Project Details
12/01/14
11/30/17
Federal Highway Administration
National Center for Rural Road Safety
Researchers
Nicole Oneyear
About the research
The reduction of severe injury and fatal vehicle crashes within the US requires the involvement of transportation professionals from local, state, and federal agencies. Therefore, a need exists to
increase the transportation safety knowledge base at all levels of government. However, the majority of the roadway miles in the US are under local government jurisdiction.
While the wide range of safety knowledge within these local agencies is generally recognized, in many cases, safety is just one of many areas of responsibility for transportation staff within local roadway agencies. Furthermore, rural road maintenance plays a role in safety for roadway users who travel regularly on our secondary roadways.
This project is in response to a proposal that the compilation and summary of information useful to the development of a rural road safety recognition program for local maintenance personnel would be of value to local agency professional development entities (e.g., Local and Tribal Technical Assistance Programs [LTAPs and TTAPs], local road agencies, and state Departments of
Transportation [DOTs]). This information might include the identification of roadway safety learning objectives and subject areas that could be included within a curriculum of instruction, courses that are currently available, and a process of recognition for local maintenance personnel who complete this curriculum.
The implementation of this type of program for local agency maintenance personnel should encourage a greater safety culture and hopefully help lead to severe injury and fatal vehicle crash reductions along rural roadways within the US.
This report provides a summary of information for those considering the implementation of roadway safety curriculum and/or recognition programs for local agency maintenance personnel.
Project Details
09/03/11
09/02/17
Federal Highway Administration
Researchers
About the research
A continuing challenge to the concrete paving industry is the ever present need to implement new technologies as they are proven, coupled with the need to educate new employees throughout the industry about best practices. The objective of this project was to help meet this need by conducting technology transfer, delivery, and implementation of best practices for jointed concrete pavements. Activities were focused on these topics:
- Material-related distress
- Blended aggregates for concrete mixture optimization
- Concrete paving mixtures with one or more supplementary cementitious materials
- Innovative materials and methods for accelerated construction and maintenance of concrete pavements
- Quality assurance
Project Details
08/17/12
12/05/19
Federal Highway Administration
Researchers
James E. Alleman
Michael Heitzman
About the research
Five portland cement concrete (PCC) and five asphalt concrete (AC) pavement locations at each of seven field testing sites in the central and eastern United States represented a range of aggregate types, pavement surface ages, and climates. Albedo, thermal properties, and pavement surface characteristics data were collected, and cores were obtained to measure thermal properties in the laboratory. Test tracks at Auburn University’s National Center for Asphalt Technology (NCAT) and Minnesota’s MnROAD facility were used to collect 24-hour measurements for thermal model validation.
The albedo data showed that different parameters influence albedo for AC and PCC pavements, albedo approaches a steady value over time, and the albedo trends for each site differ. The AC albedo model reasonably predicted albedo over time using pavement age and coarse aggregate color. However, the PCC albedo model did not predict field albedo using pavement age, coarse aggregate color, and surface texture; additional field study is needed. Climate-related factors, particularly winter maintenance activities, may also play a role in pavement albedo.
Pavement thermal modeling required an understanding of the surface and thermal properties, small incremental units of time and layer thicknesses, 10 to 20 days of simulation to achieve balance throughout the pavement and subgrade system, and continuous data over an extended period. The thermal model predicted pavement thermal response in warm, dry conditions but did not account for the influence of moisture and freezing conditions.
Asphalt and concrete thermal properties vary and may have up to a 15% influence on AASHTOWare Pavement ME Design results. Current highway sustainability rating systems have recognized the complexity of pavement albedo, and the current systems either only address qualitative cool pavement goals or have no coverage of albedo-related metrics or outcomes.
Researchers
Peter Savolainen
John Lee
About the research
Safe intersection negotiation depends on drivers being able to recognize the presence of an intersection and then respond appropriately to applicable traffic control devices and prevailing conditions. When drivers are required to yield right-of-way to on-coming traffic, they also need to be able to identify and select appropriate gaps. Consequently, the proposed research for Phase I investigates the feasibility of answering the following research questions, which address the relationship between different stages of intersection negotiation and roadway and driver characteristics.
- What is the relationship between rural intersection crash risk and driver, roadway, and environmental characteristics?
- What is the relationship between intersection recognition and stopping behavior and intersection geometry and countermeasures?
- What are the primary influences for appropriate scanning behavior and gap acceptance at rural intersections?
