Analysis Of Structural Seismic Response Based On Viscous Dampers Under Near-fault Earthquakes

The near-fault ground motion is affected by the forward direction effect and the sliding impact effect,which makes it have larger velocity and displacement pulses,but also contains larger energy,resulting in a larger seismic response of the structure.This paper analyzes the steel frame structure based on viscous dampers under the action of near-fault pulse-type earthquakes.The main research contents are as follows:(1)The characteristics of near-fault pulse-type ground motions are summarized,and the selection method of near-fault pulse-type ground motions is given.Using the strong motion database,the corresponding near-fault pulse-type ground motion data is selected and obtained by analyzing the frequency spectrum of ground motions.The spectral characteristics of near-fault pulse-type ground motions are analyzed.(2)Based on the viscous damping characteristics,an analysis model of the single-degree-of-freedom system is established.By inputting the selected pulse-shaped ground motions into the single-degree-of-freedom analysis model and performing time-history analysis,the seismic response of the single-degree-of-freedom system is obtained;the impulse is established The displacement and acceleration response spectra of the single-degree-of-freedom damping system under the action of a type earthquake are standardized and averaged to obtain the relationship between the pulse period of the near-fault pulse-type ground motion and the seismic response of the single-degree-of-freedom system.(3)Based on viscous dampers,the seismic response of steel frame structures of different heights is analyzed,and the seismic response of the structure under the action of near-fault ground motions with different pulse periods is obtained.The analysis results show that,compared with short-period structures,The viscous damper has a better damping effect on medium and long-period structural acceleration.When the pulse period of the near-fault ground motion increases,the energy consumption of the viscous damper decreases.