修正剑桥模型的隐式积分算法在ABAQUS中的数值实施

Numerical implementation of implicit integration algorithm for modified Cam-clay model in ABAQUS

利用大型有限元软件ABAQUS所提供的用户材料子程序UMAT接口,针对修正的剑桥本构模型开发了隐式积分算法,并且与自动选择时间步长的增量有限元方程迭代解法相结合,对正常固结土与超固结土的三轴排水与不排水试验进行了数值模拟。结果表明,所发展的隐式本构积分算法与时间步长自动选择方法具有较好的稳定性和较高的计算精度,能够得到比较合理的数值分析结果。

The subroutine UMAT special for user-defined material model in the commercial FEM software ABAQUS is utilized and the implicit integration algorithm for the modified Cam-clay model is numerically implemented in ABAQUS. Combined with automatic time increment method for solving incremental finite element equation, the triaxial drained and undrained shear tests of normally consolidated soil and heavily overconsolidated soil are simulated using ABAQUS with the proposed implicit integration algorithm. The robustness and accuracy of the numerical analyses are illustrated. It is shown that the computational results are valid and can well agree with other solutions available.