Optimization And Simulation Research Of Signal Timing At Urban Plane Junction

As accumulation and dissipation of city road, intersections are the control points of orderly organization of various transports and an indispensable part of city road, also, as the "bottleneck" and "throat" zone of city road, which has played a very important role in road network. Therefore, doing research on the signal timing of road intersection will have vital significance for solving the problem of traffic jams, improving city intersection traffic capacity and enhancing the utilization rate of road resource.Firstly, one multi objective optimization model is proposed based on delay, queue and the traffic capacity. The model divides target function into2layers:layer1selects average delay, average queue and capacity index to optimize the city intersection traffic efficiency; layer2selects vehicle delay standard deviation to improve the stability of signal control. We then establish the relationship between target weight and flow fluctuation amplitude according to research on the city road intersection under different traffic state environment and solve it by genetic algorithms. Secondly, simulation model of city road intersection is established, which can reproduce the city road operation and provide accurate and scientific basis for traffic control. Finally, this paper selects Beijing North Taiping bridge intersection as an example. Based on Vissim simulation platform, we builds North Taiping bridge microscopic simulation model according to the data obtained in survey and simulates the traffic operation. Also, we optimize and evaluate the existing signal scheme by applying the proposed multi objective optimization model based on delay, queue and capacity.The intersection signal timing optimization model takes into account connection and constraints among delays, queue and traffic capacity at the intersection, compared with others, robustness of this model has been improved and the stability of the timing program is strengthen.