Performance of concrete gravity dams under earthquake effects

Thesis Type: Postgraduate

Institution Of The Thesis: Orta Doğu Teknik Üniversitesi, Faculty of Engineering, Department of Civil Engineering, Turkey

Approval Date: 2014


Supervisor: YALIN ARICI


Concerns about the seismic safety of gravity dams have increased with the construction of numerous new dams in the developing world as well as the need for the evaluation of existing dam stock in the developed countries. The common procedure for the design of concrete gravity dams has been linear analyses: there is scant experience on the design of such systems using nonlinear analyses as the post-linear behavior and performance limits of gravity dam monoliths are not well known. This study is focused on the investigation of the behavior of a concrete gravity dam monolith using the incremental dynamic analysis (IDA) procedure with the goal of determining the development of damage on the monolith and the corresponding cracking patterns. The constitutive model used was first calibrated to experimental data in order to verify the ability of the model to simulate the fracture in this material. IDA was then conducted using 21 different ground motions in order to assess the state of damage on the monolith for increasing intensity measures (IM). The results show that in lieu of spectral acceleration, velocity based IMs are more effective in determining the damage process on the monolith. A simple equation for the prediction of the damage development was proposed based on the velocity characteristics of the ground motion. Finally, the results of the IDA were compared to the static pushover analysis results in order to evaluate the scope of possible use of such analyses for determining the performance levels of dams.