三点弯曲-剪切试样的应力强度因子

Stress intensity factors of three point bending and shear specimen

利用一种边界元法研究具有偏移边裂纹的三点弯曲-剪切试样.该边界元方法由Crouch与Starfield提出的常位移不连续单元和笔者最近提出的裂尖位移不连续单元构成.在该边界元方法实施过程中,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不论对无限大还是对有限大平面弹性复杂裂纹问题的应力强度因子的计算都是非常有效的.对具有偏移边裂纹的三点弯曲-剪切试样的应力强度因子进行了详细的研究,给出了数值结果.

This paper is concerned with stress intensity factors of a three-point bending and shear specimen with an offset edge crack 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. Test examples are included to show that the method is very efficient and accurate for stress intensity factor calculation of plane elasticity crack problems in both infinite and finite domains. Specifically, the stress intensity factors for threepoint bending and shear specimen with an offset edge crack are studied in detail. Many results are given.