疲劳是承受循环载荷的金属结构最重要的失效机制，现已有多种金属疲劳寿命预报方法。实际的设计、制造、加工和操作等工序环节中总是存在不确定性，这些不确定性的影响将在结构的疲劳寿命中富集，为此发展了疲劳可靠性分析。该文讨论了将疲劳可靠性分析方法和统一的疲劳寿命预报方法（UFLP）相结合的可行性，为海洋结构物的安全使用提供参考。文中的极限状态方程是基于统一的疲劳寿命预报方法（UFLP）得到的，并讨论了其中各参数对疲劳寿命的影响；针对一组TC4-ELI的疲劳裂纹扩展数据，分别采用Monte-Carlo法和JC法开展了疲劳可靠性分析，两种分析方法得到的结果彼此符合得较好。%Fatigue is generally the most common failure mechanism of metal structures, and it is widely known that there always exist uncertainties in structures because of variations in the process of de-sign, fabrication, manufacture, and operation. Those uncertainties may be transmitted into the fa-tigue life of structures under cyclic loads, and fatigue reliability analysis methods are developed to ac-commodate those uncertainties in the prediction of fatigue life. In this paper, the feasibility to com-bine the unified fatigue life prediction (UFLP) method and the reliability analysis methods is carried out to offer a safety guidance in the usage of the structures. The limit state function is established based on the UFLP, and the effect of every parameter in fatigue life estimation is evaluated, then the fatigue reliability analysis based on a series of experimental data is carried out as an example by means of both the Monte-Carlo simulation and the JC method, the results of which are in good a-greement with each other.
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