that correlate with fundamental 

engineering properties that predict performance. PRS will rely 

on models that objectively assess performance based on 

observed construction-quality characteristics related to 

fundamental engineering properties and will:

• Utilize testing that focuses on key measureable characteristics 

related to performance.

• Use pavement design assumptions as a basis for construction 

performance.

• Incorporate incentives and disincentives based on modeled 

performance.

• Allow contractors to innovate and be competitive.

• Reduce long-term monitoring and management.

When fully developed, PRS will employ the quantified 

relationships containing the characteristics to predict asconstructed pavement performance. Thus, PRS will provide 

the basis for rational acceptance and pay-adjustment decisions 

related to highway construction projects.

Jong-Sub Lee’s research helped develop a testing and 

modeling framework for performance-based asphalt mix 

design. The goal was to identify the effect of volumetric mix 

design targets (design VMA and design air void) and 

compaction level (in-place air density) on fatigue 

characteristics and performance. The project investigated 

asphalt mixtures based on the Superpave® mix design system 

(developed through the Strategic Highway Research Program) 

using mechanistic analyses based on the viscoelastic 

continuum damage (VECD) analyses and mechanistic–

empirical pavement analysis using the AASHTOWare Pavement 

ME Design® program. The analyses included the simplified 

VECD model at the material level and two structural models: 

(a) layered viscoelastic analysis and (b) layered viscoelastic 

pavement analysis for critical distresses.

Key performance-related findings of the research include:

• The damage state at failure is increased (i.e., better fatigue 

performance) with an increase in the design VMA and a 

decrease in the in-place air void and design air void content. 

The design VMA is more sensitive than the others.

• Fatigue life was found to improve when the value of the design

VMA was increased and the in-place air void content and 

design air void content was decreased in rank of sensitivity.

• Superpave® mix design parameter of design VMA was the 

most sensitive parameter that significantly affected the 

linear viscoelastic property, damage characteristic, and 

fatigue life in the mechanistic analysis. 

• The effect of the design air void on mechanistic fatigue life 

was diminished as the pavement thickness increased.

• Increasing the design VMA content caused the least amount 

of fatigue cracking area at the thin pavement.

IMPACT: Data gathered through this research will contribute to 

the development of testing and modeling protocols that can be 

used to develop PRS for asphalt mix design.

RESOURCES: The following reports resulted from this RAP research 

and are outlined below.

Lee, J-S., Kim, Y. (2014). Performance-based moisture susceptibility 

evaluation of warm-mix asphalt concrete through laboratory tests. 

Transportation Research Record, Journal of the Transportation Research 

Board, 2446.

Lee, J., Norouzi, A., and Kim, Y. R. (2016). Determining specimen geometry 

of cylindrical specimens for direct tension fatigue testing of asphalt 

concrete. Journal of Testing and Evaluation, 45(2).

Lee, J-S., Gibson, N., Kim, Y. R. (2015). Use of mechanistic models to investigate 

fatigue performance of asphalt mixtures: effects of asphalt mix design 

targets and compaction. Transportation Research Record, Journal of the 

Transportation Research Board, 2507.

Performance Specifications for Rapid Renewal (R07). AASHTO Strategic 

Highway Research Program at http://shrp2.transportation.org/Pages/

R07 PerformanceSpecificationsforRapidRenewal.aspx

Balis, J., & Platte, K. (n.d.). Performance specifications to speed construction, 

reduce oversight, and encourage innovative approaches: Performance 

specifications for rapid renewal (R07). SHRP2 Solutions.

The following Web site provides insight on the FHWA UHPC research portfolio: 

https://www.fhwa.dot.gov/construction/ pssr0402.cfm
EAR PROGRAM—RESEARCH ASSOCIATES PROGRAM|13

Technology for Assessing Performance

PROJECT: Developing and Implementing Dynamic Junction Control System in the United States

ASSOCIATE: Ximiao Jiang

SCHOOL: University of Tennessee, Knoxville

PERIOD: October 2013–May 2015 

OBJECTIVE: To investigate the efficiency of dynamic merge control (DMC) strategy at freeway merge areas. 

ADVISER: Joe Bared, FHWA Office of Operations Research and Development

SUMMARY: Dynamic merge control (DMC) is a traffic management 

strategy that can be used to dynamically monitor and control traffic flow at freeway on- or off-ramps or where multiple-lane freeways merge—for example, where a 2-lane freeway merges with a 

3-lane freeway into 4 lanes. DMC minimizes disruption that can 

occur, for example, when traffic volume on an on-ramp is significantly higher than on the freeway. In this case, ramp traffic must 

find gaps in lower volume freeway traffic, resulting in hesitation 

and delay and increasing the possibility of rear-end collisions. 

