Performance-based Seismic Design Of Intake Tower

As a kind of important hydraulic structure.When intake tower collapse during earthquake,it will directly influence the hydropower station which power generation and the reservoir water suppply function can’t working properly.In order to prevent the serious secondary disasters,sometimes need to reduce water stage or drain off the reservoir.The structure seismic safety of intake tower is in relation to the security and benefit of the entire hydropower station,so seismic analysis is very important and necessary.Based on the performance-based seismic design in this paper,combining with the project examples,pushover analysis for an intake tower meshed by frame element and layered shell element respectively are conducted.Then the capacity curve of shearing force of the basement of intake tower and the displacement of the roof of structure is obtained from the pushover analysis,which compare the results with those of nonlinear time-history analysis,it can be found that the results of these methods agree well.Finally,come up with the structure of intake tower evaluation under different seismic level.The main works of this paper are as follows:(1) Compare with the intake tower meshed by frame element and layered shell element,the two pushover curve are able to correlate.And the pushover curve of layered shell element are more authentic simulation the elastic and plastic properties of intake tower structure.(2) Compare several defferent lateral load pattern,find out that the results of the downward-pointing triangle model most close to the mode distribution model, three typical earthquake records are selected,comparison between nonlinear time history analysis,the resluts of downward-pointing triangle model are also agree well.(3) Introduced the performance-based seismic design,including seismic resistance level and seismic performance level.Reference to the seismic damages of aqueduct, this paper gives the ultimate state of intake tower,and build the destroy state measurement standard represented by ductility factor.The target displacement of the example under different magnitude earthquake is calculated, and then according the measurement standard designed before,which can analysis intake tower seismic performance under different magnitude earthquake.