Seismic Performance Analysis Of Frame Structures Using Seismic Isolation Technology

Building isolation is an isolation technology which usually sets up an isolation device at the bottom of structures or between layers of the upper floors.Building isolated structure system is a passive control system which is different from the traditional anti-seismic structure,and it can absorb the seismic energy input and consumption through the isolation layer of the isolation bearings to reduce the structural seismic response of the earthquake.With the development and improvement of the isolation technology,it brings new ideas and methods to the field of earthquake disaster reduction for the engineering development.The isolation technology is divided into base isolation and story isolation.With the deep research of the base isolation technology,it has formed a complete set of theory and has been widely used in the actual project.Based on this point,through the theoretical derivation and numerical simulation analysis of the shock damping effect of base isolation,and by comparing with the traditional anti-seismic structure,this thesis makes a comparative study of the similarities and differences of the two in the frame structure of the isolation performance.In this paper,the mechanical properties of rubber bearings are analyzed,and the equivalent analysis model of rubber bearings is studied and established.In this chapter,the vibration differential equation of base-isolated structure system is deduced.We have a deeper understanding of the working mechanism and isolation principle of the base isolation structure system,and have made a theoretical preparation for the application of the base isolation technology in practical engineering.In this paper,the SATWE model and ETABS base isolation model of frame structure are established,the acceleration and displacement responses of frame structure with base isolation under earthquake are calculated and deduced,and the dynamic characteristics,mode shapes and periods of these results are studied.The time history analysis method is used to compare the calculation results of base isolation and non-base isolation.The performance characteristics of the two structural models and the variation law of seismic response are expounded.The two models are basically identical in terms of mass,period and inter-story shear force.The natural vibration period of frame structure is significantly prolonged and far away from the basic period of structure after using base isolation technology.By checking and calculating the parameters of bearing pressure,tensile stress,eccentricity and deformation,it can be seen that the isolation bearing arrangement is reasonable and the isolation layer has high reliability and stability.The average value of the maximum seismic response under the action of seven time-history curves is used as the final calculation value of time-history analysis.The results are reliable and can be used in engineering design.The seismic energy of the incoming superstructure decreases significantly,and the response of floor acceleration,floor shear and floor displacement is significantly lower than that of the non-isolation frame structure,and the isolation effect is obvious.In this paper,the influence of structure quality,horizontal stiffness of isolation layer and parallel isolation system on the seismic absorption effect of isolation structure is studied.The period after isolation,the displacement of isolation layer,the acceleration of structure and the horizontal damping coefficient allincrease with the increase of structure quality,and the effect of vibration reduction decreases.With the increase of the number of sliding bearings,the horizontal stiffness and acceleration of the isolation layer decrease,the period and displacement of the isolation layer increase,the horizontal damping coefficient decreases and the effect of the isolation increases.The research results show that base isolation have a very significant shock damping effect.Meanwhile,acceleration of the upper structure and lower of the shock-layer structure interval,the floor displacement and shear have different trends.and the isolation of different parameters of the structure of the dynamic response will produce certain impact.