Transportation Research Institute, Technion - Israel Institute of Technology, Haifa, Israel.
Technion Statistical Laboratory, Technion - Israel Institute of Technology, Haifa, Israel.
Accid Anal Prev. 2019 Jan;122:108-118. doi: 10.1016/j.aap.2018.10.003. Epub 2018 Oct 16.
Constructing proper shoulders may improve road safety on two-lane roads. Previous research reported crash reductions following shoulder widening. This study aimed to examine the relationship between shoulder characteristics and crash occurrences on two-lane rural roads in Israel. The study database combined information on crash numbers, traffic volumes and road infrastructure characteristics of 3594 road sections. To examine a relationship between shoulder characteristics and crashes, given other road characteristics, two types of statistical models were developed: case-control and negative-binomial regression models, for several crash types. We found that the impacts of shoulder width and other road characteristics on crashes were generally consistent across various models and crash types, where a non-monotonous link between the shoulder width and crashes was typically observed. For various crash types, the models showed an increase in crash risk with an initial extension of the total shoulder, up to 2.2 m, and a consequent decrease in crashes with a further shoulder widening, over 2.2 m, by 2-6% and 1-4%, respectively, for each 0.1 m of shoulder extension. An increase in the width of unpaved shoulders, over 0.9 m, was associated with increased crash risk, in injury and total crashes, by 5% for each 0.1 m of shoulder extension. Lowest crash risks were found for total shoulder widths of about 3 m or more, but also for narrow total shoulders, below 1 m. Conversely, medium total shoulders, of 1.8-2.4 m in width, and unpaved shoulders of over 1 m, were associated with an increase in crash risk and, hence, are not recommended for use. The tools developed in the study may assist in decision-making during the design stages of a new road or upgrading existing road sections, on two-lane local roads.
合理设置路肩可能会提高双车道道路的行车安全性。已有研究表明，拓宽路肩可以降低事故发生率。本研究旨在探讨以色列双车道农村道路路肩特征与事故发生之间的关系。该研究数据库结合了 3594 个路段的事故数量、交通量和道路基础设施特征信息。为了检验路肩特征与事故之间的关系，考虑到其他道路特征，我们开发了两种类型的统计模型：病例对照和负二项回归模型，用于几种事故类型。我们发现，路肩宽度和其他道路特征对事故的影响在各种模型和事故类型中基本一致，通常观察到路肩宽度与事故之间存在非单调关系。对于各种事故类型，模型显示，随着总路肩的初始扩展（2.2 米以内），事故风险增加，而随着路肩进一步拓宽（2.2 米以上），事故风险相应降低，分别增加了 2-6%和 1-4%，每个 0.1 米的路肩延伸。未铺砌路肩的宽度增加（0.9 米以上）与受伤和总事故的事故风险增加有关，每个 0.1 米的路肩延伸增加 5%。总路肩宽度约为 3 米或更大，以及总路肩宽度较窄（1 米以下）时，事故风险最低。相反，总路肩宽度为 1.8-2.4 米，未铺砌路肩宽度超过 1 米，则与事故风险增加有关，因此不建议使用。本研究开发的工具可在新道路设计或现有道路路段升级阶段，为双车道地方道路的决策提供参考。
