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Development of the AASHTO Highway Safety Manual began from a TRB conference session and a workshop, both held in 1999, that identified the need for a traffic safety document analogous to the role of the Highway Capacity Manual for traffic operations. NCHRP Research Report 1140: Quantitative Safety Analyses for Highway Applications, from TRB’s National Cooperative Highway Research Program, describes […]
Bridge and tunnel strikes inflict serious damage to vehicles, highway bridges, and tunnels; cause injuries and fatalities; and impose detours and costly delays on highway users. Attempts by state departments of transportation (DOTs) and other bridge and tunnel owners to prevent bridge and tunnel strikes include signing, lighting, height detection systems, and actuated warning devices. […]
Transportation is fundamental to the vibrancy of the Nation and facilitates economic prosperity and quality of life. It enables people to engage in productive pursuits and experience the social interactions that take full advantage of geographic specialization and diffusion. An efficient and resilient transportation system and its seamless operation underpin the overall efficiency and resilience […]
Most partially automated systems have safeguards to counteract driver disengagement, but little is known about how they affect driver behavior over time. This naturalistic observation study investigated how the behavior of 14 drivers who had no previous partial automation experience evolved over a month of exposure to the Tesla Autopilot system in a model year […]
This report identifies common issues that result in change orders and cause project delays and overruns, organized into three main categories relating to the quality of technical project development work, influences of organizational culture, and uncertainty introduced by financial forces. It also describes best practices to minimize and mitigate change orders and highlights noteworthy project […]
In 2021, Congress passed the Infrastructure Investment and Jobs Act, also known as the Bipartisan Infrastructure Law (BIL), which reauthorized surface transportation programs. This legislation allocated approximately $350 billion over a 5-year period to Federal highway programs with a focus on repairing roadways and bridges, with the opportunity to create jobs, boost the economy, and […]
Many of the bridges that Americans drive over each day need repairs. To help repair and replace these bridges, the Infrastructure Investment and Jobs Act established a new grant program—the Bridge Investment Program. The act provided $12.5 billion over 5 years for the program. The act also includes a provision for GAO to review DOT’s […]
The Alabama Crash Facts Book (CFB) is an annual publication produced in part by CAPS that provides a wide breadth of traffic safety statistics for a variety of constituencies. While most of the users of the CFB are traffic safety personnel, this publication is also intended to serve as a public information conduit. Read the […]
This research report has valuable insights for city planners, legislators, public health organizations, bike advocacy groups, insurance companies, and researchers. It examines the effects of Stop-as-Yield laws on bicyclist safety and behavior, showing associations with reduced crash rates at specific intersections. These findings can inform policy development, infrastructure planning, public health initiatives, and further academic […]
The Drivers’ Education Demo to Reduce Pedestrian and Bicyclist Fatalities effort was designed to examine the current state of driver education and training and the post-licensing improvement courses available in the United States with respect to the level of emphasis on pedestrians, bicyclists, and other micro-mobility road users and the specific topics (e.g., maneuvers, contextual […]