The Research On Risk Evaluation And Control Method Of The Cost Of Railway Construction Based On D-S Evidence Theory

With the development of national economy,particularly in 2008, the international financial crisis and the demand for national stimulating domestic demand has brought unprecedented opportunities to the development of the construction of infrastructure facility, for example, roads, railways, aviation and other infrastructure facilities have a Leap-type development. However, with the increasingly fierce of market competition, seriously shrinking of profit margins and the management confusion brought about by the size expansion, it is placed in front of all workers that how to impose cost management, establish a cost risk evaluation model and take effective control measures to reduce construction costs, rise economic efficiency, enhance market competitiveness and ensure business has a continually, healthy, steady and harmonious development.In view of the railway construction project, in the paper, firstly determine the evaluating indicators. The author summarizes the associated risk factors of the cost of the domestic and foreign railway construction and determines its evaluating indicators from two aspects including both the technical risk and non-technical risk. In the process of determining the indicators, due to the complexity of railway construction project and the diversity of cost impact factors and so on, first of all, using the main component analysis to reduce the amount of the corresponding risk indicator factors makes the risk assessment to be more accurate and concise; secondly, establish a mapping relationship between the qualitative indicators and the risk, thus achieve an effective combination of qualitative and quantitative analysis.Secondly, establish a multi-level hierarchical evaluation model based on D-S evidential theory. In process of the model establishment, the author uses method of network analysis (ANP) to determine the evaluating indicators'weights of the cost risk. ANP method overcomes the defect of AHP method that it has a simple hierarchical structure and establishes a similar network structure, in which internal elements of each layer are able to depend on each other and the low-layer elements dominate the high-layer ones. In the synthesis of theory, in order to prevent the potential problem of exponential explosion, reduce the number of focal elements of mass function and realize the synthesis of D-S evidential theory effectively, with the actual situation of Shanghai-Nanjing Intercity Railway Construction Project, the author uses the approximate calculation method based on Bayes's D-S evidential theory, successfully verifies the effectiveness of the multi-level hierarchical evaluation model based on D-S evidential theory and provides theoretical basis for its risks'effective control.Finally, according to the cost risks'characteristics of railway construction project, the author makes a research on its cost risk control from three aspects, such as risk surveillance, risk pre-control management and risk aversion management. On the other hand, the author makes a comprehensive assessment research on the control effect of railway construction cost from two aspects, such as the static control effect research of railway construction cost based on weighted scoring method and the dynamic control effect research of railway construction cost based on fuzzy relative evaluation, in combination with the actual situation of Shanghai-Nanjing Intercity Railway Construction Project, inspects and evaluates the effectiveness of the two program.