Seismic Response Of Reservoir Water-dam-foundation System Combined With The Calculation Of FEM-SBFEM

The interaction problem of reservoir-dam-foundation system is one of the most important factors of the dam dynamic response under the seismic loading.The research of the dam dynamic response under the seismic loading is the basis of the safety evaluation of the dams. Based on the Scaled Boundary Finite Element Method(SBFEM) the hydrodynamic pressures of the upstream dam surface are calculated and based on the Infinite Element Method(IEM) the influence of the radiation damping of infinite foundation is considered,then the different conditons of seismic response of reservoir-concrete dam-infinite foundation system applied to two methods is computed.The major content of this dissertation is organized as follows:The hydrodynamic pressures of the upstream concrete dam surface is calculated based on the SBFEM, and it is combined with the FEM calculateing the seismic response of the reservoir-dam-foundation system.Finite element software Abaqus combined with SBFEM, is applied to obtain the seismic responses of reservoir-concrete dam-infinite foundation system based on massless foundation model and infinite foundation model and calculated respectively in the conditions of the different elastic modulus and non-homogeneous foundation, then the results are compared and some meaningful conclusions are obtained. The SBFEM combined with Abaqus evaluate and discuss the seismic dynamic responses and the damage areas of the reservoir –dam-infinite foundation system in the conditions of different elastic modulus, different dampings and the non- homogeneous foundation. The reseach findings have certain reference value for the dam construction and the anti-seismic safety evaluation.The comparing results are calculted as follows:In the elastic cases,with the increase of elastic modulus of foundation, the dynamic response of dam increases gradually.This shows that the dam is impacted largely with the increase of foundation stiffness. In the plastic cases,the elastic modulus of foundation is bigger than the elastic modulus of dam(massless foundation and infinite foundation), the dam heel is damaged and the weak area of the dam is also damaged and runs through the dam surface.But the dam heel has no damaged area when the elastic modulus of foundation is smaller than the elastic modulus of dam,and the weak area of the dam is also damaged and runs through the dam surface.In the elastic cases,the displacement and stress distribution of dam calculated by the massless foundation model are basically identical, except the peak value that incerases apparently, compared with that of the infinite foundation model.In the plastic cases, the damaged areas of non-homogeneous foundation is smaller than the damaged areas of homogeneous foundation,and the initial damage time of non-homogeneous foundation is earlier than the initial damage time of homogeneous foundation.In particular, the time of damage zone of the massless foundation model(non- homogeneous foundation) appears much earlier.