LHS-MC方法在漫坝风险分析中的应用

Overtopping risk analysis using LHS-MC method

利用拉丁超立方抽样-蒙特卡罗方法(LHS-MC)评估了洪水和风浪作用下大坝的漫坝风险。采用LHS代替MC的随机抽样过程,生成洪峰流量和风速等随机变量样本。以大坝漫坝风险问题为例说明了LHS-MC方法的有效性。结果表明:LHS-MC方法可有效地提高运算效率,较少的抽样样本就能反映参数的概率分布,风险分析收敛快。考虑水库防洪调度规则,用水库调洪演算可得到水库最高调洪水位随机分布和洪水漫坝风险率。

This study develops a LHS-MC method to evaluate dam overtopping probability that accounts for the uncertainties arising from wind speed and peak flood,and examines the use of Latin hypercube sampling（LHS） as a tool for better efficiency of MC random sampling method.LHS is used to generate samples of peak flow rate and wind speed,especially for rare events.To demonstrate the validity and capability of the proposed method,an example of dam overtopping risk analysis is presented.Application in numerical examples shows that LHS is faster in convergence and more efficient than MC simulation.Reservoir routing that incorporates operation rules,wind setup and run-up,can generally be used to evaluate dam overtopping probability.