Benefit Risk Assessment Of Reservoir Danger Removal And Reinforcement

At present China have the most reservoirs in the world. Reservoir has played significant benefits in flood control, irrigation, water supply and power generation.According to recent statistical data, there are about 100 defect reservoirs among the more than 350 large reservoirs in water system management. One-third of medium and small reservoirs are defect reservoirs, and the number is more than 20,000. Defect reservoir has become the weakest section in the field of dam safety management, so our government increases investment in reinforcement in recent years. With big investment and a long cycle, danger removal and reinforcement need the benefit analysis.The construction and management process of reinforcement inevitably affected by many uncertain factors, for example, flood-control benefit affected by the flood frequency, the development level of protection area. Compared with expected value, all of these random factors can make errors of the benefits, which means the benefit risk exists. The traditional economic evaluations which use the mean of the benefit and expense, do not consider the influence of randomness.In the paper, risk analysis theory is applied to the benefit risk assessment of reservoir danger removal and reinforcement. Considering randomness and correlation of the influence factors, build computing function of the reinforcement benefit, and establish the benefit risk assessment model of reservoir danger removal and reinforcement. All the work will provide more objective and intuitive basis for reinforcement decision-making.This paper mainly includes the following contents:(1) Recall the traditional method of economic evaluation for hydraulic engineering,then apply the method to reinforcement engineering. (2) Introduce the risk analysis theory and application in hydraulic engineering, summarize the existing risk assessment methods.(3) Establish the benefit-risk assessment model of reservoir reinforcement. Using Monte Carlo method to simulate the benefit and expense variables, get the probability distribution of each variable.(4) Take into account the correlation between variables, Nataf transformation method is applied to solve the reinforcement project benefit-risk rate.(5) Apply the benefit-risk assessment model to Xiaozhuangzi reservoir reinforcement project. Analyze the uncertainty of variables and carry out the benefit risk assessment.