基于概率断裂力学方法的钢吊车梁剩余疲劳寿命评估

Assessment on the residual fatigue life of steel crane beam based on probabilistic fracture mechanics method

将线弹性断裂力学理论引入到构件剩余疲劳寿命评估中,并推导出变幅应力下构件剩余疲劳寿命公式,由于评估公式中的参数具有很大的不确定性,将其看做服从一定概率分布的统计量,形成基于概率断裂力学的剩余疲劳寿命评估公式。最后,通过实例验证:采用概率断裂力学方法能够对钢吊车梁剩余疲劳寿命做出合理的预测。

By applying the linear elastic fracture mechanics theory to the assessment of residual fatigue life of components,the formula of residual fatigue life under variable amplitude stress was derived.As the parameter in the assessment formula is very uncertain,it is regarded as the statistic that obeys a certain probability distribution,and the assessment formula of the residual fatigue life based on probability fracture mechanics was formed.The example shows that the probabilistic fracture mechanics method can reasonably predict the residual fatigue life of steel crane beams.