Many bridges are built without accommodations for active transportation users and only serve motorized traffic. The pedestrians and bicyclists who rely on these bridges are exposed to safety-related concerns and their access to equal employment opportunities and essential services may be hindered. The TRB National Cooperative Highway Research Program's NCHRP Synthesis 604: Practices for Adding Bic...

The increased frequency of extreme rainfall events, inland and coastal flooding, and other water-related stressors poses challenges to roadway infrastructure. The TRB National Cooperative Highway Research Program's NCHRP Synthesis 602: Resilient Design with Distributed Rainfall-Runoff Modeling documents the practices of state departments of transportation on the use of DRRMs and identifies state D...

More than 15 years have passed since the U.S. transportation industry started its transition from allowable stress design (ASD) to load and resistance factor design (LRFD). For geotechnical design, the AASHTO LRFD Bridge Design Specifications includes provisions that allow state departments of transportation (DOTs) to develop their own design methods and resistance factors. The TRB National Cooper...

As-builts, inclusive of utility as-builts—which are the recorded representation of the built or maintained infrastructure and show the actual location, dimensions, geometry, and other attributes of the work as completed—can provide a baseline for new design projects by providing information on current transportation infrastructure and other facilities such as underground and overhead utilities. Th...

Bioretention stormwater control measure (BSCM) runoff treatment provides several benefits over other stormwater control measures (SCMs) and is increasingly used by state departments of transportation (DOTs) to help manage stormwater to meet stormwater permit requirements. The TRB National Cooperative Highway Research Program's NCHRP Synthesis 599: Practices for Bioretention Stormwater Control Meas...

Curing is a major contributor to the short- and long-term performance of concrete pavements. Effective curing controls moisture loss and maintains adequate temperature of concrete pavements to allow for the continuation of cement hydration and formation of hydrated gel necessary to develop desired strength and durability. The TRB National Cooperative Highway Research Program's NCHRP Synthesis 598:...

Micromobility vehicles and shared micromobility technologies are deploying rapidly in many cities across the United States and internationally. Lacking a standard definition, micromobility can include any small, personal transportation technology that travels slower than 20 to 30 miles per hour, may be motorized, and is frequently operated on pedestrian- or bicycle-oriented infrastructure (often, ...

There are few inventories of state investments in active transportation, at least partially because there is no federally mandated requirement to report on these investments. They are often accomplished as part of larger infrastructure projects, in order to realize the efficiencies inherent in making changes across modes on a network at the same time. The TRB National Cooperative Highway Research ...

Incompatibility between aggregate type and asphalt binder, presence of standing water or water under pressure in the pavement layers, and improper construction practices are some of the many factors that influence moisture susceptibility of flexible pavements. The TRB National Cooperative Highway Research Program's NCHRP Synthesis 595: Practices for Assessing and Mitigating the Moisture Susceptibi...

Technology solutions are in no short supply for state departments of transportation across the United States. With advancements in geospatial accuracy, cost reduction for technology components, and a need for effective staff utilization, a wealth of products and systems are becoming attractive options in the delivery of highway projects. The TRB National Cooperative Highway Research Program's NCHR...

State departments of transportation (DOTs) have been investing in 3D modeling and sharing 3D digital models with contractors. Some DOTs have piloted the use of 3D digital models as contract documents, others continue to provide contractors with 3D digital models for information purposes, and some have not begun using 3D digital models in construction. The TRB National Cooperative Highway Research ...

The Highway Safety Improvement Program (HSIP) is a core federal-aid highway program with the purpose of achieving significant reductions in fatalities and serious injuries on all public roads. Although there are federal requirements that guide state HSIP efforts, there are several variations in how state departments of transportation (DOTs) identify, prioritize, and evaluate HSIP projects. The TRB...

Safety and health programs are vital to the success of state departments of transportation (DOTs). While the safety of all DOT employees is paramount, maintenance and other field workers are exposed to unique hazards that demand a higher level of management than traditional office-based positions. The TRB National Cooperative Highway Research Program's NCHRP Synthesis 591: Use of Safety Management...

For years, state departments of transportation (DOTs) were solely responsible for quality control (QC) and performed testing and inspection to verify construction quality. However, since the 1970s, many state DOTs have transferred the responsibility for QC processes of their highway-construction projects to contractors. The TRB National Cooperative Highway Research Program's NCHRP Synthesis 590: A...

Automated collection of pavement data allows agencies to collect data on pavement health, including cracking, rutting, faulting, and roughness, at highway speeds. This provides important information for better pavement decision-making. The TRB National Cooperative Highway Research Program's NCHRP Synthesis 589: Automated Data Collection and Quality Management for Pavement Condition Reporting docum...

While there are no national standards for rock slope design and rockfall management, many state departments of transportation (DOTs) have developed their own design goals and objectives. The TRB National Cooperative Highway Research Program's NCHRP Synthesis 588: Design Practices for Rock Slopes and Rockfall Management documents DOT practices for the design of rock slopes and rockfall mitigation s...

To make work zones safer, state departments of transportation (DOTs) use smart technologies with specialized components, such as sensors, communications, software, and electronic equipment, to manage traffic and operations and disseminate traveler information. The TRB National Cooperative Highway Research Program's NCHRP Synthesis 587: Use of Smart Work Zone Technologies for Improving Work Zone Sa...

Although the use of recycled asphalt materials (RAM) in new asphalt mixtures can reduce the amount of virgin and nonrenewable materials required and increase the rutting resistance of pavements, it may also compromise cracking resistance. To mitigate this issue, asphalt mixtures containing RAM may require the use of a softer binder or recycling agent (RA). The TRB National Cooperative Highway Rese...

Initial efforts to define and collect bridge element data in the United States started in the late 1990s with the development and implementation of bridge management systems (BMSs). Over the years, the bridge management community provided feedback and made suggestions to improve the bridge element inspection methodology. The TRB National Cooperative Highway Research Program's NCHRP Synthesis 585: ...

Visualizations are tools for analyzing, reporting, and communicating the complexities of a transportation system and for synthesizing these intricacies into presentations that can be easily understood. The TRB National Cooperative Highway Research Program's NCHRP Synthesis 584: Visualization of Highway Performance Measures documents current practices and methods used by state departments of transp...