随机边界元法及其在水工结构可靠度分析中的应用  

Stochastic Boundary Element Method with Application for Hydraulic Structural Reliability

作　　者：张明[1] 麦家煊[1] 吴清高[1] 

机构地区：[1]清华大学水利水电工程系,北京100084

出　　处：《水力发电学报》2002年第E01期46-53,共8页Journal of Hydroelectric Engineering

摘　　要：边界元法比较适用于复杂结构及大体积结构问题 ,计算量小而精度较高。本文针对一次二阶矩方法的计算特点 ,采用对基本随机变量求偏导数的方法 ,以确定性边界积分方程为基础分别建立零阶式和一阶式随机边界积分方程 ,并对此随机边界积分方程作了数值处理 ,编制了计算程序。作为应用 ,以该法作为重力坝应力分析方法 ,用JC法计算可靠度 ,对重力坝的强度可靠度和沿坝基面抗滑稳定可靠度作了分析 ,研究了岩基刚度、基本随机变量离散性的影响。计算分析结果显示 ,随机边界元法能更好地反映水工结构的随机应力应变场 ,从而使反映水工结构的各种工程可靠度指标更符合实际工程状况。Boundary element method is suitable for the problems of complex structure and large volume and possesses the advantages of few and accurate computation.Considering the property of first order second moment method,we established the zero order and first order stochastic boundary integral equations on the basis of deteministic two dimensional static elastic boundary integral equations by deriving the partial derivatives of basic random variables.We completed a stochastic boundary element program after treating with the equations numerically.As the application of the method,the strength reliability and the stability reliability of a concrete gravity dam were analyzed in detail with the stochastic boundary element method applied to get the stress field and JC method used to evaluate reliability.In the reliability computation,the effects of the stiffness of rock foundation and the variation of basic variables are considered.The numerical results show that the method presented in the paper is fairly conducive to the more accurate reliability computation of structures in hydraulic engineering.

关 键 词：可靠度 一次二阶矩法 随机边界元 重力坝 水工结构 

分 类 号：TV31[水利工程—水工结构工程]