The Coordination Control Of Urban Expressway Exit Ramp And Joint Intersection

Serious traffic congestion often occurs between expressway exit ramp and the join intersection area. Once the cohesive intersection can’t shunt well, the join between expressway exit ramp and the intersection will be congestion, the ramp vehicles will backlog queue within the ramp, and the expressway mainline traffic flow will be effected in a very short time. Based on the analysis of traffic organization and traffic characteristics on vehicle traffic impact, this paper designs the regional traffic signal coordination optimization timing, implements the exit ramp and join the coordinated control of intersection.Through introduces the imports of maximum queue constraint and red light, the minimum green light constraints, and combines the phase sequence optimization, green time prolonging and the side road green light interval release strategy, this paper establish the coordinated control model between expressway exit ramp and the intersection. At the end of each cycle, the imported vehicles queue length is judged. When there is a super-long queue, the phase sequence is optimized and its corresponding green time will be operated in advance. When green time of the key phase ended and the vehicle queen is long enough, then a unit green time is added. While the auxiliary road light operation is green signal, if the key import produce a long queen, the light skip to operate red signal for a period time to ensure that the ramp vehicles can timely out on travelling. The integrated use of these strategies can reduce or even prevent the import of road congestion, and improve the traffic efficiency of the region.VISSIM is used to build a virtual road segment based on the Wu Feng Kou expressway exit ramp cohesion Ding Mao bridge road intersection in ZhenJiang. According to the previous site survey traffic flow data, several different traffic flow scheme is designed. First, the influence of different traffic engineer design is simulated to evaluate the vehicle running. Then, the vehicle queue length of every imports of the intersection, average delay time of vehicles and the total intersection delay time is used to evaluate the validity of the new control model. The simulation results shows that, compared to other control ways, the new control model can decrease the queue length of each import within 100m successfully, and increase at least 13%for balanced degree of the delay time of imports, it also reduce the intersection total delay time over 10%, and effectively improve the traffic efficiency of the area.