ANALYSIS OF SEISMIC RESPONSE OF HIGH ARCH DAMON THE BASIS OF ENERGY BALANCE

摘要

The subject of this paper is seismic analysis of arch dam including nonlinear behavior of contraction jointsunder the strong earthquake excitations. The energy balance for the dam-reservoir-foundation system, infunction of time, is considered. The effects of different energy dissipater installed in the contraction jointon the seismic response of arch dam are investigated.The behavior of energy dissipater under cyclic loads are modeled by nonlinear springs and dashpots. It isshown that the devices increase the capacity of the structure to dissipate energy and may significantlyreduce the seismic response of the structure, but not the change its natural periods particularly. The aim ofthe investigation is to determinate the possibility of establishing a balance of introduced and dissipatedenergy before the construction is turned into a mechanism, as one of the criteria for the assessment of damsafety.In order to increase the energy capacity of the estimation model, in stead of the friction dampers, therubber dumpers with appropriate characteristics are included. The results of the estimations showed thatwith implementation of the energy absorbers in joints, the energy balance can be establishedIn the paper, vertical joints, which would be the most suitable for energy dissipation, programmedbehavior of the dam and passive control of seismic response, were investigated. The parametric analysis ofseismic response of the dam dependency on the characteristic of joints with regard to different levels ofviscous damping and friction and rubber damper was done. Through parametric analysis the values ofviscous and hysteretic damping of chosen joints were determined which are necessary for the establishingof energy balance. On the basis of the values obtained, it is possible to construct joints with suitablecharacteristics with respect to energy absorption.