基于碰撞时间的大流量隧道口追尾隐患概率模型构建

A rear-end collision probability model at heavy-traffic tunnel entrance based on time-to-collision

城市隧道交通拥堵问题日益严重,追尾事故常发,在高峰时段尤为突出.为提高隧道口通行能力、减少因事故产生的拥堵,基于上海长江隧道入口的视频采集的交通流数据,对隧道口各车道的车流特征进行了统计分析,并对实际观测的碰撞时间进行了分布拟合,结合安全碰撞时间标准构建了追尾隐患概率模型,为降低大流量隧道口追尾事故隐患提供参考.研究结果表明:流量较大时,隧道口行驶车速及跟驰车辆的速度差与追尾隐患概率显著正相关;此时不宜采用固定限速值对隧道口进行管理,建议在隧道口前设置小型车专用道或者在大流量时段对大型车(如货车)实施限行.本模型可以有效评价隧道口追尾事故隐患,为改善措施提供理论基础,保障隧道的安全运营.

Urban tunnels have been greatly affected by the increasing traffic congestion,which leads to frequent rear-end collisions,especially during the peak periods.In order to improve the traffic capacity of tunnels and ease the congestions caused by rear-end collisions,the traffic flow data are collected through the video recording of the entrance of the Shanghai Yangtze River Tunnel,where the traffic flow characteristics of each lane are statistically analyzed.Then the observed time-to-collision distribution is fitted.The time-to-collision safety criterion is used to construct a probability model of rear-end collisions,so as to provide a reference for reducing the risk of rear-end collision at tunnel portal with heavy traffic.The results indicate that the driving speed and the speed differences of the following vehicles have a strong positive correlation with the probability of rear-end collisions at tunnel entrance under high-traffic-flow condition.Under such condition,it is recommended not to use a fixed speed limit as a management measure at the tunnel entrance,but open a special lane for light-duty vehicles in front of the tunnel entrance or restrict heavy vehicles(such as trucks)during peak periods.This model can effectively evaluate the risk of rear-end collisions at the tunnel entrance,provide a theoretical basis for the improvement of managing measures,and ensure the safe operation of the tunnel.