力学与实践 ›› 2010, Vol. 32 ›› Issue (2): 71-75.DOI: 10.6052/1000-0879-2009-337

• 应用研究 • 上一篇    下一篇

基本变量对失效概率重要性测度分析的新方法

李贵杰 吕震宙 宋述芳   

  1. 西北工业大学航空学院 西北工业大学航空学院
  • 收稿日期:2009-08-31 修回日期:2009-12-08 出版日期:2010-04-08 发布日期:2010-04-08

A NEW METHOD FOR ANALYZING IMPORTANCE MEASURE OF BASIC VARIABLE EFFECT ON FAILURE PROBABILITY

Gui-Jie LI zhenzhou lu   

  • Received:2009-08-31 Revised:2009-12-08 Online:2010-04-08 Published:2010-04-08

摘要: 在研究矩独立基本变量对响应分布影响的重要性测度的基础上,定义了基本变量对失效概率 的重要性测度. 基本变量对失效概率的重要性测度可以直接全面地给出基本变量对结构安全 影响的重要程度,因而该重要性测度将更具有工程指导作用. 文中分析了所定义基本变量对 失效概率影响重要性测度的基本性质,并基于鞍点线抽样在求解可靠度时不受随机变量分布 形式的限制及其效率和精度较高的优点,提出了求解该重要性测度的鞍点线抽样方法.

关键词: 鞍点逼近 线抽样 灵敏度分析 矩独立 重要性测度 失效概率

Abstract: From the moment-independent importance measure of basic variable effect on response distribution, an importance measure is defined to describe the effect of basic variable on failure probability. Compared with the importance measure of the basic variable effect on the response distribution, this measure can directly provide the global effect of the variables on the structural safety, so can provide more guidance in engineering design than the former. The basic properties of the importance measure of the basic variable effect on the failure probability are discussed in this paper. Since the saddlepoint based line sampling method is independent of the distribution types of the random variables, and has the advantages of high accuracy and efficiency, this method is employed to estimate the defined importance measure.

Key words: Saddlepoint approximation, Line sampling, Sensitivity analysis, Moment independent, Importance measure, Failure probability