DMC strategy, now being used in Germany and the Netherlands, 

assigns priority to the high-volume traffic stream. In the example 

above, DMC could close the right lane of the main freeway and allow ramp traffic free access at the merge. DMC has not been implemented anywhere in the United States, and knowledge of the 

strategy is still experimental here.

Ximiao Jiang’s research project used an analytical technique called 

microsimulation to examine the effectiveness of DMC on several 

road and traffic configurations. Microsimulation can effectively 

model the behavior of many individual vehicles within specified 

traffic environments, including merge queuing and congested 

road networks, to the point of gridlock. Dr. Jiang simulated DMC 

lane-closing strategy on two traffic configurations: the first, two 

2-lane freeways merging into 3 lanes, and the second, a 3-lane 

freeway merging with a 2-lane freeway into 4 lanes. Simulations 

included traffic demands ranging from 1,000 vehicles per hour 

(vph) to 4,600 vph on 3 lanes and 2,500 vph to 6,500 vph on 2 

lanes. In the simulations, signals notify drivers of lane closure 2,500 

ft upstream of the lane closing and close the lane 1,000 ft upstream of the merge. The simulation assumed that drivers would 

be 100-percent compliant with lane closure. Fifteen runs were simulated for each scenario. Key findings of the simulations are:

• Implementing DMC strategy produced benefits in vehicle delay 

and speed at almost all demand combinations. 

• When traffic demand on the minor roadway reached 1,900

vph per lane, DMC benefits became statistically and practically 

significant.

• DMC reduced lane changing in the merge area, thereby

increasing capacity and delaying the formation of bottlenecks.

IMPACT: This research represents an important first step in evaluating the DMC strategy as an effective approach to reducing delays 

and congestion at freeway merge areas.

ONGOING RESEARCH: The next phase of DMC microsimulation will 

investigate varying closing locations and varying distances at 

which drivers are warned. The next phase also will investigate various closed-lane compliance ratios.

RESOURCES: Several publications resulted from this RAP research. 

They are outlined below.

Jiang, X., Gan, Q., Bared, J., Mannes, M., & Hale, D. (2015). Traffic performance analysis of dy namic merge control using micro-simulation. 

Transportation Research Record, Journal of the Transportation Re search 

Board, 2484.

Zhang, Y., Jiang, X., Haghani, A., & Huang, B. (2015). Exploring nonlinear 

effects of traffic crash determinants using a novel poisson-mixed multivariate adaptive regression splines model. Transportation Research Record, Journal of the Transportation Research Board, 2515.

Microsimulation studies evaluated 

dynamic merge control in configurations such as a 2-lane freeway 

merging with a 3-lane freeway to 

form four traffic lanes.

From Jiang, X., J. Bared, M. Maness, 

and D. Hale. Traffic Performance 

Analysis of Dynamic Merge Control 

Using Microsimulation. Transportation Research Record: Journal of 

the Transportation Research Board, 

No. 2484, Figure 1, p. 24, 2015. 

Reproduced with permission of the 

Transportation Research Board.
14|EAR PROGRAM —RESEARCH ASSOCIATES PROGRAM

Technology for Assessing Performance

PROJECT: Tensile Response of Ultra-High Performance Concrete: Validation of Characterization Methods

ASSOCIATE: Luis Felipe Maya Duque

SCHOOL: Polytechnic University of Madrid

PERIOD: June 2013–April 2016

OBJECTIVE: To critically assess the applicability of a recently proposed tensile-test method for ultra-high performance, 

fiber-reinforced concrete. 

ADVISER: Ben Graybeal, FHWA Office of Infrastructure Research and Development

SUMMARY: Concrete is the most widely used construction material 

and has played a fundamental role in the development of infrastructure since the Romans. Advances in fiber-reinforced concretes over the last 50 years have enabled the development of an 

entirely new generation of cement-based composite materials. 

