Research On Urban Traffic Congestion Evacuation Control Method

With the development of urbanization around the world, congestion has occurred increasingly and frequently on traffic networks. The urban traffic congestion has eventually transfer to huge loss at social, economic, environmental and human-healthy costs.Currently, while the intelligence transportation control systems are prone to fail due to the scarcity of pertinent solution for congestion evacuation and control strategy, especially in the existing control system such as SCATS, SCOOT, RHODES etc merely suited to the congestion-free state. Through studying these typical control system,I found that the existing traffic control systems in congestion evacuation control show some deficiencies as the following:first, no deep insight analysis of the relationship among congested flows, but only rely on some numerical index to determine the congestion degree, and ignore the significance of judging the real-time comprehensive congested evacuation priority according to the global congested degree influenced by congested flows; second, no optimization between congestion evacuation control strategy and control parameters calculated by the information of congestion evacuation priority.In this paper, we analyzed relationship between congested flows in the traffic network through waiting relation model. and based on which, we determined the congestion evacuation priority factors, Then, in the light of existing numerical index and priority impact factor, we proposed a kind of method for traffic congestion evacuation priority determination, using congestion impact factors as input as well as BP neural network model as area-traffic congestion judge evacuation priority. Finally, considering the congestion evacuation priority as parameters for establishing congestion evacuation and control strategy, a signal control method is proposed based on congestion evacuation priorities, which utilize evacuation priorities to optimize the phase sequences and to calculate green time.Finally, through exemplifying the regional network congestion on Dalian Xian Road using the congestion control method, we conducted the simulation to evacuate the evacuation of the heavy traffic congestion, in VISSIM simulation platform. The results demonstrate the efficiency of this method.