城市混行进口道通行能力计算方法研究

Traffic Capacity Calculation Method of Urban Mixed Entrance Lane

针对城市道路交通混行现象严重问题,通过对城市道路信号控制交叉口交通运行特征进行调查分析,对直左车辆混行和小型汽车与公交车混行的进口道饱和车头时距和通行能力计算方法进行研究。为了得到城市交叉口混行进口道道路通行能力计算模型,首先对城市道路信号控制交叉口交通进行调查和数据收集,并对混合进口道车头时距进行特征分析,获取进口道车队运行特征参数;然后,分别建立直左混行车头时距和公交车小汽车混行车头时距分析模型;再次,建立基于转向比例和公交车比例的混合进口道通行能力计算方法;最后,结合案例进行通行能力、公交车比例和转弯比例关系分析。研究结果表明:笔者提出方法计算得到早晚高峰结果与实测值误差分别为1.5%、6.95%,较CJJ 37—1990《城市道路设计规范》法和HCM法计算值误差小,大大提高了计算结果的精度,可以为交叉口的控制和管理提供依据。

In view of the serious problem of mixed traffic on urban roads,the calculation method of saturated headway and capacity of the entrance road with mixed straight left vehicles and mixed small vehicles and buses was studied,through the investigation and analysis of the traffic operation characteristics of signal controlled intersection on urban road.In order to get the traffic capacity calculation model of the mixed entrance lane of urban intersection,firstly,the traffic investigation and data collection of urban road signal controlled intersection were carried out;at the same time,the characteristic analysis of the headway of the mixed entrance lane was carried out to obtain the characteristic parameters of the fleet on entrance lane.Secondly,the analysis models of the mixed headway of the straight left vehicles and the bus and car were established respectively.Thirdly,the calculation method of the capacity of the mixed entrance lane based on turn ratio and bus ratio was established.Finally,the relationship among capacity,bus ratio and turn ratio was analyzed,combining with case study.The research results show that:the error between the morning and evening peak results calculated by the proposed method and the measured values is 1.5%and 6.95%respectively,which is smaller than that calculated by methods of CJJ 37-1990“Code for Design of Urban Roads”and“Highway Capacity Manual”.The proposed method greatly improves the accuracy of the calculation results and may provide basis for the control and management of intersections.