含模糊-区间变量的结构非概率可靠性优化设计

工程结构中存在着诸多不确定性因素，可靠性方法是处理不确定因素的有效途径之一。针对大量工程结构中存在混合不确定信息的问题，提出了一种适用于工程的混合不确定性可靠度计算方法。将模糊变量转化为区间变量，基于体积比的区间可靠性模型，建立了含模糊-区间混合变量的结构非概率可靠性模型。由于该可靠性模型意义明确，对模糊信息的处理也比较合理，可作为混合可靠性计算方法的一种补充。应用此可靠性模型对某飞机机翼结构进行了优化设计，实例计算说明了该文的方法是有效和可行的。

NON-PROBABILITY RELIABILITY OPTIMIZATION DESIGN FOR STRUCTURES WITH FUZZY AND INTERVAL VARIABLES

The reliability method is one of effective ways to deal with the uncertainty existing in engineering structures.Due to the existence of hybrid uncertainties in many engineering structures,a reliability method of hybrid uncertainties is proposed,and it is suitable for engineering application.Based on the interval reliability model of the volume ratio,a non-probabilistic reliability model for the structure with fuzzy-interval hybrid variables is established by transforming the fuzzy variables into the interval variables.The presented hybrid reliability model can be used as a supplement to the previous methods,as it has a clearer meaning and it is reasonable to deal with the fuzzy information.The proposed model was used in the optimization design of an airfoil,and the numerical example shows that the method is effective and feasible.