Study Of The Emergency Evacuation Traffic Control Technology Under The Condition Of Major Disasters

In recent years, influenced by the climatic factors such as global warming and so on, the environment is becoming unfriendly. A large amount of innocent lives were engulfed by earthquake, tsunami and hard rain. Terrorist attack, violent riots, nuclear radiation put many helpless people under the shadow of fear. In addition, the acceleration of urbanization increases the aggregation degree of the means of livelihood and production, which enlarges the impact of the disasters. The urban road network is generally regarded as the lifeline of disaster prevention and reduction. However, traffic congestion makes it unstable, especially in the condition that a disaster happens. The city's fragile urges for the development of urban disaster emergency management.With the support of the state high technology research and development task (863 plan) Traffic organization security technology in the condition of Major disaster and Study of the obtaining technology of abnormal state information when the road network is in the abnormal condition, the dissertation focuses on the key technology in urban disaster emergency management, as following are the achievements.(1) The evacuation travel demand estimation technology. Firstly, the dissertation depicts the definition of disasters according to comparing the different characters of emergency, disaster and catastrophes. The range of disasters is bounded as well. Secondly, the disasters are classified into and predictive by means of the impact. In the mean, the impact of the disasters imposed to urban transportation system is introduced according to traffic facilities, traffic flow as well as road network reliability three aspects. Thirdly, based on the logistic regression and response curve, two evacuation travel demand estimation models are developed, used in the condition of predictive and anticipative happening, respectively.(2) The evacuation traffic control strategy.Aiming at the domestic drawback in the disaster emergency management, the dissertation proposes an evacuation travel mode that transit is in the primary part and car is in the subordinate part. Then, the strategies guaranteeing the transit's priority are presented in time and space degree respectively.In terms of space, bus lane is arranged in the lateral of links. In the intersection, the priority is achieved by means of taking over the right-hand oriented lanes.In terms of time, a transit actuated control strategy is addressed in a fixed-timing signalized intersection. The strategy is comprised by the calculation of maximum green time, minimum green time, cycle time, phrase basic green time. In the end, according to the arrival moment and the impact to the other evacuation cars, different transit actuated control strategies are presented. In the mean time, the actuated thresholds are determined(TV1,TV2,TV3).