失效相关结构系统可靠性分析及近似求解

从分析相关程度对结构系统可靠度的影响入手,对失效相关结构系统可靠性的近似计算方法进行分析,提出了失效相关结构系统可靠度近似求解的新方法,对传统求解方法进行改进·在给定临界相关系数的基础上,按相关程度大小先后把各失效形式分成强相关、弱相关、中等相关3类·首先采用PNET法的有关原则对强相关失效形式进行聚类简化,提取主失效形式,再把各主失效形式分成弱相关和中等相关两类,分别采用不同的近似原则求解系统可靠度,有效地提高了结构系统可靠度求解的计算效率和计算精度·算例验证了方法的可行性和有效性·

Approximate Method to Reliability Prediction of Failure-Dependence System

Starting with a discussion on how the failure dependence affects the reliability of a mechanical structure system and analyzing some existing approximate methods to compute the reliability of failure-dependent structure systems, a new approximate solution is developed to the same with an intention to improve conventional ones. With the correlation coefficients of dependence given, all possible failure modes can be classified as three dependences in accordance to the magnitude of correlation coefficient, i.e. strong, medium and weak dependences. PNET (Probability Network Evaluation Technique) is introduced in the reclassification and simplification of strong-dependent failure modes so as to find the predominant failure modes from them. Then, the predominant failure modes are further classified as weak dependence and medium dependence. According to such different dependences, different approximate solutions are needed corresponding to the reliabilities of various structure systems. The new method can improve greatly the efficiency and precision of the computation to solve the reliability of structure systems, with an example given to show its availability and effectiveness.