压载条件下裂纹断裂扩展的位移不连续数值分析

Numerical Analysis on Crack Propagation under Compressing Load by Displacement Discontinuity Method

以土木工程中普遍存在的压缩荷载作用下裂纹扩展演化问题为研究背景 ,通过建立闭合裂纹表面接触阻力的缓和迭代及复合型裂纹尖端应力强度因子 K 、K 的数值渐近解法 ,将位移不连续数值方法 (DDM)应用于压载条件下二维复合型裂纹的断裂扩展分析 ,取得了与理论和实验吻合的计算结果 .所用方法能有效地避免裂纹尖端采用奇异单元及开裂过程单元重划分的繁琐 ,解决了裂纹闭合状态下缝面阻力的合理模拟 ,对压载复合裂纹问题分析有一定参考意义 .

In order to research the problem of compressed crack propagation exiting in civil engineering, a displacement discontinuity method (DDM) was used to solve the crack propagation problem of two-dimensional complex joints under compressing load by establishing the iteration method based on contact resistance mitigation and numerical calculating method of stress intensity factor KI, KII of complex joints. It is shown that the numerical results well agree with the experimental results. The paper provided a way for simulating the contact resistance of crack. It can avoid the complexity of using odd mesh and re-making mesh as the procedure of crack propagation, and give some reference for solving dynamical propagation of compressed complex crack in civil engineering.