Analysis And Study On Damping Performance Of Super High Rise Viscous Damping Structures Under Different Types Of Ground Motions

The architectural form and layout of the super high-rise structure are relatively complex,and the time taken for the building to complete a self-vibration is relatively long.Therefore,under the action of long-period ground motion,it will cause the resonance-like phenomenon of the structure,which makes the structure more serious.damage.Earthquake damage of super high-rise structures in Chiji,Taiwan,China and other major earthquakes shows that under the action of long-period component-rich ground motions,some main structures of super high-rise buildings may be functionally damaged,so that they can no longer bear the load.It can't be used again after the earthquake-resistant reinforcement.In this paper,the seismic performance of super high-rise structures under different types of ground motions is studied.At the same time,viscous dampers are arranged on the super high-rise structures according to the needs of energy dissipation and shock absorption to reduce the serious disasters caused by earthquakes.This paper takes a super high-rise concrete-filled steel tube frame-core tube structure as the research object,and comparatively analyzes its basic structure and damping structure under the action of three types of typical long-period ground motions,such as far-field harmonic,near-fault slip and near-fault directivity.The seismic response and energy dissipation of the earthquake are compared,and the near-fault non-pulse type ground motion is compared with the ordinary ground motion.The main research contents are as follows:(1)Analyze the basic characteristics of far-field harmonic vibration,near-fault slip-type ground motion,near-fault directional ground motion,near-fault non-pulse ground motion,and ordinary ground motion.It is concluded that the peak acceleration and peak velocity of near-fault slip type,directivity and non-pulse type ground motion are significantly greater than the far-field harmonic and ordinary ground motions;the record duration and The duration of strong earthquakes is obviously greater than that of the other four types of ground motions;the three types of typical long-period ground motions are rich in low-frequency components,and the excellent cycle is larger than that of ordinary ground motions,and it is easy to cause super high-rise structures with the same natural vibration period.Resonance reaction.(2)In this paper,the finite element analysis software ETABS is used to establish a finite element model of a super high-rise concrete filled steel tube frame-core tube structure with a natural vibration period of more than 3.7s.First,the basiccharacteristics of the model are analyzed,and then five are selected from the established seismic wave database.There are 7 types of ground motions,and the elastic and elastoplastic dynamic time-history analysis of the basic structure and the damping structure at the level of frequent earthquakes and rare earthquakes respectively.Compare and analyze the seismic response characteristics of the structure such as displacement,acceleration and internal force.The results show that the structural response of the structure under five different types of ground motions is different.Among them,the structural response is the most prominent under the far-field harmonic motion,and the structural response is relatively small under the general ground motion.Under the action of three types of long-period ground motions,the maximum displacement angle of the structure will gradually move to the lower part of the floor,and at the same time,more plastic hinges will appear on the top of the floor of the structure,and the structural members will be seriously damaged,affecting the normal use of the structure.