模拟开挖过的非线性自适应多重网格有限元方法

NONLINEAR ADAPTIVE MULTIGRID FEM FOR SIMULATION OF EXCAVATION PROCESS

开发了模拟多步开挖过程的非线性自适应多重网格有限元方法。实现了随开挖工作面不断移动而自适应加密有限元网格的过程 ;提出了变化网格中的已知边界荷载及开挖边界释放荷载的移置方法 ;为适应增量荷载下自适应有限元分析的需要 ,研究了不同网格间有限元计算结果的传递及网格退化处理等问题。最后 。

Nonlinear adaptive multigrid FEM for simulating multi-step excavation process was studied.An adaptie procedure for refining finite element mesh with excavating faces moving continually was realized,the methods of equivalently transforming boundary loads,which were given in advance or were released by excavating in variational mesh,were put forward.To meet the needs of adaptive FEM analysis for structure loaded step by step,the key problems such as the transferring of calculated mechanical results between two meshes,the de-refining of refined mesh in the calculating process were successfully discussed.Validity and advantage of adaptive FEM used for simulating analysis of excavation constructing process were shown by calculated example.