用时域边界元法分析半圆表面裂纹的动态应力强度因子

The Analysis of Dynamic Stress Intensity Factor for Semi-Circular Surface Crack Using Time-Domain BEM Formulation

发展了时域边界元法在分析三维裂纹的动态应力强度因子 (DSIF)方面的应用 ,采用了等参单元及其奇性元很好地模拟了三维裂纹应力场奇异性 ,首次用时域边界元法位移方程计算了半圆表面裂纹的DSIF· 提出并讨论了时间步长的选取方案· 自编了时域边界元法动态分析程序 。

The time-domain BEM was de veloped to analyze the dynamic stress intensity factor (DSIF) of 3-D elastodynamic crack problems. To simulate the stress singularity along the front of a crack, eight-node isoparametric sing ular elements were used, and the DSIF for a semi-circular surface crack was fir stl y calculated based on displacement equation using the time-domain BEM formulatio n. The new scheme to determine the time step was brought forward. By the dynami c analysis program of time-domain BEM compiled by us, several numerical examples a re presented, which demonstrate the unconditional stability and high accuracy of time-domain BEM applied to 3-D elastodynamic crack problems.