Dynamic Response Analysis Of The High-thin Arch Dam Under Seismic Action

With the vigorous development of water conservation,there are a large number of high arch dams and thin arch dams has been built or are in the preparation.At the same time,The western region is located in the Himalayan seismic belt,is one of the main seismic zone on the planet,it is the most active area of seismic activity on the Chinese mainland,the above magnitude 7 earthquake of history in our country,about 70% have occurred in this region.Therefore,it is the most important to accurately and timely evaluate seismic safety performance of high thin arch dam in the water conservancy project construction management.In this paper,in order to study dynamic response analysis of high and thin arch dam under seismic loading,relying on Chongqing Gaixia high thin arch dam project which height of dam is 160 m and thickness ratio is 0.106 as the research object,The main research contents and results are as follows:1 ? Based on treatment method of dynamic artificial boundary,the theory of dynamic dam-water-interaction and the analysis method of structural natural vibration characteristic,response spectrum method with dynamic dam-water-interaction and time-history analysis method with viscous-spring boundary,it is better to high thin arch dam modal calculation,seismic dynamic response analysis of high thin arch dam and analysis of dynamic response influence factors.2?Based on APDL language of the large-scale finite element software ANSYS,the high and thin arch dam parameter finite element model is automatically established and the analysis of the stable temperature field is made by applying temperature load.Then,based on finite element method,the high and thin arch dam under different working conditions of temperature rise and temperature drop is calculated by hot-structure analysis,it is concluded that under complication loads,the upper body of dam produce a larger displacement and the location which the dam body and foundation contact create a stress concentration.3?The fluid-structure coupling model of dam-water and the finite element model of arch dam-foundation-water are built to analysis structural natural vibration characteristic of high thin arch dam.The researches show,the dam's natural frequency which considers fluid-structure coupling effect is higher than the dam's natural frequency which makes Westergaard-adding mass method by water.Then,accordingto the response spectrum method to calculate the seismic response and superposition with the static results,it is concluded that the high thin arch dam in the most adverse response under the action of the static and dynamic.4 ? Based on the finite element model of Gaixia high thin arch dam,using time-history analysis method,this paper discusses two important factors that affect the dynamic response of high thin arch dam.They are dynamic dam-water-interaction,the radiation damping of foundation.It is concluded that the dam's displacement and stress that considers dynamic dam-water-interaction is greater than does not consider dynamic dam-water-interaction results,therefore,considering the radiation damping of foundation is better to avoid the false amplification of dam seismic response.5?Based on time-history dynamic analysis method to study the dynamic response of high-thin arch dam,When the high thin arch dam meets with frequent and rare earthquake and design response spectrum earthquake.At the same time,the results are compared with response spectrum method.Some measures that are better to enhance the seismic performance are given on the basis of research results.