Coupled gravity dam-foundation analysis using a simplified direct method of soil-structure interaction

摘要

A time domain transient analysis of a concrete gravity dam and its foundation has been carried out in a coupled manner using finite element technique and the effect of Soil-Structure Interaction (SSI) has been incorporated using a simplified direct method. A two dimensional plane strain dam-foundation model has been used for the time history analysis to compute the stresses and displacements against earthquake loading considering the effect of soil-structure interaction. An effective boundary condition has been implemented by attaching dashpots to the vertical boundaries. The material damping effects have also been considered and the dam and foundation have both been modeled as linear, elastic materials. To achieve a greater degree of accuracy, the displacements and stresses calculated in the free-field analysis have also been added to those developed in the complete dam-foundation analysis. The proposed algorithm has been simulated for the case of two published problems and in both the cases the results have been found to be in close agreement. The proposed technique is quite simple and easy to implement in the computer code. The outcomes of the results show the efficacy of the developed method.