Abstract

Road safety is a major public health concern in our society. Effective road design and accurate safety analyses must be a component of programs focused on reducing and eliminating roadway injuries and deaths. Various methodologies exist to determine the expected number of crashes on rural two-lane rural roads. This research compares different procedures which allow for the estimation of the number of crashes on homogeneous road segments. In this effort, a total of 27 two-lane rural road sections located in North Carolina were considered, resulting in 59 homogeneous road segments composed of 350 horizontal curves and 375 tangents along 150 km of road. Four methods were applied to the selected roadways: the Highway Safety Manual predictive method, two jurisdiction-specific Safety Performance Functions (SPFs), and a SPF which includes a consistency parameter.

This research found that the use of SPFs which incorporate a consistency parameter allows highway engineers to consider human factor impacts on road safety assessment. The use of a consistency parameter can also simplify the crash estimation process. Analysis methods which only included local geometric variables provided unreliable results due to the calibration of only the specific road elements instead of their relationship with other road elements along homogeneous road segments.

摘要

道路安全是我们社会的主要公共卫生问题。有效的道路设计和准确的安全分析必须成为旨在减少和消除道路伤害和死亡的计划的组成部分。存在多种方法来确定乡村双车道乡村道路上的预期碰撞次数。这项研究比较了不同的程序，这些程序允许估计同质路段上的碰撞次数。在这项工作中，总共考虑了位于北卡罗来纳州的 27 个双车道农村路段，产生了 59 个均质路段，由 350 条水平曲线和 375 条切线组成，沿 150 公里的道路。四种方法应用于选定的道路：公路安全手册预测方法，两个特定于司法管辖区的安全性能函数 (SPF)，

这项研究发现，使用包含一致性参数的 SPF 允许高速公路工程师考虑人为因素对道路安全评估的影响。一致性参数的使用还可以简化碰撞估计过程。由于仅校准特定道路元素而不是它们与沿同类路段的其他道路元素的关系，因此仅包括局部几何变量的分析方法提供的结果不可靠。