The Research On Coordinated Control Strategy Of Urban Freeway On-ramp And Side Way’s Intersection

In recent years, with the continued growth of the vehicles, Freeway’s demand is increasing. The congestions of freeway are also increasingly, seriously affecting the efficiency of urban transport. Ramp control has optimized the freeway mainline traffic’s flow, but it does not consider the state of the side way’s traffic flow and the vehicles queue of ramp. When the freeway traffic flow increases, the queue length also increases, thus affecting the side way’s upstream intersection signal control. Roads intersection inappropriate signal control will affect the ramp traffic, resulting ramp generated at the long queues. So we should combine the ramp control with sideways intersection control as a whole. Hope to achieve a smooth transition of the vehicles on the freeway and urban roads, improve the efficiency of the urban road network.In this paper, we had studied the freeway’s bottleneck area. The coordinated control strategy of urban freeway on-ramp and side way’s intersection has been researched. The mainly work in this dissertation as follows:1、We take the side way into account, build a continuous flow ramp model with the more mature theory, and a coordinated control method had been proposed.2、In consideration of the complexity and nonlinear of the urban traffic, we analyzed the discrete dynamic behavior of the control strategy based on petri net theory and verified the feasibility of this algorithm by CPN Tools. Next we used MATLAB to do some data analysis.3、Using micro-simulation software VISSIM, we build an actual road network model, the west fourth ring road of Beijing. Then we carried out simulation on the algorithm:Fixed Time Control ALINEA Control and the Coordinated Control. Many meaningful data are given and we can use these date evaluate the effect. The experiment results show that that the coordination control has improved the traffic condition, such as delay time, queen length and so on. The control effect was notable and advanced the availability of urban road network.This dissertation is an exploration of the freeway and side way’s coordinated control, and hopes to provide a theoretical basis for the operation of urban freeway system.