As freight transportation volumes have grown rapidly—further spurred by pandemic-driven e-commerce growth—state departments of transportation (DOTs) have become increasingly reliant on probe data to monitor freight infrastructure performance, manage demand, and understand freight infrastructure needs. NCHRP Synthesis 611: Use of Probe Data for Freight Planning and Operations , from TRB's National ...

Most state departments of transportation (DOTs) use social media to broadcast information and monitor emergencies, but few rely heavily on social media data. The most common barriers to using social media for emergencies are personnel availability and training, privacy issues, and data reliability. NCHRP Synthesis 610: Leveraging Social Media Data for Emergency Preparedness and Response , from TRB...

State departments of transportation (DOTs) are facing the challenge of maintaining and preserving local environmental systems while meeting transportation needs. Stormwater best management practices (BMPs) can help mitigate ecological impacts, and unmanned aerial systems (UAS) can be used to track, monitor, and document BMPs throughout their life cycle. NCHRP Synthesis 609: Use of Unmanned Aerial ...

In comparable private sectors, incentive and disincentive programs have effectively promoted safe behaviors by employees. However, state departments of transportation (DOTs) have unique limitations and restrictions on their ability to financially incentivize safe actions by highway construction and maintenance crews or, in some cases, implement corrective actions to disincentivize unsafe actions. ...

Road tunnels employ a multitude of functional systems that include a variety of equipment: lighting, ventilation, power supply, fire protection systems such as fixed fire-fighting systems, fire detection systems, communications systems and operational devices, supervisory control and data acquisition, closed circuit television, variable message signs, and radio. Maintenance of these systems is cri...

Most state departments of transportation (DOTs) are aware of the importance of integrating freight and active transportation, but there is a lack of coordination and standardized protocols for doing so. NCHRP Synthesis 606: Integrating Freight and Active Transportation into Policies, Programs, Plans, and Project Development , from TRB's National Cooperative Highway Research Program, documents stat...

State departments of transportation (DOTs) are working to deploy electric vehicle (EV) charging infrastructure, but face challenges and need AASHTO-type guidelines to help with deployment. NCHRP Synthesis 605: Electric Vehicle Charging: Strategies and Programs , from TRB's National Cooperative Highway Research Program, documents current strategies and practices in use by state DOTs to facilitate a...

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...

There are a variety of ways to achieve tolerances in steel bridge fabrication and erection. One common method is to use shop assembly, which is the process of assembling steel members in the shop before they are erected on site. Another method is to use oversize holes, which are holes that are slightly larger than the required size. NCHRP Synthesis 603: Practices for Steel Bridge Fabrication and E...

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...