高速公路单向双车道车辆群行车风险度量研究

Study on Driving Risk Measurement for Two-lane Freeway Vehicle Group

为了探讨局部车辆流的安全性及其对道路安全性的影响,从“车辆群”的角度研究了高速公路行车风险度量。提出了高速公路单向双车道“车辆群”范围的划分方法;分析了“车辆群”内可能存在的侧向碰撞、侧面刮擦、追尾碰撞等冲突类型,针对各冲突类型选取了“车辆群”风险度量的碰撞时间TTC和后侵入时间PET这2个指标,提出了双车道“车辆群”行车风险度量模型,并用VISSIM对模型进行了仿真分析。结果表明:由于车辆换道的影响,双车道“车辆群”并不仅仅是两个单车道相邻车辆的对应合并;对道路上的车辆流进行“车辆群”划分后再评估车辆的行车风险,可以缩小道路上潜在危险区域的排查范围,提高高速公路行车风险识别效率;出现冲突风险警告的“车辆群”内车辆速度的偏差程度远远大于其他的“车辆群”,从而验证了模型的有效性。

To find out how local vehicle flow influences road safety,a driving risk measurement was done for two-lane freeway vehicles by means of vehicle group.A method for the range of vehicle-group was proposed to analyze such possible conflicts as lateral collision,side scraping,rear-end collision.Reasonable measurement index for each was selected for the driving-risk measurement model of the two-lane highway based on time-to-collision(TTC)and post encroachment time(PET).The model s feasibility was finally confirmed with a case study of VISSIM simulation.The results show that,according to the vehicles lane-changing behaviors,the two-lane vehicle group is not just a merge of the opposite vehicles on a two-lane freeway,that evaluating its driving risk can shorten the check of the potential area,improve its risk identification,and that the risk warning for deviation of running speeds through velocity analysis is far greater than others,which proves the efficiency of the model.