摘要
概述了二滩水电站地下厂房洞室群的超大规模的、模拟开挖过程的三维非线性有限元分析,以及分析中的一些全新的处理方法.据此,对地下洞室群三维非线性FEM分析中若干具有共性的问题提出了看法、讨论与建议,包括:在地应力主方向与洞室轴线不平行时,地下洞室群进行三维非线性分析不可替代性;地应力场的获得与校核对得出合理计算结果的重要意义;有限元建模中数值误差与理论简化相适应,以保证计算的合理性与可行性;开挖步骤的模拟对非线性分析中发现破坏位置和破坏时间必要性等.此外,对部分计算结果进行简要的分析.
In this paper, with the help of new methods, we have described the analysis with 3D nonlinear FEM on the grouped cavern of Ertan project. Based on the analysis, we have proposed and discussed some general occurred problems in similar analysis. Some suggestions and conclusions are as follows: Using 3D FEM analysis advantages over 2D calculation, when we take into account the angles between the main direction of geostress and the axial of the cavern. The correct simulation of initial geostress field plays an important part in obtaining reasonable results. Following the excavating of the cavern step by step is necessary especially for the nonlinear analysis, which will be helpful for us to find where and when the cavern would be damaged.
