The common tool used in the design of gravity dams is still linear analysis. However, nonlinear tools have to be utilized for the evaluation of the seismic safety of older dams designed for lower seismic risk especially in the developed world. In contrast to the experience in linear analyses of the dam monoliths, the non-linear behavior and performance limits of these systems are not well known. This study is focused on investigation of the behavior of a gravity dam monolith using incremental dynamic analysis with the purpose of determining the development of damage on the monolith and the corresponding cracking patterns. The constitutive model for the material was calibrated first to the existing experimental results to verify the ability of the utilized cracking model to simulate the fracture in this material. Incremental dynamic analysis was then conducted using 21 different ground motions in order to assess the damage state on the dam for increasing intensity measures (IM). The relation between the development of cracking on the system and the IMs was investigated. The results show that in lieu of spectral acceleration, velocity based IM are more effective in determining the damage process on the monolith. A simple equation for the prediction of the damage development on the monolith was proposed based on the velocity characteristics of the ground motions chosen.
