The earthquake response of a high concrete gravity dam-reservoir-foundation system has been investigated, in order to study the effect of foundation flexibility and reservoir on the response of a high concrete dam under both harmonic and transient analysis. The dam has been idealized by considering a separate monolith under plane stress conditions, and a foundation block as plane strain. The modelling of the reservoir has been carried out using a fluid acoustic element, and proper consideration of the fluid-structure interaction has been considered. The foundation block has also been replaced by soil springs, and its stiffness and damping values have been calculated using empirical formulas. The added mass approach has been adopted, as per Indian standard code IS1893-1984 and Westergaard’s method, to compare the frequency results of the model with fluid element. The effect of foundation flexibility and reservoir height has also been studied in both frequencies, as well as in time domain.
