Multiple Geometric Factors Contributing to Mountainous Freeway Crashes: A Case Study of Changjin Freeway in Jiangxi, China

摘要

Many previous researches have analyzed the causes of freeway accidents, especially for those in the mountainous areas, but few of them have put deep insight into the geometric factors. Using 1,023 crash records during the period of 2006-2012 from Changjin Freeway in Jiangxi, China, this research evaluated the relation between contributory geometric factors and crash rate. Geometric factors were classified into three categories: vertical alignment, horizontal alignment, and cross section. Then detailed effects of geometric variables are separately discussed and quantified through the relation with crash rate (CR). It was found that the CR value is greater at minor radius and long-down grade sections. Additionally, segments of angle of deflection varying over 17-25° and wider cross sections are much safer, compared with other locations.