结构可靠度分析中的混合模拟法及应用

摘要

A hybrid simulation method based on Latin hypercube sampling (L HS ) and uniform design response surface method (LUH) was proposed aiming at reliability analysis problems of complex structure with multivariate random variables and implicit limit state function . The input variables with higher sensitivity factors were selected by LHS method and were treated sequentially as stochastic variables .The program of uniform design table with minimum L2‐deviation was compiled in software Matlab and the sample points for stochastic variables were selected according to the uniform design table .The structure failure probability was calculated by JC method during iterative process of constructing response surface equations .The feasibility of the hybrid simulation method was verified by two classical numerical examples for structural reliability analysis and one numerical example for structural reliability analysis of a continuous rigid frame bridge .Results show that the proposed method can accurately and efficiently solve the reliability analysis problems for the structure with multivariate random variables .%针对具有多维随机变量、隐式功能函数特点的复杂结构可靠度分析问题，结合拉丁超立方抽样（LHS）法与均匀设计响应面法，提出基于拉丁抽样均匀设计的混合模拟法。利用L HS法选取灵敏度较高的输入变量继续作为随机变量。通过M atlab语言编写L2‐偏差最小的均匀设计表程序，根据生成的均匀设计表选取随机变量的取样点，在构造响应面方程的迭代过程中利用JC法求解结构失效概率。通过2个经典可靠度算例和1个连续刚构桥可靠度算例验证了混合模拟法的适用性。研究结果表明，采用该方法可以精确、高效地求解具有多维随机变量的结构可靠度问题，提高计算效率。