Studying the effects of non-uniform earthquake excitations on dynamic response of concrete arch dams

In structures with large dimensions such as bridges and dams, owing to the extent of supports, seismic ground motion at interface of different points of the structure and foundation might vary significantly. These real non-uniform motions in usual designs, due to analytical complexities, has been marginalized. While few studies reveal that for exact evaluation of seismic safety of dam, attention to non-uniform excitation is necessary. This paper studies the seismic response of dam-reservoir-foundation systems subjected to non-uniform motions. A high concrete arch dam is selected as the case-study example and its analytical model is subjected to seismic uniform and non-uniform motions. After performing finite element linear dynamic analysis, the results are compared and assessed. According to the results, imposing non-uniform excitation lead to significant differences in displacement responses and stresses.