结构体系的非概率可靠性分析方法

结构体系的可靠性与结构的失效模式有关。在非概率条件下 ,结构体系的可靠性取决于非概率可靠性指标最小的最危险失效模式。最危险失效模式的识别及相应极限状态方程的建立是结构体系非概率可靠性计算的关键问题。文中考虑了结构参数及强度、外载荷等参量的不确定性 ,基于随机可靠性方法中常用的优化准则法 ,提出了非概率结构体系主要失效模式的枚举准则。可在只需枚举出少量主要失效模式的情况下 ,不漏掉最危险失效模式。并提出用区间增量载荷法生成主要失效模式的极限状态方程。算例分析表明文中方法是实用和有效的。

A procedure of the analysis of non-probabilistic reliability of structural systems

In the non-probabilistic framework, reliability of structural systems is depended upon the worst failure mode, which has the least reliability indexing all possible failure modes of the structures. Therefore, the identification of the worst failure mode and the establishment of corresponding limit state equations are the critical problems of reliability analysis of the nonprobabilistic structural systems. Considering the uncertainties in structural parameters, strength and applied loads, an optimal criterion enumerating the main failure modes of nonprobabilistic structural systems are presented, which is based on the optimal criterion method used in the probabilistic reliability theory. The method able to ensure the worst failure mode included in a few enumerated main failure modes. The limit state equations of main failure modes are formulated by the increment interval load method. Two numerical examples illustrate usefulness and effectiveness of the proposed procedure.