Research On Time-varying Route Selection Model For Urban Hazardous Material Transportation

With physical chemical or biological properties, hazardous materials tend to leak, ignite or explode etc. during its production, storage and transportation. Those disasters do a lot of harm to the surrounding people, environment and property. Along with the rapid development of global economy, as an important industrial byproducts and consumer goods, hazardous material in circulation grows rapidly worldwide.A larger transportation volume follows the more frequent hazardous materials transportation accidents. Differing from the general traffic accidents, the hazardous materials accidents will cause destructive and harmful disasters such as leakage, radiation, explosion and pollution etc. Hazardous materials are threatening the environment and human beings continuously.When choosing the hazardous materials transport routes, we should consider traffic cost and population risk etc. In this way, traditional simple target turns into multi-target in the transport routes. Besides, the complicated and changeable urban environment and the time factor's effect on the traffic cost and risk add the time change property to the route selection.With a bright future for application, the research on the time factor-affected optimal multi-target route helps to resolve resource shortage, traffic congestion and protect human and ecological environmental system etc. in terms of the sustainable development of society and economy.Therefore, the scientific technologies are badly needed to optimize every unit of hazardous materials transportation and safeguard public interest and social security. The route planning of hazardous materials transportation in China is now supervised by transportation administration departments and worked out by private transportation enterprises. In fact, it is the driver that selects the shortest route according to his experience for reducing oil wear and time of transportation. However, other influencing factors are neglected which potentially threatens the public security. The irrational transportation route selection frequently leads to terrible accidents these days.With rich graphic and symbolic expressions and powerful space analytical function, GIS platform is inclined to used to analyze routes and assist the decision makers for route planning. Nowadays, GIS has been used abroad to analyze all kinds of risks, meanwhile many experts in China have proposed that the optimal transportation route analysis based on GIS platform is an inevitable trend in hazardous materials transportation route analysis.After summarizing countless related literary works, this thesis reviews the achievements at home and abroad in risk analysis and route selection and identifies the current deficient research on risk and route selection during hazardous materials transportation.On this basis, the thesis defines the notion of risk and technology route which deals with arc and node, makes in-depth analysis on all kinds of factors and risks affecting hazardous materials urban transportation, adopts multi-target planning strategy and applies many risk evaluation methods to systematic research on hazardous materials urban road transportation. The research mainly concerns the how time factor affects hazardous materials transportation route selection and accordingly builds hazardous materials transportation multi-objective optimal route selection models during different periods of time under time-varying condition. The thesis classifies and processes the available data, analyzes and sets the spatial data on ArcGIS platform and establishes the organization of transport network spatial data based on the routes. Next, in terms of different periods of time, buffer and overlay analyses etc. are adopted to analyze the entity factor affected by time factors in the transport network and update its space and data attributes correspondingly.Network Analyst module in ArcMap calculates the optimal route from the beginning to the end during different periods of time and its integrated expense, distance and the number and grade of the passing hazardous areas. For the route analysis and evaluation, the thesis compares the obtained transport route during different periods of time with the shortest route and verifies the rationality of the selected route.In the end, the thesis summarizes the whole research, brings about the major conclusions and looks forward the limitations and further effort.