Design And Research Of Seismic Isolation Scheme For A Large Irregular Structure

With the continuous development of national economy and science & technology,the functions of engineering structures are increasingly diversified.In order to meet the diversified functional needs,engineering structures with irregular shapes and uneven stiffness are increasingly appearing in our life.Due to its own structural characteristics,the mass center and stiffness center of irregular structure do not coincide,which leads to the damage degree of irregular structure is much greater than that of regular structure under the action of earthquake.Therefore,it is necessary to adopt certain measures of shock absorption and isolation for irregular structures.The application of seismic isolation technology can effectively reduce the seismic response of irregular structures,so as to improve the safety and stability of irregular structures.This paper takes a large irregular structure under construction as the research object,and uses Midas/Civil software to analyze the dynamic time-history of large irregular structure under frequent earthquakes and rare earthquakes.In this paper,four kinds of isolation bearings are added to the structure,which are widely used in engineering,and the effect of different types of isolation bearings on the large irregular structure is analyzed,and the optimal design of the layout of the isolation bearings is put forward.The research results show that:1.Due to the uneven distribution of mass stiffness of large irregular structures,the seismic response of each block of the structure varies greatly under the earthquake action,and the maximum internal force,maximum stress and maximum displacement of the structure are concentrated in several key parts.The overall seismic response is large,so it is necessary to adopt certain seismic isolation measures for large irregular structures.2.In this paper,four kinds of isolation bearings which are widely used in engineering are selected and added to the large irregular structure respectively.The four kinds of bearings have certain effect of shock absorption and isolation,but under different structure position and earthquake action,the four kinds of bearings have different effect of shock absorption and isolation.Based on the results of dynamic time-history analysis,the arrangement scheme of lead-core rubber bearing is the most suitable one for the large irregular structure.3.In this paper,two kinds of optimization schemes are proposed for the layout scheme of single isolation bearing.The main optimization effect of the internal force control optimization scheme is that the maximum displacement control effect of the superstructure is superior to that of the single steel damping bearing layout scheme.The integrated control optimization scheme effectively optimizes the smoothness of the internal force reduction rate curve under the action of multiple earthquakes and rare earthquakes.Both of the two optimization schemes have an optimization effect on the single isolation bearing system,but by comprehensive comparison,the comprehensive control optimization model is better.