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This report documents the results and conclusions of an initial experiment that examined human factors issues in the use of adaptive cruise control (ACC) and a hypothetical cooperative ACC (CACC), which is an ACC system enhanced with vehicle-to-vehicle (V2V) communications to share information on speed, brake position, and distance between vehicles.
Caitlin Hughes, director of the Federal Highway Administration’s office of freight management and logistics, noted in a presentation at the American Association of State Highway and Transportation Officials 2018 Joint Policy Committee meeting in Spokane, Washington on July 18 that a nationwide truck parking survey now expected to start this August is going to be […]
The overall objectives of this research were to identify and explore alternative safety data sources and analysis perspectives, and demonstrate the potential utility of these alternative approaches in increasing understanding of precipitating events and predisposing factors for crashes occurring on horizontal curves and at unsignalized intersections along rural two-lane roads. The project team executed the […]
The U.S. Department of Transportation’s Federal Highway Administration (FHWA) today launched a series of meetings with key stakeholders to discuss the ramifications of automated vehicles on U.S. roads. The “national dialogue” meetings are being held across the country to engage a diverse group of stakeholders from industry and the public sector to understand the key […]
U.S. DOT Federal Highway Administration: Traffic Volume Trends is a monthly report based on hourly traffic count data reported by the States. These data are collected at approximately 4,000 continuous traffic counting locations nationwide and are used to estimate the percent change in traffic for the current month compared with the same month in the […]
The modern highway system has experienced considerable changes since the interstate system and other limited access highways were first designed and constructed in the mid-1900s. Population movement outside of cities and the increased movement of passenger and freight traffic have led to increased congestion and necessitated new approaches for maintaining mobility. Mobility and capacity enhancements, […]
FHWA-HRT-17-066 The Federal Highway Administration established the Development of Crash Modification Factors (DCMF) program in 2012 to address highway safety research needs for evaluating new and innovative safety strategies (improvements) by developing reliable quantitative estimates of their effectiveness in reducing crashes. The ultimate goal of the DCMF program is to save lives by identifying new […]
There are many problems that can occur at an unsignalized intersection. Problems could be specific to an individual intersection, occur along a section of road with successive unsignalized intersections, or be a systemic problem throughout a jurisdiction. The following represent common problems experienced at unsignalized intersections that are addressed in the Unsignalized Intersection Improvement Guide […]
AASHTO: Motor vehicle travel on all U.S. highways and streets increased 1.2 percent in October from a year earlier – adding 3.3 billion more vehicle miles – and continued a string of record-high volume levels. The Federal Highway Administration in its latest monthly “Traffic Volume Trends” report said motorists racked up an estimated 275 billion […]
Office of Highway Policy Information: Traffic Volume Trends is a monthly report based on hourly traffic count data reported by the States. These data are collected at approximately 4,000 continuous traffic counting locations nationwide and are used to estimate the percent change in traffic for the current month compared with the same month in the […]