Examining the effect of speed, roadside features, and roadway geometry on crash experience along a rural corridor

作     者：Donald C. Watson Jr. Ahmed Al-Kaisy Nathan D. Anderson 

作者机构：289 North Lake Lulu Drive Winter Haven FL 33880 USA Western Transportation Institute Montana State University 213Cobleigh Hall Bozeman MT 59717 USA 

出 版 物：《Journal of Modern Transportation》 (现代交通学报（英文版）)

年 卷 期：2014年第22卷第2期

页      面：84-95页

学科分类：03[法学] 1201[管理学-管理科学与工程(可授管理学、工学学位)] 0808[工学-电气工程] 0809[工学-电子科学与技术（可授工学、理学学位）] 08[工学] 0838[工学-公安技术] 0802[工学-机械工程] 0814[工学-土木工程] 0812[工学-计算机科学与技术（可授工学、理学学位）] 0823[工学-交通运输工程] 0801[工学-力学（可授工学、理学学位）] 0306[法学-公安学] 

基　　金：the financial support to this research by the National Science Foundation (NSF) through the Western Transportation Institute (WTI) of Montana State University 

主　　题：Crashes Rural Analysis Alignment Speed Roadside 

摘      要：This paper presents a current investigation into crash experience along a 15.7-mile rural corridor in southwest Montana with the aim of better understanding crash causal factors along the corridor. The study utilized ten years of crash data, geometric data, and observed freeflow speed data along the corridor. A systematic approach was used where every tenth of a mile was described in term of the crash experience, speed, alignment, and roadside features. Using bivariate and multivariate statistical anal-yses, the study investigated the crash experience along the corridor as well as some of the underlying relationships which could explain some of the crash causal factors. Results show a strong association between crash rates and horizontal curvatures even for flat curves that can be negotiated at speeds above the posted speed limit, per the highway design equations. Higher crash rates were also found to be associated with the difference between the observed free-flow speeds and the speed dictated by the curve radius or sight distance as per the design equations. Further, results strongly support the safety benefits of guardrails as evidenced by the lower crash rates and severities. The presence of fixed objects and the steepness of side slopes were also found to have an effect on crash rates and severities.