Dynamic Analysis of Dams Subjected to Varying Earthquake Motions

Many concrete gravity dams have been constructed throughout the world at hydropower, navigation and flood control projects. Some of these structures arelocated where the maximum credible earthquake motion is now considered to be quite strong. This is disconcerting as most concrete dams were designed for earthquakeloading with a pseudostatic analysis using a regional seismic coefficient [28]. In this paper, stochastic dynamic responses of dam–reservoir–foundation systemssubjected to spatially varying earthquake ground motions are investigated using thedisplacement-based fluid finite elements. The spatially varying earthquake ground motion model includes incoherence, wave-passage and site-response effects. Theeffect of the wave passage is investigated by using various wave velocities. Homogeneous medium and firm soil types are selected for considering the siteresponseeffect where the foundation supports are constructed. The ground motion is described by filtered white noise and applied to each support point of the 2D finiteelement model of the dam–reservoir–foundation system. Displacements, stresses andhydrodynamic pressures occurring on the upstream face of the dam are calculated for four cases. It is concluded that spatially varying earthquake ground motions haveimportant effects on the stochastic dynamic response of dam–reservoir–foundation systems

کلیدواژه ها:

Spatially varying earthquake ground motion ، Stochastic analysis ، Lagrangian approach ، Dam–reservoir–foundation interaction ، Fluid finite element