Dynamic curbside management has been the purview of cities, with much of the relevant research and guidance directed toward local transportation agencies. However, state departments of transportation, metropolitan planning organizations, and other regional agencies can be important partners for these local entities because, in many cases, roadways and other curb zone elements are part of the regional or state network. The TRB National Cooperative Highway Research Program's NCHRP Web-Only Document 340: Dy...

Although only 19% of the population live in rural areas, more than 70% of the U.S.’s four million miles of roadways are in rural areas. The rural transportation system also includes numerous airports; railways; inland and coastal waterways; rural and intercity buses; and bicycle, pedestrian, and multi-use paths and trails. In addition, approximately 47% of the nation’s motor vehicle fatalities occur in rural areas. The TRB National Cooperative Highway Research Program's  NCHRP Research Report 988: R...

The passage of Dodd-Frank and the COVID-19 pandemic are among the factors that have made the environment for tax-exempt debt issuers increasingly challenging and complex. The TRB National Cooperative Highway Research Program's NCHRP Research Report 990: Guidebook for Effective Policies and Practices for Managing Surface Transportation Debt is designed to help surface transportation agencies improve the development and execution of debt management policies, procedures, and practices. Supplemental to the r...

Subsurface drainage is known to pavement professionals to be an important factor affecting pavement performance and preservation of public investment, and numerous studies have emphasized its importance. The TRB National Cooperative Highway Research Program's NCHRP Synthesis 579: Subsurface Drainage Practices in Pavement Design, Construction, and Maintenance documents the current state of practice by departments of transportation (DOTs) for subsurface drainage, which is not always considered as a critica...

Since 1984, AASHTO’s “Green Book” and other roadway design criteria have been primarily based on a functional classification system of a hierarchical network composed of arterials, collector, and local roads. However, this hierarchical functional classification system is in lack of flexibility in design, especially for a modern multimodal roadway system. The TRB National Cooperative Highway Research Program's NCHRP Web-Only Document 320: Aligning Geometric Design with Roadway Context drafts the Faci...

Excessive contract time is costly because it extends a construction crew’s exposure to traffic, prolongs the inconvenience to the public, and subjects motorists to less than desirable safety conditions for longer periods. The TRB National Cooperative Highway Research Program's NCHRP Web-Only Document 298: Developing a Systematic Approach for Determining Construction Contract Timeseeks to provide a systematic approach for determining construction contract time for a wide spectrum of highway projects. The ...

Cracking is a primary distress mode of asphalt pavements that creates the need for their rehabilitation. All types of asphalt pavement cracking—thermal, reflection, fatigue, and topdown— are affected by numerous factors and their interactions. The TRB National Cooperative Highway Research Program's NCHRP Research Report 987: Ruggedness of Laboratory Tests for Asphalt Mixture Cracking Resistance presents the results of ruggedness testing of eight laboratory tests for the cracking resistance of asphalt mix...

Many technical and institutional issues related to estimating and reducing greenhouse gas emissions (GHGs) lie across a wide spectrum of the activities undertaken by state departments of transportation (DOTs). The TRB National Cooperative Highway Research Program's NCHRP Web-Only Document 308: Methods for State DOTs to Reduce Greenhouse Gas Emissions from the Transportation Sector documents the research effort for an NCHRP project that focused on developing a guide for state DOTs on reducing GHG emission...

Motor vehicle crashes cost society more than $230 billion annually. On an average day, 117 fatal crashes occur on U.S. roadways, and 30 percent of these fatalities are people under the age of 25. In total, this amounts to a societal loss of $630 million per day. The TRB National Cooperative Highway Research Program's NCHRP Web-Only Document 319: Roadside Safety Analysis Program (RSAP) Update details a safety-analysis program for run-off-road (ROR) traffic crashes, which account for almost one-third of th...

The Highway Safety Manual (HSM) provides a predictive method for two- and four-lane urban and suburban arterial facilities with both undivided and divided cross-sections. The manual does not cover arterials with six or more lanes or one-way streets. The TRB National Cooperative Highway Research Program's NCHRP Web-Only Document 318: Safety Prediction Models for Six-Lane and One-Way Urban and Suburban Arterials documents a safety prediction method for six-or-more-lane and one-way urban and suburban arteri...