Analysis of Dynamic Damage Characteristics of Gravity Dams Based on Viscoelastic Boundary
The dynamic interaction between gravity dams and foundations is a very complex research topic,in which the input of seismic motion has a particularly important impact on the dynamic response of gravity dams.Due to the traditional massless foundation being unable to reflect the inertial effect of foundation mass and the dissipation effect of seismic waves at the cutoff boundary,it is not possible to truly simulate the dynamic response of gravity dams.By setting viscoelastic boundaries at the cutoff boundary of the foundation,the effect of seismic wave dissipation towards the far-field foundation can be well simulated,transforming the closed foundation system using massless foundation into an open foundation system in real situations.This article aims to simulate the dynamic response of the koyna gravity dam more realistically.A dynamic damage model for Koyna gravity dam was established based on the theory of damage mechanics.The transmission process of Koyna seismic waves in the foundation was simulated by setting a viscoelastic boundary at the cutoff boundary of the foundation.The dynamic damage characteristics of Koyna gravity dam under earthquake are analyzed from three aspects:damage distribution,displacement and energy dissipation.The results show that the viscoelastic boundary can truly simulate the radiation damping phenomenon of the far-field foundation,absorb the scattered wave energy transmitted to the boundary,and have good computational stability.The use of viscoelastic boundary and damage mechanics can effectively simulate the damage characteristics of gravity dams under earthquake action.
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万方数据
维普
