Flood Control Ability And Risk Research Of Nanning Flood Control Engineering System

This paper adopted reservoir-embankment flood control engineering system of Nanning as the research object. Considered randomness of incoming flood and flood random combination, used the Monte Carlo method and seasonal AR (1) model, calculated Nanning flood control engineering system’s flood control risk rate, used allowing risk analysis method to judge flood control ability of Nanning.The study shows that:The article adopted the seasonal AR (1) model to simulate incoming flood of Baise reservoir and interval flood. The relative errors of simulated and measured parameters within5%and that can better reflect statistical features of measured samples. Combined simulation of flood and Nanning control sections of design flood frequency according to a certain rule, Nanning flood control engineering system joint operation, got system risk rate. The two schemes calculation result showed:just considering risk of overtopping and overflow, there is no risk when Nanning section meets with50～250year flood; When Nanning section meets with300year flood and above, the system risk rate is increased. While flood frequency is smaller, the risk rate tends to1.The risk rate of first scheme is greater than the second. Because flood combination of first scheme, flood comes mainly from interval and flood control capacity of Laokou reservoir is small, which is disadvantage to flood control of Nanning. At the same time, the result showed risk rate calculation results of first scheme is more closed to engineering practice, flood combination of this scheme is basic conformed to the characteristics of Nanning flood. Then used loss of life risk as indicator, and adopted allowed risk analysis method to calculate risk of the system. Only considering risk of overtopping and overflow, when Nanning section meets with300year flood, the system risk is far more above tolerance risk. Synthetic judgment, Nanning flood control capacity basically reaches standard of250year flood, which slightly larger than the standard of200year flood in the planning of Nanning.