SIMPLIFIED SOIL-STRUCTURE INTERACTION MODELS FOR CONCRETE GRAVITY DAMS

In this paper, Soil Structure Interaction (SSI) for concrete gravity dams is studied, investigating its effects numerically on a 2D plane strain model under earthquake excitation. In order to highlight the importance of simulating the unboundedness of soil, different modelling approaches have been considered. Furthermore, in order to evaluate the effect of the change in stiffness and density of soil, a parametric study has been performed for each previously defined modelling approach. Finally, dam response is simulated by introducing springs and dampers at the dam base and a 2D simplified model capable of taking into account the SSI has been proposed. The main contribution of this paper is to highlight the importance of modelling SSI in the seismic assessment of gravity dams and the importance of considering soil as half-unbounded domain. In addition, the main parameters playing a role in the SSI for a simplified model have been identified.