Investigating the Performance of Nonlinear Dynamic Analysis mechanisms of the Dam-Reservoir-Foundation System based on the Seismic Damage Level

The purpose of the present research is to investigate the damage analysis mechanisms of the Dam-Reservoir-Foundation system using the Finite Element Method (FEM). The study focuses on the Koyna dam-reservoir-foundation system, which is a two-dimensional model that has been subjected to the horizontal and vertical components of ground acceleration in the Koyna earthquake using ABAQUS software and the Concrete Damage Plasticity (CDP) model. The comparison of models in linear and linear analysis shows that considering the bottom of the foundation for applying the load increases the seismic damage compared to applying the bottom of the dam. The results indicate that applying foundation excitation at the contact surface of the dam-foundation in the condition of foundation without mass, as well as applying foundation excitation at the level of the rock foundation in the condition of massed foundation can lead to a more accurate prediction of the response of the structure during an earthquake. However, the level of seismic damage in the dam is greatly affected by how the base excitation is applied and the mechanism of the modeling Dam-Reservoir-Foundation system. Therefore, it is crucial to consider the correct application of base excitation and the modeling mechanism while analyzing the damage analysis of the Dam-Reservoir-Foundation system.