结构疲劳裂纹扩展寿命的区间预测  

Interval Prediction of Structure Fatigue Crack Propagation Life

作　　者：魏宗平[1] 

机构地区：[1]宝鸡文理学院机电工程系,陕西宝鸡721016

出　　处：《机床与液压》2013年第15期61-64,共4页Machine Tool & Hydraulics

基　　金：陕西省教育厅科研计划资助项目(09JK333);宝鸡文理学院重点科研计划项目(ZK10142)

摘　　要：针对结构疲劳裂纹扩展寿命预测中参数不确定性会导致结构裂纹扩展寿命偏差较大的问题,在分析过程中考虑结构材料特性、载荷和裂纹尺寸等的不确定性,将影响结构疲劳裂纹扩展寿命的不确定性参数视为区间变量,给出了疲劳裂纹开始扩展的区间条件;以Paris公式恒幅载荷疲劳裂纹扩展寿命计算公式为基础,提出了恒幅载荷和变幅载荷作用下结构疲劳裂纹扩展寿命预测的区间模型,并且给出了该区间模型求解的优化方法。通过工程实例计算,表明该方法是可行、有效和简便的,它可以作为结构疲劳裂纹扩展寿命预测的一种新方法。The uncertain parameters of structure fatigue crack propagation life prediction can lead to deflection of structure crack propagation life.The effect of some uncertain parameters such as material and geometry and loading on structure crack propagation life was considered.The uncertain parameters were described as interval numbers.The conditions that the crack began to propagate was given.Interval prediction model of structure fatigue crack propagation life for the constant-amplitude and variable amplitude loading was obtained based on the Paris formulas of amplitude fatigue crack propagation life and an optimal method was presented for solving the interval prediction model.Engineering examples are used to illustrate that the proposed method is feasible and reasonable and practicable for structure fatigue crack propagation life prediction.It can be used as a new method of structure fatigue crack propagation life prediction.

关 键 词：疲劳 裂纹扩展寿命 不确定性参数 区间预测 

分 类 号：TB114.3[理学—概率论与数理统计] O213.2[理学—数学]