随机循环载荷, 疲劳寿命, 累积损伤, 载荷作用次数, 寿命预测

Based on the nominal stress method for fatigue life prediction, a predicting model for the fatigue life of mechanical structures under random cyclic loads was developed herein. The uncertainty of the cyclic loads applied on the mechanical structures was analyzed. With the number of load application as the life index, the fatigue life prediction models of mechanical structures under random cyclic loads were developed with the probability weighted method and the Miner linear cumulated damage rule, when the relationships between fatigue life and stress can be expressed as the exponential function and the power function, respectively. Finally, the models proposed were used to predict the fatigue life of a rotating shaft.