Comprehensive investigation of crashes associated with citywide speed limit reduction in Seattle, Washington

IF 2.4 Q3 TRANSPORTATION
Jin Wang
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Abstract

Road traffic crashes are a leading cause of fatalities and injuries worldwide, prompting authorities to implement various strategies to enhance road safety. One common approach involves lowering speed limits in an effort to mitigate the severity of crashes and improve overall traffic safety. Seattle, Washington has been lowering its citywide default speed limits on municipal roads since 2016, among several cities in the US. This research paper presents a comprehensive investigation of the impact of these speed limit reductions on various safety indicators, such as the crash frequency, crash severity, crash characteristics, crash type, crash location, contributing factors, and overall traffic safety performance. The study employs a comprehensive dataset encompassing several years before and after the implementation of lower speed limits. Data analyses indicate varying changes in crash severity distribution between before and after periods in Seattle. Fatal and incapacitating crashes in Seattle decreased by 19% after the initial speed limit lowering in 2016 and further decreased by 3% after the second speed limit lowering in 2018. Pedestrian-involved crashes experienced a 26% significant decrease while speeding-related had a 16% decrease after the city implemented lowering speed limits. There was also a statistically significant 4% decrease in property damage only collisions and a 7% decrease in parked car crashes. Distracted driving / inattention-related crashes also decreased by 4%. The Mid-Block (but intersection related) crashes saw a significant decrease by 6%, and Driveway Junction related crashes decreased by 1%. The findings provide insights into the effectiveness of speed limit reductions in enhancing road safety in urban environments. The findings contribute to the existing body of knowledge on speed management strategies and their impact on traffic safety. The outcomes of this study can inform transportation policymakers and practitioners in Seattle and other urban areas as they make informed decisions regarding speed limit regulations and road safety measures.

对华盛顿州西雅图市全市范围内降低车速限制引发的交通事故进行全面调查
道路交通事故是世界范围内造成人员伤亡的主要原因,促使有关部门实施各种战略来加强道路安全。其中一种常见的方法是降低车速限制,以减轻交通事故的严重程度,提高整体交通安全。在美国多个城市中,华盛顿州西雅图市自 2016 年起开始降低全市市政道路的默认速度限制。本研究论文全面调查了降低速度限制对各种安全指标的影响,如碰撞频率、碰撞严重程度、碰撞特征、碰撞类型、碰撞地点、诱因以及整体交通安全性能。该研究采用了一个全面的数据集,涵盖了降低车速限制实施前后的几年时间。数据分析显示,西雅图在实施限速前后的车祸严重程度分布发生了不同的变化。2016 年首次降低车速限制后,西雅图的致命和致残碰撞事故减少了 19%,2018 年第二次降低车速限制后进一步减少了 3%。在该市实施降低车速限制后,与行人有关的碰撞事故大幅减少了 26%,而与超速有关的碰撞事故则减少了 16%。此外,仅造成财产损失的碰撞事故在统计上也大幅减少了 4%,而停放车辆碰撞事故则减少了 7%。与分心驾驶/注意力不集中有关的碰撞事故也减少了 4%。中间街区(但与交叉路口有关)的碰撞事故大幅减少了 6%,与车道交界处有关的碰撞事故减少了 1%。研究结果为降低车速限制在加强城市环境道路安全方面的有效性提供了启示。研究结果为现有的车速管理策略及其对交通安全影响的知识体系做出了贡献。这项研究的结果可以为西雅图和其他城市地区的交通决策者和从业人员提供信息,帮助他们就限速法规和道路安全措施做出明智的决策。
本文章由计算机程序翻译,如有差异,请以英文原文为准。
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来源期刊
CiteScore
5.00
自引率
12.00%
发文量
222
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