Researchers
About the research
This multi-phase study utilized Second Strategic Highway Research Program (SHRP2) Naturalistic Driving Study (NDS) data to evaluate the impact of traffic control devices in reducing driver speed in work zones. The main advantage to the SHPR2 NDS data is that on-road driver behavior was captured and can be used to evaluate how drivers behave in various situations. The study included four different analyses. The first evaluated where drivers began reacting to various work zone traffic control devices. The second assessed how drivers changed speed upstream to immediately downstream as they encountered various traffic control devices. The third assessed how drivers react when they encounter the back of a queue and the fourth developed speed based on work zone characteristics such as presence of barriers.
The project also includes a toolbox that summarizes information about work zone traffic control devices, countermeasures, and work zone features that have a demonstrated impact on speed in work zones. Features were identified through a survey of the literature. Additional information for some of the features and countermeasures was gained through the various analyses of SHRP2 data conducted through this project. Guidance from the work zone traffic control manuals for various states was summarized when appropriate. Recommendations for use of each feature or countermeasure relevant to addressing speed in work zones was developed by the team and reviewed by work zone experts and the project panel.
Project Details
06/15/16
08/31/16
Federal Highway Administration
Iowa Department of Transportation
Researchers
About the research
This work supported drafting project management guidance for the Iowa Department of Transportation (DOT). The goal is to incorporate a greater focus on project management in their project development process.
A technical advisory committee (TAC) was assembled to accomplish this effort. The TAC took into consideration the current status of project management with the Iowa DOT, their experience during the demonstration workshop held in Iowa as part of the implementation assistance they received, the project management peer exchange hosted by the Iowa DOT, and additional examples of project management that were presented. With this basis, the TAC participated in a number of discussions to develop draft guidance for the foundation of a Project Management Office (PMO) within the Iowa DOT.
The final report describes the process that was used in establishing this guidance. The report details the decisions and decision process that the TAC employed in this endeavor and provides additional thoughts and insight into the draft guidance. Appendix A includes the draft guidance in the form of PMO function details and detailed lists of project management roles and responsibilities. Appendix B includes a starter list of project management resources for the PMO.
Researchers
About the research
The objective of this task is to provide for technical analysis to support the bridge condition performance measure rulemaking effort.
Researchers
About the research
Although chevron alignment signs have been utilized for some time along horizontal curves, their effectiveness is not well documented. The Crash Modification Factors Clearinghouse includes crash modification factors (CMFs) for chevrons from 0.41 to 1.92 (FHWA 2015).
The lack of documentation on the effectiveness of chevrons and the range of values for CMFs make it difficult for agencies to estimate the cost effectiveness of chevrons. As a result, the objective of this study was to develop a CMF for chevron alignment signs that can be used by Iowa agencies to help address crashes on curves.
Funding Sources:
Federal Highway Administration TSF Funding
Iowa Department of Transportation
Midwest Transportation Center
USDOT/OST-R
Contract Number: DTRT13-G-UTC37
Researchers
Doug Gransberg
Hyung Seok "David" Jeong
Gary Stanton
About the research
The objective of this research is to develop a guidebook, for use by departments of transportation (DOTs) and other agencies, on estimating transportation project preconstruction services costs. The guidebook is meant to be suitable for formal balloting and acceptance by the American Association of State Highway and Transportation Officials (AASHTO) Subcommittee on Design through the Technical Committee on Preconstruction Engineering Management and for maintenance and updating by these or other AASHTO groups.
Researchers
About the research
Rumble strips are a low cost safety countermeasure used to reduce roadway/lane departure crashes. When a pavement marking is applied over the rumble pattern, it is known as a rumble stripe. The practices from state to state are not uniform and there may not be one ideal design for all applications. There are advantages and disadvantages to the different rumble designs. This synthesis will identify current practices used by states installing rumble strips and rumble stripes. The scope of this synthesis study will focus on the safety benefits, rumble design, external noise considerations, durability/maintenance issues, impacts on bicyclists, and public affairs/outreach efforts. Results will benefit government agencies, researchers, and the road-building industry in providing guidance on successful practices. This synthesis will include a literature review and a survey of state departments of transportation (DOTs) and Canadian ministries of transportation. International agencies’ experience will be reviewed as available. From the results of the survey, a minimum of three agencies will be selected and case examples of their practices will be shared. Lessons learned and gaps in information will also be covered.
Visit the Transportation Research Board’s project website.