Abstract

Despite numerous past studies conducted on traffic barriers, research is still needed to analyze the performance of traffic barriers on superelevated horizontal curves. Based on the literature of traffic barrier studies, the effect of geometric features of traffic barriers (such as height and post-spacing) on crashes involving horizontal curves has not been investigated considering actual crash data analysis. This paper seeks to study the effect of various variables affecting the severity of traffic barrier crashes on horizontal curves. Geometric features of 95 miles of traffic barriers were collected, conducting a field inventory on all interstate roads in Wyoming. All the traffic barriers collected were located on horizontal curves with at least one historical crash report between 2008 and 2017. Random-parameters ordered logit was used to develop two models to investigate the factors impacting the severity of horizontal curve crashes involving side and median traffic barriers, respectively, on interstate roads. Based on the results, median box beam barriers with a post-spacing of 6.1 ft resulted in lower injury severity. Median W-beam barriers with a height taller than 31 inches were involved with a higher probability of severe collisions. Side box beam barriers located on the front side-slope were also more likely to increase the severity of crashes.

摘要

尽管过去对交通障碍进行了许多研究，但仍需要研究来分析交通障碍在超高水平曲线上的性能。根据交通障碍研究的文献，考虑到实际碰撞数据分析，尚未研究交通障碍的几何特征（例如高度和后间距）对涉及水平曲线的碰撞的影响。本文旨在研究影响交通护栏碰撞严重程度的各种变量对水平曲线的影响。收集了 95 英里交通障碍的几何特征，对怀俄明州的所有州际公路进行了实地清查。收集到的所有交通障碍都位于水平曲线上，至少有一份 2008 年至 2017 年间的历史事故报告。随机参数有序 logit 用于开发两个模型，以研究影响州际公路上分别涉及侧面和中间交通障碍的水平曲线碰撞严重程度的因素。根据结果​​，后间距为 6.1 的中间箱形梁屏障 英尺导致较低的伤害严重程度。高度高于 31 英寸的中间 W 型梁障碍物发生严重碰撞的可能性更高。位于前边坡的侧箱梁护栏也更有可能增加碰撞的严重程度。