基于损伤累积理论的多轴疲劳寿命预测方法  

An evaluation method of fatigue life under multi-axial loading based on damage accumulation theory

作　　者：张莉[1] 唐立强[2] 付德龙[1] 

机构地区：[1]哈尔滨工业大学航天科学与力学系,哈尔滨150001 [2]哈尔滨工程大学建筑工程学院,哈尔滨150001

出　　处：《哈尔滨工业大学学报》2009年第4期123-125,共3页Journal of Harbin Institute of Technology

基　　金：黑龙江省自然科学基金资助项目(A01-10)

摘　　要：为估算工程构件的疲劳寿命,建立一种基于损伤累积理论的多轴疲劳寿命预测方法.利用有限元法和疲劳损伤累积理论对6种损伤参量进行修正,计算得到在单轴、双轴比例、双轴非比例、三轴比例和三轴非比例循环载荷作用下疲劳损伤累积规律,建立一种幂指数形式的损伤演化方程,估算疲劳寿命,并与试验结果进行比较.计算结果表明:单轴疲劳载荷作用时,损伤累积规律是线性的;多轴疲劳载荷作用时,损伤累积规律是非线性的;由这种方法预测的双轴比例、非比例加载的疲劳寿命与试验值吻合得很好.得到一种可解决三轴非比例加载疲劳问题的寿命预测方法,这种方法所需由试验确定的常数少.To evaluate the fatigue life of engineering components under multi - axial loading, a method based on damage accumulation theory is presented. Six damage parameters were modified using the finite element method and the damage accumulation theory. The fatigue damage accumulation rules were calculated under uniaxial, biaxial proportional, biaxial non-proportional, triaxial proportional and triaxial non -proportional loadings. The exponential equation of damage evolution was established to estimate the fatigue lives under different loadings, and the calculation results were compared with experimental results. It is shown that the damage accumulation rules are linear under uniaxial loading, while they are non-linear under multi-axial loading. The calculation results agree well with experimental results. The derived life evaluation method can be used to solve the problems of fatigue under triaxial non-proportional loading and needs less constants to be determined in experiment.

关 键 词：多轴非比例加载 损伤累积 寿命估算方法 

分 类 号：O36[理学—流体力学]