Seismic Performance Evaluation of Concrete Gravity Dams in Finite-Element Framework

Abstract

This article deals with the seismic performance evaluation of concrete gravity dams considering fluid–structure–soil interaction in a finite-element framework. Two-dimensional finite-element formulation and analysis of dam–reservoir–foundation system was carried out in MATLAB code. A displacement-based Lagrangian technique was adopted for the dam and foundation domain, and the reservoir domain was modeled using the pressure-based Eulerian technique. The fluid–structure–soil interaction problem was solved using a direct coupling methodology. The coupled system consisted of three domains: dam, reservoir, and foundation. Free vibration analysis was performed to observe the effect of the interaction with the reservoir and foundation on the natural vibration modes of the dam. Dynamic response quantities of the dam, such as crest displacement and principal stresses at heel and neck were obtained considering interaction with and without the reservoir and foundation. The alteration in the responses of the reservoir and foundation based on the interaction with other domains was also examined. Emphasis was placed on the variation of the dynamic behavior of the dam, reservoir, and foundation when considered in a coupled manner. Finally, the seismic performance of concrete gravity dams was evaluated following a rational methodology based on the outcome of linear time history analysis. This study considered all the necessary modeling and analysis aspects to represent the actual physical scenario of the dynamic behavior of concrete gravity dams, and it provides a descriptive presentation of a simple and efficient approach for seismic safety assessment.