杨房沟拱坝整体稳定性的三维非线性有限元分析与地质力学模型试验研究

Global stability of Yangfanggou Arch Dam by 3D nonlinear FEM analysis and geomechanical model tests

保证拱坝的整体稳定是拱坝设计和建设的重要问题。拱坝整体稳定性问题是一个涉及非均匀性、多裂隙介质、不可逆内部损伤演化的三维非线性问题。非线性有限元和地质力学模型试验是研究这类问题的最主要方法。通过三维非线性有限元(TFINE程序)对杨房沟拱坝-地基进行三维数值模拟,并采用200∶1的模型比例尺对杨房沟拱坝-地基进行三维地质力学模型试验。分别根据数值模拟和模型试验的结果对拱坝的位移和应力分布规律,破坏机理和整体稳定性进行分析。两者结果吻合较好。通过综合数值模拟和模型试验的分析结果对拱坝的整体稳定性做出评价,给出坝肩岩体相对薄弱的部位,并对拱坝设计和地基处理提出建议。

The global stability is an important aspect in design and construction of arch dams.The global stability of dams is a three-dimensional nonlinear problem which involves heterogeneity,porous media,irreversible damage evolution.The nonlinear finite element method and geomechanical model tests are the main means to study the global stability of arch dams.Numerical simulation by a nonlinear finite element method(TFINE code) and a geomechanical model test with scale of 200∶1 are introduced.The displacement and stress distribution rules,failure mechanism and global stability of dams are explored according to the simulations and tests respectively.Both results are in good agreement.The global stability of the dams is evaluated synthetically by combining the results,the relatively weak site of abutment rock mass is provided,and some advises are proposed.