Ultra-high performance concrete (UHPC) represents a class of cement composites with high compressive strength and whose tensile response is characterized by high-strain capacity accompanied by multiple microcracking. To take full advantage of the tensile behavior of these UHPC materials, it is necessary to develop 

tensile-test methods and guidelines to be incorporated into codes 

and recommendations. Luis Felipe Maya Duque’s research project 

focused on the assessment of proposed test methods designed to 

provide a reliable assessment of UHPC tensile behavior, not only 

in a research environment, but also for quality-control purposes in 

a production environment. Maya Duque assessed a singular direct 

tensile-test method that has already been the subject of FHWA 

research to establish advantages and drawbacks compared with 

existing methods. Maya Duque also conducted a critical review of 

the state of the art in tensile-test methods for UHPC. The research 

project included an extensive experimental campaign to properly 

assess the performance of the proposed tensile-test method. 

Furthermore, Maya Duque also considered the suitability of the 

direct tension test method to accurately reflect the influence of 

the fiber distribution and orientation in structural elements.

IMPACT: This research allows for the development and implementation of a quality control test method for UHPC in a production 

environment. Broader use of UHPC could lead to more durable 

and longer lasting highway structures, reducing the cost and 

risks associated with reconstruction.

ONGOING RESEARCH: FHWA conducted over 120 direct tension 

tests on both mold-cast and sawed specimens to assess the 

influence of flow conditions, as well as fiber orientation and fiber 

distribution on the tensile response of UHPC. FHWA also performed flexural tests on UHPC strips and slabs to correlate the 

results from the material characterization tests with the mechanical response of structural elements. Those results will contribute 

to assessing the reliability of the current design approaches as 

well as to improving understanding of the main mechanisms and 

variables to be considered in the development of design codes 

and recommendations. Maya Duque continues to complete the 

assessment of the structural efficiency of fiber reinforcement in 

UHPC structures through an experimental and analytical validation process at FHWA. FHWA plans to conduct two full-scale 

beam tests at the TFHRC Structures Laboratory. The results of 

these tests will provide insight for the development of continuity 

connection using UHPC as an alternative to increase the span 

range currently covered by conventional, precast, prestressed 

concrete girders.

RESOURCES: Several publications and papers resulted from this 

RAP research. They are outlined below.

Maya, L. F., Zanuy, C., Albajar, L., Lopez, C., & Portabella, J. (2013). 

Experimental assessment of connections for precast concrete frames 

using ultra high performance fibre reinforced concrete. Construction 

and Building Materials, 48(11), 173–186.

Maya, L. F., Ruiz, M., Muttonni, A., & Foster, S. J. (2012). Punching shear 

strength of steel fibre reinforced concrete slabs. Engineering Structures, 40, 83–94.

Graybeal, B., & Baby, F. (2013). Development of a direct tension test method for ultra-high-performance fiber-reinforced concrete. ACI Materials 

Journal, 110(2) 177–186.

The following Web site provides insight on the FHWA UHPC research portfolio: 

http://www.fhwa.dot.gov/research/resources/uhpc/

Casting of beam splice 

connection.

Full-scale flexural test of 

a beam splice connection 

made of UHPC.
EAR PROGRAM—RESEARCH ASSOCIATES PROGRAM|15

PROJECT: Prediction of Pavement Temperature Profiles Using Surface Temperatures: An Analytical Approach With 

Model Validation Based on Long-Term Pavement Performance Data

ASSOCIATE: Dong Wang

SCHOOL: University of Illinois at Urbana–Champaign

PERIOD: June 2011–May 2013

OBJECTIVE: To derive and field-validate an easily implementable algorithm for predicting temperature profiles in paving materials. 

ADVISER: Yan “Jane” Jiang, FHWA Office of Infrastructure Research and Development

SUMMARY: The mechanical properties of paving materials are 

usually temperature-dependent, but to accurately back-calculate 

the elastic moduli of pavement layers (i.e., the pavement’s resistance to being deformed elastically when a force is applied to it), 

time-dependent pavement temperature must be known. Knowing 

the temperature profile allows researchers to better characterize 

the properties of paving materials and predict pavement responses 

under traffic and environmental loadings. Dong Wang’s research 

project investigated a new method for predicting time-dependent 

pavement temperature profiles with limited inputs. There are currently three main methods for predicting temperature profiles: 

statistics-based models, numerical, and analytical approaches. 

These existing methods require large databases of climatic, meteorological, and geographical data and several other inputs to 

predict temperatures for the algorithms to operate effectively. 

Current pavement-testing methods do not easily obtain the 

required climatic data; thus, these algorithms are subsequently 

limited in their ability to predict pavement temperature profiles. 

