Research On Application Of The Simulated Earthquake Motion Based On Wavelet Packet Method

Ground motion simulation can provide a large amount of ground motion time history data required for structural seismic design for actual engineering projects.Starting from actual seismic records,this paper studies the variation of ground motion coherence with frequency and distance based on four sets of actual seismic data recorded by different arrays and the seismic response of the frame structure.Subsequently,using the ground motion simulation software Sim GM,three sets of different seismic acceleration time history data were simulated for different actual seismic records,and their ground motion coherence functions were calculated,and compared with the actual seismic record data in terms of PGA and acceleration response spectrum.Finally,the actual ground motion data and the simulated ground motion time histories were input into the Open SEES finite element frame model as the seismic action,and the difference of the structure response under the actual and simulated ground motions was compared and analyzed to verify the practical engineering applicability of the simulated ground motion.The main research contents are as follows:The actual three earthquake records of Taiwan's SMART-1 array and the actual Parkfiled seismic data recorded by the US UPSAR array were selected as the seismic data used for time history analysis in Open SEES.The coherence function values between the seismic wave data recorded at the C00 of the central station of the SMART array and the ground motion data recorded by the stations on the inner circle,the middle circle and the outer circle are respectively calculated,as well as the value of the coherence function between the ground motion data recorded by the P01,P02,P05 and other stations in the UPSAR array.And then,the calculated coherence function value is fitted and the variation law of the coherence coefficient curve with distance and frequency is analyzed.The coherence function model selected for fitting is the Loh coherence function model,with the tool named Origin curve plotting software.Analyzing and Comparing the variation and laws of the horizontal ground motion coherence function in different earthquake events,it is found that frequency and distance have a great impact on the ground motion coherence,and the fitting curve of ground motion coherence function shows a gradual decrease trend with the increase of frequency,but the magnitude of the decline is different.The frame model vertex displacement,the inter-story displacement angle and the beam-column Kunnath damage index of the structural response under the actual recorded ground motions of different arrays are calculated.And the main damage positions of the frame structure under the earthquake action and the damage of the beam-column members are analyzed.The ground motion simulation software Sim GM used in this article is introduced.This software is used to simulate several groups of different ground motion acceleration time histories under corresponding earthquake events,and the ground motion coherence between them is calculated.Finally,in order to verify the practical engineering application of the simulation group ground motion,the simulation group ground motion was compared with the actual seismic record time histories from many aspects: such as PGA,acceleration response spectrum,frame structure ground motion response,etc..