基于损伤力学的概率疲劳曲线获取方法

文章基于损伤力学方法获得满足疲劳试验的损伤演化方程,推导出一般条件下的理论疲劳曲线以及相对应的理论中值疲劳曲线与理论理想疲劳曲线；然后根据试验数据即可确定理论疲劳曲线中的参量,从而获取疲劳曲线计算公式。通过此计算公式,可以方便地得到一组以初始损伤为参数的疲劳曲线族,继而得到以失效概率为参数的疲劳曲线族,大大降低了所需试验的数量,并为结构抗疲劳设计和寿命估算提供了依据。

METHOD FOR OBTAINING PROBABILISTIC FATIGUE CURVE BASED ON DAMAGE MECHANICS

Based on damage evolution equation obtained by damage mechanics method and fatigue test data,the theoretical fatigue curve is obtained with the corresponding theoretical median fatigue curve and theoretical ideal fatigue curve under the common condition.Parameters in the theoretical fatigue curve are determined by a few of test data and a formula of fatigue curve is acquired.Using this formula,a group of fatigue curves,taking initial damage as parameter,is received easily.And then a group of fatigue curves taking failure probability as parameter is gained so that the number of test is greatly reduced.This group may provide the foundation for anti-fatigue design and fatigue life estimating.