Transportation Research Board
HomeContact Us Directory E-NewsletterFollow Us RSS

The National Academies
Publications > Highway (NCHRP) > Research Results Digests
Text Size: Increase Text SizeDecrease Text Size| Share:



National Cooperative Highway Research Program (NCHRP) Research Results Digests (RRDs)

RRDs are used to promote early awareness of project results in order to encourage implementation. RRDs also summarize specific findings that emphasize how the research may be used. The contents are organized in terms of the problem and the solution to it, the findings, and the applications. RRDs generally run 4–32 printed pages.

Below are the latest 20 NCHRP Research Results Digests that have been produced by TRB.  A page highlighting NCHRP Research Results Digests that have been released since June 2001 is available online.  To search for older publications visit the TRB Online Bookstore or the TRB Publication Index.


 
Guidelines for Project Selection and Materials Sampling, Conditioning, and Testing in WMA Research StudiesGuidelines for Project Selection and Materials Sampling, Conditioning, and Testing in WMA Research Studies
February 29, 2012
TRB’s National Cooperative Highway Research Program (NCHRP) Research Results Digest 370: Guidelines for Project Selection and Materials Sampling, Conditioning, and Testing in WMA Research Studies summarizes a May 2011 workshop designed to help foster cooperation and coordination among warm-mix asphalt (WMA) research studies. The goals of the workshop were to help identify the laboratory and fie...
AASHTO T 209: Effect of Agitation Equipment Type on Theoretical Maximum Specific Gravity ValuesAASHTO T 209: Effect of Agitation Equipment Type on Theoretical Maximum Specific Gravity Values
February 17, 2012
TRB’s National Cooperative Highway Research Program (NCHRP) Research Results Digest 369: AASHTO T 209: Effect of Agitation Equipment Type on Theoretical Maximum Specific Gravity Values evaluates the effect of using various devices and methods on measured values of theoretical maximum specific gravity (Gmm) used to determine the air void content and the in-place density of hot-mix asphalt (HMA) ...
State DOT Financial Auditing Requirements for Public Transportation Assistance ProgramsState DOT Financial Auditing Requirements for Public Transportation Assistance Programs
March 26, 2012
TRB’s National Cooperative Highway Research Program (NCHRP) Research Results Digest 368: State DOT Financial Auditing Requirements for Public Transportation Assistance Programs identifies various financial policies and procedures used by states for conducting grantee financial audits. The report documents policies, procedures, and practices used by some state departments of trans...
Continuing Project to Synthesize Information on Highway Problems: 2012Continuing Project to Synthesize Information on Highway Problems: 2012
February 9, 2012
TRB’s National Cooperative Highway Research Program (NCHRP) Research Results Digest 367: Continuing Project to Synthesize Information on Highway Problems is a digest of the progress and status of NCHRP Project 20-5, “Synthesis of Information Related to Highway Problems.”
Local and State Partnerships with Taxicab CompaniesLocal and State Partnerships with Taxicab Companies
February 6, 2012
TRB’s National Cooperative Highway Research Program (NCHRP) Research Results Digest 366: Local and State Partnerships with Taxicab Companies discusses how states and local governments might promote partnerships with taxicab companies for provision of public transportation. In the context of the report, a “partnership” typically involves some form of contract for service, but also includes less ...
Sustainable Pavement Maintenance PracticesSustainable Pavement Maintenance Practices
January 19, 2012
TRB’s National Cooperative Highway Research Program (NCHRP) Research Results Digest 365: Sustainable Pavement Maintenance Practices highlights the current practice in sustainable pavement maintenance and preservation. The report is designed to help quantify and understand how pavement maintenance and preservation practices minimize environmental impacts. As part of the development of this repor...
Validation of LRFD Metal Loss and Service-Life Strength Reduction Factors for Metal-Reinforced SystemsValidation of LRFD Metal Loss and Service-Life Strength Reduction Factors for Metal-Reinforced Systems
October 11, 2011
TRB’s National Cooperative Highway Research Program (NCHRP) Research Results Digest 364: Validation of LRFD Metal Loss and Service-Life Strength Reduction Factors for Metal-Reinforced Systems summarizes the results of research to further validate some key results of a project that resulted in publication of NCHRP Report 675: LRFD Metal Loss and Service-Life Strength Reduction Factors for Metal-...
Hydroacoustic Impacts on Fish from Pile InstallationHydroacoustic Impacts on Fish from Pile Installation
October 26, 2011
TRB’s National Cooperative Highway Research Program (NCHRP) Research Results Digest 363: Hydroacoustic Impacts on Fish from Pile Installation explores the prediction and mitigation of the negative impacts on fish from underwater sound pressure during pile and casing installation and removal.  Appendices A through H for RRD 363 are available online.
Review of Mexican Experience with the Regulation of Large Commercial Motor VehiclesReview of Mexican Experience with the Regulation of Large Commercial Motor Vehicles
October 28, 2011
TRB’s National Cooperative Highway Research Program (NCHRP) Research Results Digest 362: Review of Mexican Experience with the Regulation of Large Commercial Motor Vehicles reviews and summarizes the Mexican experience with changes in truck size and weight limits. The report also evaluates the potential applicability to size and weight limits in the United States.
State DOT Public Transportation Performance Measures: State of the Practice and Future NeedsState DOT Public Transportation Performance Measures: State of the Practice and Future Needs