Wang focused his research effort on infrared pavement surface 

temperature data that can be easily obtained during pavement 

testing. This improved approach makes it possible to develop an 

entirely new algorithm for predicting a time-dependent pavement 

temperature profile that requires very limited inputs when compared with previous algorithms. The only inputs needed for this 

new method are infrared surface temperatures, initial pavement 

temperature profile, pavement geometry, and thermal properties 

of layer materials. Most important, unlike previous methods, no 

climatic data are required. To validate the new algorithm, when 

there are so many different types of pavement structures across 

regions with varied climatic conditions, an extremely large temperature dataset is required. To meet this requirement, Wang used 

data from the Long-Term Pavement Performance (LTPP) Program 

database for model validation.

IMPACT: Wang’s research is expected to greatly benefit field 

engineers in characterizing pavement temperature for the purpose 

of analyzing and interpreting testing data. In addition, it could 

lead to high savings on pavement evaluation costs.

RESOURCES: Several publications and papers resulted from this 

RAP research. They are outlined in the following column.

Wang, D. (2013). Prediction of asphalt pavement temperature profile 

during FWD testing: A simplified analytical solution with model 

validation based on LTPP data. Journal of Transportation Engineering, 

139(1), 109–113.

Wang, D. (2012). Analytical approach to predict temperature profile in a 

multilayered pavement system based on measured surface temperature 

data. Journal of Transportation Engineering, 138(5), 674–679.

Wang, D. (2013). Simplified analytical approach to predict asphalt pavement temperature. Journal of Materials in Civil Engineering, 27(12).

Wang, D. (2013). Prediction of asphalt pavement temperature profile 

during FWD testing: simplified analytical solution with model validation based on LTPP data. Journal of Transportation Engineering, 139(1).

Wang, D. (2012, July 5–7). Prediction of time-dependent temperature profile in a slab. Paper presented at the Third Advanced Workshop on 

Innovations and Modeling for Sustainable and Resilient Concrete Pavements, Quebec, Canada.

Wang, D. (2013, January 13–17). Assessing BELLS3 equation in predicting 

asphalt layer temperature profile based on the latest LTPP FWD 

temperature data. Paper presented at the 92nd Transportation 

Research Board Annual Meeting, Washington, DC.

Wang, D. (2013, January 13–17). Simplified analytical approach to predict 

temperature profile within a PCC slab during FWD testing. Paper 

presented at the 92nd Transportation Research Board Annual Meeting, 

Washington, DC.

Wang, D. (2012, January 22–26). Model validation based on LTPP data to 

predict asphalt temperature profile. Paper presented at the 91st 

Transportation Research Board Annual Meeting, Washington, DC. 

Wang, D. (2012, January 22–26). Prediction of temperature profile in a 

multilayered pavement system using measured surface temperature 

data: An analytical approach. Paper presented at the 91st Transportation 

Research Board Annual Meeting, Washington, DC.

Histogram of asphalt pavement subsurface temperature difference 

(predicted (Tp

)-measured (Tm) temperature difference).

© Dong Wang 

Technology for Assessing Performance
16|EAR PROGRAM —RESEARCH ASSOCIATES PROGRAM
EAR PROGRAM—RESEARCH ASSOCIATES PROGRAM|17

Getting Involved with the EAR Program

To take advantage of a broad variety of scientific and engineering discoveries, the EAR 

Program involves both traditional stakeholders (State department of transportation 

researchers, University Transportation Center researchers, and Transportation Research 

Board committee and panel members) and nontraditional stakeholders (investigators from 

private industry, related disciplines in academia, and research programs in other 

countries) throughout the research process.

Learn More

For more information, see the EAR Program Web site at www.fhwa.dot.gov/advanced 

research. The site features information on research solicitations, updates on ongoing 

research, links to published materials, summaries of past EAR Program events, and 

details on upcoming events.
18|EAR PROGRAM —RESEARCH ASSOCIATES PROGRAM

FHWA-HRT-17-023

HRTM-30/02-17(1M)E

EAR Program Results

The EAR Program strives to develop partnerships with the public and private 

sectors because the very nature of the EAR Program is to apply ideas across 

traditional fields of research and stimulate new approaches to problemsolving. 

The program bridges basic research (e.g., academic work funded by National 

Science Foundation grants) and applied research (e.g., studies funded by State 

departments of transportation). In addition to sponsoring EAR Program projects that advance the development of highway infrastructure and operations, 

the EAR Program is committed to promoting cross-fertilization with other 

technical fields, furthering promising lines of research, and deepening vital research capacity.