提出了一种将残余应力作为初始应力的疲劳裂纹萌生寿命计算方法,将其应用于定量分析残余应力对疲劳累积损伤的影响。基于临界面法,在焊接残余应力和多轴载荷双重作用下进行疲劳损伤参量分析,并与试验结果进行了比较。结果表明,将焊接残余应力作为初始应力进行估算得到的结构疲劳裂纹萌生寿命,比常规的按照残余应力公式修正的结果更接近试验值。
This paper puts forward a kind of calculation method for estimating fatigue crack initiation life by considering welding residual stresses. The method can quantitatively analyze the influence of residual stresses on the cumulative fatigue damage. Based on critical plane approach, analysis of damage parameters is performed under both welding residual stress and multi-axial loads. After a comparison between numerical and experimental results, it is concluded that the result of the present method is closer to the experimental value than that obtained with empirical formula method in the prediction of fatigue crack initiation life of a structure.