对接接头疲劳强度的概率断裂力学研究

A Study on Fatigue Strength of Butt Welded Joints with Probabilistic Fracture Mechanics

利用边界元方法,对对接焊接接头进行了详细的参数应力分析,给出了“未开裂面”应力分布表达式;导出对接接头应力强度因子的权函数,应用Monte-Carlo方法模拟材料性能、几何尺寸等方面的分散性,给出了对接接头疲劳强度的概率断裂力学研究方法.数值模拟与疲劳试验结果基本一致.

The stress of butt welded joints and the corresponding analytical expression for the stress distribution in the prpspective crack plane of an uncracked body are obtained by using the boundary element method. The stress intensity factors for the butt joints are calculated with weight functions developed in this paper. The good agreements of the numerical simulation with the fatigue experiment results show that the Monte-Carlo method is effective to simulate the statistical character of material properies, the joint dimensions and the local shapes of the weld toe.