疲劳与强度耦合下结构系统可靠性研究

Research of structural system reliability considering fatigue-strength coupling

本文首先建立了考虑疲劳载荷和静载荷同时作用下的结构系统可靠性分析模型.并针对在疲劳与强度耦合下的结构系统可靠性分析中,采用改进的分支限界法搜索主要失效模式存在计算量过于庞大的问题,提出一种基于增量时间法来判别系统主要失效模式.引入承损伤比和承力比两个参数,并以该阶段系统的时间增量最小为准则选取进入主要失效模式的单元,组合顺序失效元即可生成系统主要失效模式.该方法可为快速合理评估结构系统可靠性提供理论参考依据.

In this paper, structural system reliability model is established first considering fatigue-strength coupling. For the problem of large amount of calculation of searching main failure mode by using advanced branch-and-bound method, increme- ntal time method is proposed. The bearing damage ratio and bearing force ratio parameter are put forward, and the units, which can be combined to generate the system main failure mode, are found out with the criteria of minimum increment of time. This method can be a theoretical reference for a quick reasonable assessment of structural system reliability.