摘要：机械设备在服役期间通常承受随机循环载荷的作用，随机载荷的每一次作用相当于在机械系统中造成了一次损伤，当累积损伤量达到了临界损伤值时，即认为系统失效。若机械设备是由多个零件组成的系统，则在随机载荷的作用下，各零件的失效具有一定的统计相关性，已经证明，串联系统的总寿命要低于组成系统的各个零部件的寿命，而并联系统的总寿命要高于各个零部件的寿命。本文基于概率Miner累积损伤理论，借助零件寿命分布的次序统计量来表示系统的寿命分布，建立了系统概率疲劳寿命预测模型。

　　关键词：随机循环载荷； 概率Miner理论； 次序统计量； 概率寿命

Probabilistic Fatigue Life Prediction Model for System Based on the Probabilistic Miner Rule
Lvxiao¹Xie liyang¹
(1. School of Mechanical Engineering and Automation, Northeastern University, Shenyang 110819, China)

　　Abstract: Generally, the mechanical systemissubjected to the random cyclic loads in service,and its damage will cumulateone time when therandom load cycling once.The system failure will occur when cumulative damagereaches the critical damagevalue. If the machinery is a system composed of a plurality of components, a certain statistical dependenceexists in componentfailures,it is certified that the life of series systemis lower than that of component and the life of parallel system is higher than that of component. With the order statistics of life distributions of components to indicate the life distribution of system,a new probabilistic fatigue life prediction model for the system is presented based on the probabilistic Miner rule.

　　Key words: random cyclic load;probabilistic Miner rule; order statistics; probabilistic fatigue life