Characteristics of and Potential Treatments for Crashes on Low-Volume, Rural Two-Lane Highways in Texas.

摘要

Low-volume, rural two-lane highways carry less than 8 percent of the total vehicle miles on state-maintained (or on-system) highways and have approximately 11 percent of the total on-system vehicle crashes. These roadways also have relatively more severe injuries when vehicle crashes do occur. For example in 1999, about 26 percent of the Texas on-system crashes were KAB crashes (i.e., fatal, incapacitating injury or non-incapacitating injury crashes), while over 40 percent of the crashes on low-volume on-system roads in 1999 were KAB crashes. In general, crashes on low-volume, rural two-lane highways occur between intersections by a single vehicle running off the road. Crashes on curves and in dark, non-lighted conditions are more common on low-volume, rural two-lane highways than on urban roads. The study in crash characteristics also demonstrated that more KAB crashes occurred in eastern counties than western counties in Texas. A sample of counties was selected to investigate which regional characteristics are associated with high and low crash rates. In general, sites in the eastern counties had less driver-friendly characteristics-more horizontal and vertical curves, narrower lanes and/or shoulders, less forgiving roadside development, higher access density, and higher roadside development scores.