摘要
分析了结构系统可靠度计算与多维正态积分之间的转化关系,以及原有的用于多维正态积分计算的条件边缘乘积法的不足之处,从条件正态分位数计算和相关系数矩阵修正两方面给出改进措施,形成一种改进的条件边缘乘积法。该方法采用数值积分方法进行二维正态分布函数的计算,提高原有方法中条件正态分位数计算的精度,并在此基础上对各相关系数矩阵进行修正,从而有效提高了原有方法在串联系统可靠度计算中的精度。同时,将这一改进方法与单失效模式下的结构可靠度显式迭代算法相结合,提出从单元到系统的结构系统可靠度分析流程。数值算例表明了这一改进方法的有效性和实用性。
The relationship between structural-system reliability evaluation and multi-normal integrals is analyzed,and the deficiency of the original Product of a Conditional Marginal（PCM） method for multi-normal integrals is pointed out.An improved PCM method adopting new measures for the calculations of conditional normal fractile and coefficient matrices is presented.The improved method firstly takes a numerical integration approach for the solution of bivariate normal distribution problems,which improves precisions of the fractile.Then,it updates the corresponding coefficient matrices,based on the precise fractile.It thus efficiently overcomes the inaccuracy of the original PCM method especially being used for the reliability evaluation of a series system.It also presents the details on how to implement the improved PCM method together with the explicit iteration algorithm,which is very efficient for element reliability evaluations.The availability and practicability of this improved PCM method is illustrated through two examples finally.
出处
《工程力学》
EI
CSCD
北大核心
2012年第10期321-326,共6页
Engineering Mechanics
基金
国防基础科研项目(D0920060310)
国防技术基础项目(Z092009B001)
关键词
结构系统可靠度
条件概率
多维正态积分
条件边缘乘积法
条件正态分位数
structural system reliability
conditional probability
multi-normal integrals
product of conditional marginal method
conditional normal fractile
