翟伟 邬岚 杨晟

摘 要：为研究基于中央左转车道缩减设计中交叉口的安全性，分析车道缩减后交叉口冲突特性，并建立冲突评价模型，基于车道缩减前后的仿真，通过冲突评价模型（Surrogate Safety Assessment Model，SSAM）分析冲突指标，研究车道缩减前后冲突时间、相遇时间、初始减速度、最大速度和相对速度的变化情况。研究结果表明：对于无信号控制交叉口，车道缩减前后冲突点数目变化不大，冲突点的位置有改变，车辆运行影响不明显;对于信号控制交叉口，冲突点数目大幅下降，同时车辆运行的最大速度提高了44.8%，相对速度提高了64.6%。在信号控制的交叉口采用窄马路理念的车道缩减设计，可以有效提高信号交叉口的运行效率，保证车辆通过信号交叉口的安全性。

关键词：交通工程;车道缩减;交通仿真模拟;冲突评价模型;冲突评价指标;安全性

中图分类号：U491.3     文献标识码：A   文章编号：1006-8023（2021）03-0103-08

Abstract：In order to study the safety of the intersection after lane reduction based on the twowayleftturn lane， the conflict characteristics of the intersection after lane reduction were analyzed and the conflict evaluation model was established. Based on the simulation before and after lane reduction， the conflict indicators were analyzed by the conflict evaluation model （Surrogate Safety Assessment Model， SSAM）. Meanwhile the changes in conflict time， encounter time， initial deceleration， maximum speed and relative speed before and after lane reduction were studied. The research results showed that the number of conflict points at unsignalized intersections did not change much， only the location of the conflict points was changed， and the impact to the vehicle operation was not obvious. For the signalized intersection， the number of conflict points was decline significantly. Further more， the maximum speed of the vehicle operation increased by 44.8%， and the relative speed increased by 64.6%. The above results showed that the use of lane reduction design based on narrow road concept at signalized intersections can effectively improve the operating efficiency of signalized intersections and ensure the safety of vehicles passing through the intersections.

Keywords：Traffic engineering; lane reduction; traffic simulation; Surrogate Safety Assessment Model; conflict evaluation index; safety

0 引言

車道缩减是一种在道路红线变窄、道路施工或发生重大交通事故的情况下，通过减少车道数，依旧能够保持车辆正常行驶的道路横断面改造方案。该方案主要围绕“完善道路功能、改善秩序、增加人本活动空间、提升品质”等设计目标展开，通过增设中央左转车道，实现道路缩减，合理设置自行车道及人行道、用绿化带隔离不同类型的车道，以此来完善道路功能，建设一个安全、运转良好、有生活品质的道路环境[1-4]。

国外对于车道缩减的研究大多集中在车道组织方案的经济效益和安全……