基于模糊失效准则的机械结构广义静强度的模糊可靠性计算理论

结构的常规可靠性分析是基于要概率论的。然而，在结构可靠性分析中模糊性是固有的。其主要表现在不仅影响结构可靠性的一些基本变量存在模糊性，而且结构的“安全（安全）”与“失效”之间往往秒存在清晰的界限。为此，在介绍了结构可靠性的基本概念之后，分析了影响结构可靠性的不完善性和模糊性因素，提出了结构模糊可靠性计算的统一模型，定义了模糊安全状态的三种不同形式，建立了以状态变量表示模糊安全状态时的广义静强度模糊

FUZZY RELIABILITY ANALYSIS OF GENERALIZED STATIC STRENGTH OF MECHANICAL STRUCTURE BASED ON FUZZY FAILURE CRITERION

Conventionally, probability theory has been used in structural reliability analysis. However, fuzziness is inherent in structural reliability analysis. The fuzzy performance is based on the consideration that the structural perfor mance can't be necessardy classified into crisp categories and that the transition from safety state to failiure state is not sharp. The fuzziness can be handled by fuzzy sets theory. Thus, in this paper, basic concepts of structural reliability are introduced, the imperfection and fuzziness affecting the structural reliability is analyzed, the concept of fuzzy safety state is developed, and the formulas for the fuzzy reliability of generalized static strength are deduced with the use of different membership functions and different prohability density functions. It is shown that the fuzzy reliability is consistent with the conventional reliability. The utility of the concept and the associated methodology is demonstrated by applications to selected example.