随机结构失效演化与体系可靠度分析的自适应动态约界法  

Adaptive dynamic bounding method for failure evolution and system reliability analysis of stochastic structures

作　　者：刘娇 杨绿峰 余波[3] Liu Jiao;Yang Lvfeng;Yu Bo(Department of Management Science and Engineering,Guangxi University of Finance and Economics,Nanning 530007,China;Department of Housing and Urban-Rural Development,Guangxi Autonomous Zhuang Region,Nanning 530028,China;Key Laboratory of Disaster Prevention and Structural Safety of China Ministry of Education,School of Civil Engineering and Architecture,Guangxi University,Nanning 530004,China)

机构地区：[1]广西财经学院管理科学与工程学院,广西南宁530007 [2]广西壮族自治区住房和城乡建设厅,广西南宁530028 [3]广西大学土木建筑工程学院,工程防灾与结构安全教育部重点实验室,广西南宁530004

出　　处：《建筑科学》2024年第11期113-121,共9页Building Science

基　　金：广西科技基地和人才专项(桂科AD20238038);广西高校中青年教师科研基础能力提升项目(2020KY16022);广西财经学院博士科研启动金项目(BS2019047);统计学广西一流学科建设项目(智慧城市大数据统计分析与应用方向)。

摘　　要：结合动态约界策略和当量正态化原理,提出了一种适用于含非正态相关随机变量的随机结构失效演化和体系可靠度分析的自适应动态约界法。首先基于失效概率均匀度和基准可靠指标,建立了随机结构失效演化分析的自适应动态约界阈值,从而可以高效准确地识别关键候选失效元件,实现随机结构失效演化分析的自适应动态分枝和约界,兼顾主要失效路径识别的精度和效率;然后根据当量正态化原理和正交变换,将相关的非正态随机变量变换成独立的正态分布随机变量,从而将传统的体系可靠度分析方法从正态随机变量空间拓展到非正态随机变量空间。分析表明,基于自适应动态约界阈值不仅能够全面考虑结构体系中元件失效概率的分布状况,而且可以考虑随机变量分布类型对约界阈值的影响,从而可以避免遗漏主要失效路径,克服传统方法主要依靠工程经验确定约界阈值所存在的缺陷;外荷载和抗力的分布类型、相关性和变异性对随机结构的失效演化历程、主要失效路径和体系可靠指标均具有显著影响,且抗力的影响更为显著。An adaptive dynamic bounding method for failure evolution and system reliability analysis of stochastic structures that involves correlated non-normal random variables is proposed by combining the dynamic bounding strategy with the equivalent normalization principle.Firstly,adaptive dynamic bounding threshold for failure evolution analysis is proposed based on the uniformity of failure probability and the reference reliability index,which provides an efficient and accurate branch and bound technique for failure evolution analysis of stochastic structures.Then system reliability analysis method of stochastic structures in the normal random variable space is expanded to the non-normal variable space,by translating the correlated non-normal variables into the independent normal random variables based on the equivalent normalization principle and orthogonal transformation.Analysis results show that adaptive dynamic bounding threshold not only can consider the distribution of the failure probability,but also can consider the influence of distribution type of random variable,then it overcomes the disadvantages of traditional methods that depends on the engineering experience.Distribution type,correlation and variability of both external load and resistance,especially the resistance,have a significant influence on the failure evolution process,dominate failure path and system reliability index of stochastic structures.

关 键 词：随机性 失效演化 体系可靠度 非正态 自适应 动态约界阈值 

分 类 号：TU375.4[建筑科学—结构工程]