The effects of ice cover on stochastic response of concrete gravity dams to multi-support seismic excitation

Abstract

In this study, the ice cover effects on stochastic seismic response of concrete gravity dams subjected to multi-support seismic excitation are investigated including ice-dam-reservoir-foundation interaction. Ice-dam-reservoir-foundation interaction system is modeled by finite element method using ANSYS program. The ice-dam-reservoir interaction system is modeled using the Lagrangian (displacement-based) fluid and solid-quadrilateral-isoparametric finite elements. The ground motion is described by filtered white noise and applied to each support point of the two-dimensional finite element model of the dam reservoir-foundation system. The east-west component of Erzincan earthquake, which occurred on 13 March 1992, is taken into account for the stochastic dynamic analysis of Sanyar concrete gravity dam. Solutions are obtained for dam-reservoir-foundation and ice-dam-reservoir-foundation systems, separately. Parametric studies are conducted in order to investigate effects of the variation of the length, thickness, elasticity modulus and its density of the ice cover on the seismic dynamic response of the dam. It is observed that the variations of the values of the length, thickness. and elasticity modulus (except density) of the ice cover influences the stresses of the coupled system considerably. (C) 2008 Elsevier B.V. All rights reserved.