Reliability assessment considering dependent competing failure process and shifting-threshold  

考虑相关竞争故障过程及变动阈值的可靠性评估(英文)

作　　者：苏春[1] 瞿众洲[1] 郝会兵[1] 

机构地区：[1]东南大学机械工程学院,南京211189

出　　处：《Journal of Southeast University(English Edition)》2013年第1期52-56,共5页东南大学学报（英文版）

基　　金：The National Natural Science Foundation of China(No.50405021);Graduate Training Innovative Projects Foundation of Jiangsu Province(No.CXLX12_0081)

摘　　要：The reliability assessment problem for products subject to degradation and random shocks is investigated. Two kinds of probabilistic models are constructed, in which the dependent competing failure process is considered. First, based on the assumption of cumulative shock, the probabilistic models for hard failure and soft failure are built respectively. On this basis, the dependent competing failure model involving degradation and shock processes is established. Furthermore, the situation of the shifting-threshold is also considered, in which the hard failure threshold value decreases to a lower level after the arrival of a certain number of shocks. A case study of fatigue crack growth is given to illustrate the proposed models. Numerical results show that shock has a significant effect on the failure process; meanwhile, the effect will be magnified when the value of the hard threshold shifts to a lower level.研究了受退化和随机冲击共同作用的产品可靠性评估问题.考虑相关竞争故障过程,建立了2类概率模型.首先,基于累积冲击假设,分别建立了硬故障概率模型和软故障概率模型.以此为基础,考虑退化和冲击过程建立了相关竞争故障模型.此外,研究了因多次冲击载荷作用而导致的硬故障阈值下降的情形,分析故障阈值的变动对产品可靠性的影响.以一组裂纹增长数据为例,验证模型的有效性.研究结果表明:冲击对产品故障过程有着显著影响,同时硬故障阈值的下降会进一步加剧上述效应.

关 键 词：degradation hard failure dependent competing failure process cumulative shock model shifting-threshold 

分 类 号：TH17[机械工程—机械制造及自动化]