SOIL-STRUCTURE INTERACTION MODELING FOR THE DYNAMIC ANALYSIS OF CONCRETE GRAVITY DAMS

During earthquake shaking, the dam-reservoir-foundation system has to be considered a cou-pled system. In this paper Soil-Structure Interaction (SSI) effect is investigated on a 2D plane model of a concrete gravity dam under earthquake excitation. Firstly, different approaches to simulate the unboundedness of soil domain are explored: the Perfectly Matched Layer (PML) technique, the Low Reflecting Boundary (LRB) condition and the Infinite Elements (IEs). Dif-ferent options are compared in the time domain in the case of linear elastic material. The im-portance of taking into account the SSI in the seismic assessment of concrete dams is also highlighted by the energy balance during time. Successively, the effects of SSI are analysed on a full interacting nonlinear plane model. The results which are obtained in terms of material damage and dissipated energy through a parametric SSI simulation in the time domain show the importance of the choice of the damage constitutive law of the material