The Study On Complex Foundation-structure Static And Dynamic Interaction

Baise hydroelectric station lies on You river, which is a branch of Zhujiang river. It is a big all-around benefits hydro-junction. The role of intake tower is very important in the hydro-junction. The stability of intake tower and access ramp plays a key role in the failure-free operation of the hydro-junction. Considered the complexity of geological structure, how to study the interaction of intake tower and slope is important both in theoretical research and engineering.The stability of rock slope is affected both by the interior action of rock mass and by the exterior factors of environment. Its stability is the result of the multi-factors. So, it is difficult to analyze the stability of rock slope. At present, limit equilibrium method is one of the conventional slope stability analysis methods. The calculation results by the method don't always conform to the facts, since the rigid body assumption and the assumed direction of inactive forces between slices in this method. Furthermore, it is difficult to analyze 3D slope with limit equilibrium method, considered the complexity of geologic structure. The other analysis methods of rock slope have respective advantages, but when many forces are considered (for example, gravitation, seepage force and earthquake force), these methods are as not convenient and effective as finite element method. 3D nonlinear finite element method is applied to analyze the stability of rock slope in the paper. When using this method, the thin layer element is used to simulate interlayer and structural joint for sliding surfaces. The static and dynamic analysis of intake slope of Baise hydroelectric station is calculated by this method. The stability of the intake slope during construction and operation are obtained in the paper.The analytical methods about foundation-structure interaction have two main categories. They are analytic methods and numerical methods. At present, finite element method, sub-structural analysis method and mixture method are common methods. When both foundation and structure are considered in analysis, interface problem on interface of them is keystone. Several common interface elements are described in the paper. When the foundation and the intake tower are both important analytical objects, and the geological condition of foundation is very complex, the slope is meshed with tetrahedral element, while the intake tower is meshed with hexahedral element. For this problem, compatible displacement method of different mesh is presented in the paper. On the interface of different mesh, nodes belonging tostructure or foundation are regarded as basic nodes, and nodes belonging to the other side are regarded as subordinate nodes. The linear interpolation relation between basic nodes and subordinate nodes is founded on the interface. So global linear equations are deducted. In these equations, unknown variables are basic nodes. Based on these assumptions, compatible displacement relation is founded on the interface of foundation and intake tower.The common methods of foundation-structure dynamic interaction are summarized and their advantages and shortages are analyzed in the paper. For Baise hydroelectric station, response spectrum of mode-superposition is applied in the dynamic analysis of intake tower. The rational conclusions are obtained.3D nonlinear finite element method, compatible displacement method of different mesh and response spectrum of mode-superposition are used to analyze the intake tower-intake slope static and dynamic interaction, since the complexity of geologic structure. The rational results provide a feasible way for the similar projects analysis in the future.