摘要
为解决混合变量下的结构疲劳寿命分析问题,建立了同时含有概率、模糊、区间变量的结构疲劳寿命分析模型,采取对模型中的模糊变量取截集的方法,使模糊变量退化为相应的区间向量,相当于将问题化为仅含有随机变量和区间变量的结构疲劳寿命分析问题。依照概率和非概率寿命分析方法得到在截集水平α下的随机变量为自变量的疲劳寿命下限估计值表达式,采用数值积分的方式得到只含有随机变量的结构疲劳寿命上、下限值表达式,最后根据概率疲劳寿命分析方法可以得到一定置信度下的寿命上、下限值。算例结果表明:本文方法能够解决含概率-模糊-区间混合变量的结构疲劳寿命分析问题,不仅拓展了非概率在疲劳寿命分析中的应用范围,也是对非概率疲劳寿命分析方法的理论补充。
In this paper, a structural fatigue life analysis model with consideration of probability, fuzzy and interval variables is established to solve the structural fatigue life analysis problem under mixed variables. Taking the set of fuzzy variables in the model, the fuzzy variable is degraded to the corresponding interval vector. By making the fuzzy variables reduce to interval variables, the problem is transformed into structural fatigue life analysis with random variables and interval variables. According to the probabilistic and non-probabilistic life analysis method, the random variable under α-level is obtained as the independent variable fatigue life lower limit estimation expression, the upper and lower limit expressions of structural fatigue life with random variables are obtained by means of numerical integration. Finally, according to the probabilistic fatigue life analysis method, the upper and lower limits of life can be obtained under certain confidence. The experimental results show that this method can solve the problem of structural fatigue life analysis with probability-fuzzy-interval mixed variables, and this method not only extends the application of non-probabilities in fatigue life analysis, but also provides the theoretical supplement for the non-probabilistic fatigue life analysis.
出处
《应用力学学报》
CAS
CSCD
北大核心
2018年第4期906-910,共5页
Chinese Journal of Applied Mechanics
基金
国家自然科学基金(51509254)
海军工程大学自然科学基金
关键词
结构疲劳寿命分析
随机变量
模糊变量
区间变量
截集法
fatigue life analysis model of structure
stochastic variable
fuzzy variable
convex variable
cut-set method
作者简介
王磊，男，1992年生，海军工程大学，硕士生；研究方向——舰船动力及热力系统的科学管理。;通讯作者：杨自春，E-mail：wanglei_19921022@163．com
