基于实测数据的出口车道左转交叉口饱和流率修正

为了准确计算出口车道左转交叉口的通行效率,基于实测数据,对该类型交叉口饱和流率进行了研究。研究调查了邯郸市的3个设置有出口道左转的交叉口和1个具有相似规模的常规交叉口,并根据左转车道位置,将调查数据分为5组,包括出口车道左转交叉口的进口左转车道、2条出口左转车道、预信号处左转车道以及常规交叉口进口左转车道。通过将各组出口车道左转交叉口饱和流率与常规交叉口进行对比,证实了出口车道左转这种控制方法对交叉口主停车线和预停车线饱和流率均存在显著影响。在此基础上,考虑车辆滞留、驾驶员非正常驾驶行为、车道利用率、多左转车道和有效绿灯时间等因素,运用概率论及数理统计,分别对主、预停车线建立了出口车道左转控制对车道饱和流率的修正模型。并将模型计算结果与实际调查结果进行比较,对模型进行了检验,主、预停车线处饱和流率估算平均误差分别为1.6%和1.5%。研究表明,出口车道左转控制方法虽然能提高交叉口整体通行能力,但对饱和流率会造成一定负面影响,降低预停车线处和主停车线处车道饱和流率分别为19.4%和23.1%。预停车线处主要影响因素是驾驶员非正常驾驶,主停车线处主要影响因素是车道利用和多左转相互干扰。

Intersection capacity based on driver's visual characteristics

In order to reflect the influence of the drivers＇ characteristic differences on intersection capacity under a mixed traffic flow, a driver correction coefficient for the intersection capacity calculation according to the driver＇s visual characteristics is proposed. First, the parameters of the driver＇s visual characteristics at some real roads, including gaze fixation distribution, mean fixation duration, visual angle distribution and some other parameters at intersections, are collected. Then, the relationship between the traffic flow rate at intersections and the parameters of driver eye movements are established. The analytical results indicate that when the traffic flow is unsaturated, the parameters of driver eye movements change relatively little; however, when the traffic flow is saturated, the parameters of driver eye movements change drastically. Finally, the saturation-flow-rate model is modified according to the parameters of driver eye movements; thus, a capacity model of intersections considering the driver＇s visual characteristics is obtained.