October 6, 2011
TRB’s National Cooperative Highway Research Program (NCHRP) RRD 361: State DOT Public Transportation Performance Measures: State of the Practice and Future Needs includes information on performance measures and performance management approaches that may be used by state departments of transportation (DOTs) in relation to public transportation programs.
Rheological Characterization of Flow Table Reference MaterialRheological Characterization of Flow Table Reference Material
July 29, 2011
TRB’s National Cooperative Highway Research Program (NCHRP) 360: Rheological Characterization of Flow Table Reference Material summarizes the key findings of a project that characterized available batches of cement and concrete reference laboratory (CCRL) flow table reference material. The project also explored more efficient, stable, and reproducible methods for future production of the refere...
Models to Support State-Owned Park and Ride Lots and Intermodal FacilitiesModels to Support State-Owned Park and Ride Lots and Intermodal Facilities
January 22, 2012
TRB’s National Cooperative Highway Research Program (NCHRP) Research Results Digest 359: Models to Support State-Owned Park and Ride Lots and Intermodal Facilities addresses the needs and issues associated with state park and ride lots and intermodal commuter facilities and programs. The report identifies deficiencies, best practices, and promising innovations.
Statewide Transit Goal SettingStatewide Transit Goal Setting
August 11, 2011
TRB’s National Cooperative Highway Research Program (NCHRP) Research Results Digest 358: Statewide Transit Goal Setting explores current and best practices in statewide transit goal setting by state departments of transportation.
Test Methods and Specification Criteria for Mineral Filler Used in Hot-Mix AsphaltTest Methods and Specification Criteria for Mineral Filler Used in Hot-Mix Asphalt
July 27, 2011
TRB’s National Cooperative Highway Research Program (NCHRP) Research Results Digest 357: Test Methods and Specification Criteria for Mineral Filler Used in Hot-Mix Asphalt summarizes the key findings of a project that identified test methods for mineral filler that characterize its physical and chemical effects on the performance of mastics and hot-mix asphalt. The project also explored propose...
Analysis of State Rural Intercity Bus Strategies: Requirements for Utilization of S.5311(f) FundingAnalysis of State Rural Intercity Bus Strategies: Requirements for Utilization of S.5311(f) Funding
November 28, 2011
TRB’s National Cooperative Highway Research Program (NCHRP) Research Results Digest 356: Analysis of State Rural Intercity Bus Strategies: Requirements for Utilization of S.5311(f) Funding provides a snapshot of the current status of the program across the nation, and also provides states with examples and recommendations for program implementation. Section 5311(f) funds intercity bus service i...
Summary of Cast-In-Place Concrete Connections for Precast Deck SystemsSummary of Cast-In-Place Concrete Connections for Precast Deck Systems
July 26, 2011
TRB’s National Cooperative Highway Research Program (NCHRP) RRD 355: Summary of Cast-In-Place Concrete Connections for Precast Deck Systems summarizes the results of a project that developed recommended design and construction specifications and examples for the design and construction of durable cast-in-place reinforced concrete connections for precast deck systems. The project focused on syst...
A Review of Human Services Transportation Plans and Grant ProgramsA Review of Human Services Transportation Plans and Grant Programs
September 14, 2011
TRB’s National Cooperative Highway Research Program (NCHRP) Research Results Digest 354: A Review of Human Services Transportation Plans and Grant Programs explores the level of effort and costs associated with the development of coordinated public transit-human services transportation plans. The report also discusses the perceived success of the Coordination Plans and the perceived success sta...
Identification of Local Matching Fund Requirements for State-Administered Federal and Non-Federal Public Transportation ProgramsIdentification of Local Matching Fund Requirements for State-Administered Federal and Non-Federal Public Transportation Programs
June 10, 2011
TRB’s National Cooperative Highway Research Program (NCHRP) Research Results Digest 353: Identification of Local Matching Fund Requirements for State-Administered Federal and Non-Federal Public Transportation Programs documents the policies adopted by the states to provide matching funds for state-administered federal and non-federal public transportation grant programs. The report include...
Cost/Benefit Analysis of Converting a Lane for Bus Rapid Transit—Phase II Evaluation and MethodologyCost/Benefit Analysis of Converting a Lane for Bus Rapid Transit—Phase II Evaluation and Methodology
May 13, 2011
TRB’s National Cooperative Highway Research Program (NCHRP) Research Results Digest 352: Cost/Benefit Analysis of Converting a Lane for Bus Rapid Transit—Phase II Evaluation and Methodology provides transportation agencies with a methodology and a guide for evaluating the potential benefits and costs of converting a mixed-flow lane to exclusive bus rapid transit use.
Precision Statements for AASHTO Standard Methods of Test T 148, T 265, T 267, AND T 283Precision Statements for AASHTO Standard Methods of Test T 148, T 265, T 267, AND T 283
February 8, 2011
TRB’s National Cooperative Highway Research Program (NCHRP) Research Results Digest 351: Precision Statements for AASHTO Standard Methods of Test T 148, T 265, T 267, AND T 283 summarizes the findings of four interlaboratory studies conducted in 2009 and 2010 to develop precision statements for the AASHTO standard methods of measuring length of drilled concrete cores, laboratory determination o...


More.....
Transportation Research Board. 500 Fifth St. NW, Washington, D.C. 20001
Copyright © 2012. National Academy of Sciences. All Rights Reserved.