Evaluation of the response of RCC dams to earthquakes with different frequency contents

In this paper, a procedure for evaluating the response of RCC dams to earthquakes with different frequency contents is proposed. The seismic analyses are performed on a finite element model that consists of the RCC dam and rock basement. The stiffness constrast of the dam and the soil foundation is a parameter that plays an important role in the seismic response. The development of the methodology involves the analysis of multiple configurations of dams so an interpolation method and a data base have been implemented in a computational application. The methodology describes the ways to reduce the number of cases to study with an adaptation of the square-cube law first described for Galileo Galilei. Finally, an example is developed for four seismic excitations for which the corresponding accelerograms have the same maximum acceleration but different frequency content. Seismic analyses are performed using the dynamic step by step method. Results from this study indicate that the seismic response is highly dependent of shear modulus ratio as well as the type of rock basement.