Research On Decision-Making Principle And Method Of Construction Diversion Planning

The construction diversion is one of the most important processes in hydraulic engineering. It is difficult for people to select the best one, because it is influenced by a great deal of factors, such as technical, economical, safe, social problems. To support decision-making, the construction diversion hereinafter is studied in this paper.In the first chapter, the correlative research results are summarized, and the techniques including GIS (Geographic Information System), DSS (Decision Support System), VISC (Visualization in Scientific Computing), ANN (Artificial Neural Network), Simulation technique, which will be used in this paper, are introduced. Then, the questions are introduced, and the works that will be done in this paper are listed.In chapter 2, the construction diversion system concept and the system risk concept are defined basing on the Systems Engineering principle. The construction diversion tandem system, which is fit for describing the complexity and dynamic of system, is established. Then, the uncertainty factors of construction diversion system are concluded in detail. In particular, it is pointed out that construction altitude is an important variable to study. Lastly, the risk model of construction diversion tandem system and the synthetic risk model of construction diversion system are set up.In chapter 3, a simulation method to calculate the system risk is introduced, which is synthesis of the M-C (Monte-Carlo) method and the disperse system simulation method. The AR (Autoregressive) model to simulate the flood process, and the ANN model to simulate the flux faculty of the water diversion tunnel are used. An example that shows this method is available.The decision making of the construction diversion scheme is a complex problem, which is relating to economy, technology, and safety. So in charter 4, with the help of the expert investigation method and IAHP (Improved Analytic Hierarchy Process), a multi-criteria group decision-making method is introduced, which makes it easy to make decision in the construction diversion scheme. An example given proves that the method present in the paper is feasible. To help the managers to recognize the decision object, VADSS (Visualization Assistant Decision Support System) is defined. It is different form ordinary DSS in the way of the information expression. To use it in the construction diversion, a CDVADSS (Construction Diversion Visualization Assistant Decision Support System) is set up. Its functions include visual information of geography, geology and construction and the visual analysis method of dynamic information. It works for the engineering.In chapter 6, the grazing boundary of riprap and riverbed is analyzed. The opposite expose level and the inclination amount are introduced to describe the physical character of riprap. Then, a stability model is established according to the mechanism of the riprap lost stability. And the stability of one closure engineering is calculated with the support of the stochastic simulation method. The relationship of the stability and the flow rate and grain size is summarized.In chapter 7, the closure risk mechanism is analyzed, and a closure risk model is worked out. The calculation method is analyzed with the help of an engineering example.