Travel Behavior

Fatal or injury collisions in California must be reported to the California Highway Patrol (CHP) for inclusion in the Statewide Integrated Traffic Records System (SWITRS). After records have been entered into SWITRS they are made publicly available and are accessible through the CHP’s report and data retrieval site called I-SWITRS. However, records accessed in SWITRS are considered provisional and can be updated several years after initial entry. This includes the injury severity level of collisions. If the collision data was accessed prior to an injury severity update, the agency...

Traffic safety researchers have long argued that driver behavior outweighs physical elements (such as road design) as a causal factor in motor vehicle collisions. A fundamental causal component of pedestrian-vehicle collisions is also behavior—that of the driver and that of the pedestrian. One determinant of this behavior may be whether the driver, the pedestrian, or both understand the motor vehicle code, which demarcates right-of-way in pedestrian-vehicle interactions. That is, inappropriate or unlawful behavior may occur because the law is not understood or is misunderstood. Previous...

Being a public resource, the roadway space was distributed between different road users based on the Passenger-Car-Unit (PCU) concept. However, this concept tends to under estimate the capacity of public transportation and non-motorized travel. To improve the traditional car-oriented design to become more human-oriented, this study proposed a Passing-passenger-unit (PPU) and the method to observe the PPU in roadway level and area level. The PPU data were collected for urban arterials and residential areas in China to test the method and to compare the right-of-way distribution at different...

This project examined the safety and demand issues for pedestrians and bicyclists at multi-lane roundabouts through a literature review, case studies, in-field counts and surveys, focus groups, and video analysis. This document presents research findings, synthesizes current information on best practices, and makes recommendations to assist local agencies planning and designing safer multi-lane roundabouts. These findings should help local agencies and Caltrans create roundabouts that better and more safely address the needs of bicyclists and pedestrians. The current literature is referred...