平面信号控制交叉口有轨电车与机动车交通冲突风险评价模型

Risk assessment model of traffic conflict between tram and vehicle at signalized intersections

为改善平面信号控制交叉口有轨电车运营安全水平,基于交通冲突理论,建立考虑交通流状态条件下有轨电车与机动车转弯发生交叉冲突的概率公式,并以有轨电车和机动车的运行速度、速度差、减速度、间距等物理参数提出交叉冲突严重程度表征指标,建立交通冲突风险评价模型;基于上海市松江区有轨电车T1线某平面交叉口进行案例分析。结果表明:调整信号相位可一定程度改善交叉冲突发生的可能性;有轨电车与机动车行车轨迹形成的矩形区域可作为交叉冲突风险分析区域,以轨迹疏密程度划分为3个子区域,在最容易发生冲突的风险区域I可采取路面限速、特殊标线、反光道钉、贴地警示灯等设施降低交通冲突严重程度。研究结果可为有轨电车通行路口交通安全设计方法提供理论模型支撑。

In order to improve the operational safety of trams at signalized intersections,based on the traffic conflict theory,the probability formula of cross-conflict between trams and vehicles was established under the traffic flow condition,the characterization index of cross-conflict severity and the traffic conflict risk evaluation model were established based on the physical parameters such as the running speed,speed difference,deceleration and spacing of trams and motor vehicles.Based on the analysis of a signalized intersection on T1 line in Songjiang District of Shanghai,it was concluded that adjusting the signal phase could improve the possibility of cross-conflict to some extent.The rectangular area formed by the trajectory lines of trams and vehicles can be used as a cross-conflict risk analysis area which can be divided into three sub-areas according to the density of the trajectory.In the risk area I where conflicts were most likely to occur,road speed limits,special markings,reflective road studs,ground warning lights and other facilities could be used to reduce the severity of traffic conflicts.The research results can provide a theoretical model basis for the engineering application of traffic safety design at the intersection of trams.