Seismic Response Analysis Of High-Rise Building Under Different Types Of Multi-Dimensional Earthquake Ground Motions

High-rise building has become the major structure type for business and residential use in most cities of our country,thus the seismic safety is of many significance in preventing life and property loss for our society.Based on systematically review of the development of high-rise building structure,structural analysis methods and multidimensional earthquake ground motions,Seismic response analysis of high-rise building under different types of multidimensional earthquake ground motions are conducted,the main content of this work are:(1)Based on the rules of selecting different types of earthquake ground motions,three different types of earthquake ground motions such as normal far-field ground motions,pulse-like near-fault ground motions and non-pulse near-fault ground motions are selected from world seismic data base,then,the velocities,Fourier spectra and response spectra are calculated.The analysis shows that pulse-like near-fault motions have obvious velocity pulse;vertical component of near fault motions has more high-frequency content than far-field motions;the normalized response spectra of vertical component is smaller than the other two horizontal components in high-frequency part for far-field motion,so the disadvantage of vertical component should be considered when the epicentral distance is small.(2)Based on elastic wave theory,the rotational components of different types of earthquake ground motions are calculated and the characteristics are analyzed.The analysis shows that the rotational components also have velocity pulse as the translational motions for the pulse-like near-fault motions;for same earthquake event,the rotational components contain more high frequencies than corresponding translational components;among the three rotational components,rocking motions is bigger than torsional component.(3)The finite element model of high-rise building structure is built and analyzed under different types of multidimensional earthquake ground motions by using time history dynamic method.The results show that the pulse-like near-fault ground motion has more serve effect on structural response,which is bigger than the other two types of ground motions;rotational components have significant influence on structural response of high rise building;the seismic response of high rise building isstrongly related to the types of ground motions and the translational and rotational components input.Therefore,it is necessary to consider the types of earthquake ground motions and include the rotational components in the structural seismic design.