Emergency Restoration Strategies For Post-Earthquake Road-Networks Based On Evacuation Behavior And Relief Distribution

Earthquakes are one of the most destructive types of natural disasters and often cause enormous damage to the road network of lifeline systems, causing heavy casualties and huge property losses. Therefore, to quickly restore the serviceability of lifeline systems of transportation by roadway repair and then take a scientific, rational and efficient disaster emergency resuce is very important for reduce disaster losses.The roadway network by repair can improve the supply capacity of road network, emergency resuce and evacuation efficiency, and all of these are affected by the evacuation behavioral. Therefore, it is very necessary to be considered them together to improve emergency resuce efficiency and cut down the losses caused by disaster. In this thesis, firstly, the mechanism of victims’ evacuation behavior is analyzed. Secondly, a framework for evaluating the vulnerability of roadway network is given. Thirdly, a bi-level programming and a multi-objective mixed integer programming for roadway repair based on evacuation behavior and emergency relief distribution are developed respectively and. Finally, there are some algorithms are designed and some numerical examples are abstracted to verify the reliability and validity of the models and algorithms.The detailed research contents are showed as follows:(1) To analyze the mechanism of victims’post-earthquake evacuation behavior. Some objective factors, such as, the trip puporse, travel tools, travel beginning time and so on, some internal factors, such as, the chang of psychological state, stress behavior mechanisms, risk reference and so on, and some external conditions, such as, home safety, social support and so on are analyzed at first. And then, how evacuation behavior to be affected by these factors has analyzed based on disaster-psychological and behavioral response model and cumulative prospect theory(2) Based on post-earthquake evacuation behavior to evaluate the roadway network vulnerability. According to the mechanism of post-earhquake evacuation behavior, an evaluated framework is established to measure the vulnerability of post-earthquake roadway network by the standard of travel time delay. A test is abstracted from ShiFang City, in WenChuan earthquake. And the test results showed that this model is more efficient and effective than network accessible evaluated model which is introduced in reference [127] and can supply a theory for making a scientifical repair strategy to improve the serviceability of realistic roadway network.(3) Based on post-earthquake evacuation behavior and emergency relief distribution to make a roadway restoration strategy. Due to the evacuation behavior, emergency relief disttibution and state of roadway network were influence with each other and would be changed with the roadway restoration. Therefore, a bi-level programming is developed, and the upper-level objective is to maximize the utility of roadway restoration and to minimize the total time for delivering emergency commodities and maximize the equity for allocating emergency commodities are taken as the lower-level objectives. A stable genetic algorithm is designed to solve the model. A test is abstracted from DeYang City, in WenChuan earthquake. And the test results showed that the roadway restoration can improve the supply capacity of roadway network to cut down the total time for delivering emergency commodities and victims’evacuating time, however, due to the mount of victims entered into roadway network, the roadway restoration efficiency was low.(4) Based on post-earthquake evacuation behavior and emergency relief distribution to make a roadway restoration strategy in the context of traffic control. In order to transfer the emergency commodities to affected area immediately, in addition to the evacuation behavior, roadway restoration and emergency relief distribution needed to consider, traffic control is also very important. Based on this, a multi-objective mixed integer programming is established to maximize the utility of roadway restoration, to minimize the interruption of traffic control, and to minimize the total time for delivering emergency commodities. A no-dominate sort genetic algorithm is designed to solve the model. A numerical example is abstracted from DeYang City, in WenChuan earthquake to verify the model’s realiabilty and efficiency. The numerical example results showed that the roadway restoration within traffic control is more efficiency than no traffic control which had calculated in Section 4.In summary, in this thesis, the mechanism of victims’evacuation behavior is analysed at first and then a evaluated model for measuring vulnerability of roadway network is estabilished and the results is come out. A bi-level programming and a multi-objective mixed integer programming for roadway restoration is based on evacuation behavior and emergency relief distribution are developed and the models reliability and effieciency have been verified by the numerical example in section 4 and 5 respectively, and therefore, we would be useful in practice.