双向载荷作用下无限大板中源于正方形孔的分支裂纹的应力强度因子

为研究源于正方形孔的一对分支裂纹问题提出一种边界元法,该边界元方法由Crouch与Starfield提出的常位移不连续单元和裂尖位移不连续单元构成.在该边界元方法的实施过程中,左、右裂尖位移不连续单元分别置于裂纹的左、右裂尖处,而常位移不连续单元则分布于除了裂尖位移不连续单元占据的位置之外的整个裂纹面及其他边界.算例说明,这种边界元法对计算平面弹性复杂裂纹的应力强度因子非常有效.给出的双向载荷作用下无限大板中源于正方形孔的一对分支裂纹的应力强度因子的详细数值结果,可以揭示双向载荷参数对应力强度因子的影响.

Stress intensity factors of branching cracks emanating from a square hole in an infinite plate under biaxial loads

This study concerns with a pair of branching cracks emanating from a square hole by means of a boundary element method which consists of the constant displacement discontinuity element presented by Crouch and Starfield and the crack tip displacement discontinuity elements proposed by the author.In the boundary element implementation the left or the right crack tip displacement discontinuity element is placed locally at the corresponding left or right crack tip on top of the constant displacement discontinuity elements that cover the entire crack surface and the other boundaries.Numerical examples are included to show that the present numerical approach is very efficient and accurate for calculating stress intensity factors of plane elasticity crack problems.Specifically,the numerical results of stress intensity factors of a pair of branching cracks emanating from a square hole in an infinite plate under biaxial loads are given,which can reveal the effect of the biaxial load parameter on stress intensity factors.