广义T应力对裂纹应力强度因子的影响

裂纹尖端的奇异应力场可以表达为Williams级数展开的形式,其中常数项(即T应力项)和非奇异项对裂纹尖端的应力应变场有着很大的影响,这些影响反过来作用于裂纹应力强度因子的计算.将T应力项和非奇异项合称为广义T应力,提出一种用特征分析法和边界元法配合求解广义T应力的新思路,可以根据需要任意选取广义T应力的项数,进而研究广义T应力对应力强度因子计算的影响.结果表明,考虑广义T应力项的应力强度因子计算结果与实验结果更加接近.

Effect of general T-stress on stress intensity factor of a crack

The singular stress field at a crack tip can be presented by the Williams series, where the constant term is named T-stress. The constant term and non-singular terms, which are called general T-stress here, play a significant role in determining the stress and strain fields around a crack tip which in turn can affect the calculation of stress intensity factor (SIF) of the crack. Herein, a new method which combines the singularity eigen-analysis with the boundary element method was proposed to determine the general T-stress in the crack tip. Then the effect of the general T-stress on the calculation of the stress intensity factor of a crack was studied. The numerical results show that the stress intensity factors taking account into the general T-stress are more proximate to the experiment results.