中文摘要：

工程中多数裂纹构件的受载是随机的,为了更合理、更准确地预测出服役裂纹构件的剩余寿命,针对裂纹构件承受平稳随机载荷且载荷历程的具体特征、载荷水平及载荷作用频度未知的情况,提出了一种预测疲劳裂纹扩展寿命的新方法。该方法根据一段时间对裂纹扩展情况的跟踪观测,推断裂纹扩展规律,实现疲劳裂纹扩展剩余寿命预测。根据应力大小与载荷作用频度是否均已知,将该方法分为两阶段观测法与单阶段观测法。结合一个具体的工程案例,详细阐述了该方法的应用,且验证了其可行性。所提出的方法应用方便、操作简单,可作为工程中预测疲劳裂纹剩余寿命的一种依据。

英文摘要：

Most of the work load of crack components are random,in order to predict more reasonable and more accurate remaining life of crack components,a new method for predicting fatigue crack propagation life is proposed based on the situation that crack components are subjected to steady random load and without knowing the load history,the load level and the load frequency.This method can predict the crack growth law and evaluate the residual fatigue life of crack components by tracking and observing crack propagation.In addition,according to whether the load frequency or the load level is known,the method can be divided into two-stage observation method and one-stage observation method.Besides,this method is expressed and verified in details by a illustrative project example.And this method is proved to be much more convenient and easy to predict the remaining useful life of a crack component in engineering.