双材料界面裂纹应力强度因子的边界元分析

Boundary Element Analysis of Stress Intensity Factors of Bimaterial Interface Crack

采用双材料基本解建立边界元法基本方程，计算双材料界面裂纹尖端附近的应力和位移场。不离散界面，并设置面力奇异四分之一点裂尖单元以提高计算精度。利用数值外插法得到应力强度因子以避开裂尖场的振荡奇异性。数值结果表明，本文的方法具有较高的精度和效率。

The stress intensity factors of bimaterial interface crack are analyzed using the boundary element method with bimaterial fundamental solutions. The complex stress intensity factors are gained by the modified method which using the traction singular quarter point elements as crack tip elements and using the numerical extrapolation method of determining the stress intensity factors to avoid the oscillation singularity of asymptotic fields of elastic interface crack. In the analysis the interface needs not to be discretized, which is advantageous to improve the accuracy and efficiency of computation.