不对称交通流交叉口信号控制优化模型

Signal Control Optimization Model of Asymmetric Traffic Flow Intersection

交通流的潮汐特性与平面交叉口车流量分布不均匀性,易导致车道一方向车辆较多,产生堵塞,另一方向车道空放,浪费时间及道路资源。针对不对称交通流的特性,提出不对称交通流的信号相位选择模型与交叉口信号配时模型。首先分类讨论不同情况下不对称交通流相位方案;其次在NEMA相位结构的基础上调整webster信号配时计算方法,使得到的方案更加贴合道路实际情况;最后,通过VISSIM软件对优化后交叉口进行仿真。优化结果表明:与优化前相比,交叉口车辆行程总时间下降了12.7%,交叉口进口道排队长度下降了27.7%,延误下降了23.8%。因此,提出的优化模型能够提升不对称交通流交叉口的资源利用效果,降低信号周期绿灯时间的浪费,提升信号交叉口车辆通行效率。

Due to the tidal characteristics of traffic flow and the uneven distribution of traffic flow at grade intersections,it is easy to cause more vehicles in one direction of the lane,resulting in congestion,and the lane in the other direction is empty,wasting time and road resources.According to the characteristics of asymmetric traffic flow,this paper puts forward the signal phase selection model and intersection signal timing model of asymmetric traffic flow.Firstly,the phase schemes of asymmetric traffic flow under different conditions are discussed;secondly,the webster signal timing calculation scheme is adjusted based on the NEMA phase structure to make the obtained scheme more suitable for the actual road situation.Finally,the optimized intersection is simulated through VISSIM software.The optimization results show that in comparison with the traffic status before optimization,the total vehicle travel time at the intersection is reduced by 12.7%,the queue length at the entrance of the intersection is reduced by 27.7%,and the delay is reduced by 23.8%.Therefore,the optimization model proposed in this paper can improve the resource utilization effect of intersections,reduce the waste of green light time in signals,and then improve the vehicle traffic efficiency of signalized intersections.