基于路侧事故判别的公路平曲线车速限制研究

Speed Limit in Curving Sections of Highway Based on Roadside Accidents Discriminant Analysis

车速是导致公路平曲线路段路侧事故频发的关键因素,为降低路侧事故率,需进行车速限制研究.选取8个路侧事故风险指标进行PC-crash仿真试验,共收集12800条数据.采用路径分析方法筛选得到显著性风险指标,将其纳入贝叶斯逐步判别分析中,构建对应不同车型的路侧事故判别函数,提出对应不同道路几何设计要素的最高安全车速计算模型.结果显示:显著性风险指标对路侧事故影响程度,由大到小依次为车速、圆曲线半径、车型、路面附着系数、路肩宽度、纵坡坡度和超高横坡度;道路线形条件越好,保证不发生路侧事故的最高安全限速值越大;在相同道路设计指标下,小型客车最高限速值大于货车最高限速值.

Speed is the key factor that leads to frequent roadside accidents in curving sections of highway.In order to reduce the roadside accidents occurrence,the research on speed limit is essential.In this paper,8 roadside accidents risk indicators were selected for PC-crash simulation test,and a total of 12800 data was collected.Path analysis was adopted to screen and obtain significant risk indicators.By incorporating the above significance risk indicators into Bayesian stepwise discriminant analysis,the roadside accidents discriminant functions corresponding to different vehicle types were constructed.Finally,the calculation models of maximum safe vehicle speed corresponding to different road geometric design characteristics were proposed.The study results show that:The significant risk indicators have the following order of influence on roadside accidents,such as vehicle speed,horizontal radius,vehicle type,adhesion coefficient,shoulder width,longitudinal slope and superelevation slope;The better the alignment condition of the road,the greater the maximum safe speed limit to ensure no occurrence of roadside accidents;Under the same road design condition,the maximum speed limit value of car is larger than that of truck.