Emergency Evacuation Model On Urban Traffic Network

After the emergency, it is important for preventing or decreasing casualties and avoiding a secondary disaster to evacuate the people who suffer from emergency to safe areas in time.However, the current domestic emergency management is still in its infancy stage. So, after the emergency occurred, for orderly implementation of traffic organization, and in order to provide the theoretical conditions and basis for follow-up proposing emergency evacuation organization methodology, it is necessary to make systematic and comprehensive study on emergency evacuation of city network, and establish evacuation optimization model and modeling system about emergency evacuation of city network.Based on the analysis of current situation of domestic and foreign research on urban traffic emergency evacuation, I have consulted a large number of documents about network optimization, dynamic traffic assignment, cell transmission model, traffic management and control and so on, and analyzed the characteristics of emergencies and existing management measures. On the basis of the study on evacuation characteristics and traffic demand properties, I have mainly undertook the following work:First, based on the cell transmission model (CTM), I have created a dynamic system optimum traffic assignment model (DSO) applicable to emergency evacuation on city network. In this model, I have creatively studied signal control intersection, and separately considered street, intersection, origin and destination. The model have overcome the disadvantage of that the conventional CTM only consider the road delay, but ignore the queuing delay in signal control intersection.Secondary, on the basis of CTM above, I have created a bi-level programming model applicable to emergency evacuation on city network. The model abstract the actual traffic management decision problem on evacuation to a bi-level programming model that includes a upper level problem and a certain number of lower levels problem. The upper level problem make use of DSO for path planning. The lower levels problem optimize the intersection's signal timing of city network. And then I have used Karush-Kuhn-Tucker method and genetic algorithm to solve the model.Last, on the basis of currently technology such as intelligent traffic, satellite navigation system, video monitoring technology, and telematics, I proposed the molding processes about emergency evacuation on city network. And the model are verified by an example. The results show that the model and algorithm could effectively improve the emergency evacuation efficiency on city network. In consequence, the study have laid a foundation for follow-up study, and it also provided a reference scheme for emergency evacuation.