Risk Assessment of Dam Overtopping Based on The Extended Three-parameter Distribution and Stochastic Differential Equation

Abstract

For earth and rockfill dam, overtopping is intolerable especially for those dams where cascade hydropower stations exist in the river basin. The flood safety of control reservoir directly relates to the safety of the dam. It is necessary to carry out an accurate analysis for flood risk. Based on the extended three-parameter Burr XII distribution of the maximum reservoir inflow design flood computation, the results are larger than the design standard using analysis method which is also based on Person O distribution. The flood risk analysis of uncertainty factors is considered based on the stochastic differential equation. Combination of these two methods, dam overtopping risk is calculated, greater risk is obtained than the traditional JC method, and the conclusion is much more rational. When determining the crest elevation in water conservancy engineering, the design of dam safety evaluation and risk analysis should be considered using more uncertain factors involved, and the new method is more feasible and reasonable than traditional methods.