Comparative Study And Parametric Analysis Of A Building Base Isolation Scheme And Interlayer Isolation Scheme

With the development of isolation theory and isolation technology,the performance of isolation structure is more and more remarkable.In the process of the development and maturity of the base isolation technology,the interlayer isolation technology,which is an extension of the base isolation technology,has been more and more recognized by people.In the current code of our country,it is stipulated that the isolation layer of the isolation structure should be set at the top of the foundation.However,in practical engineering,due to the limitation of topographic conditions and architectural functions,it is difficult to meet the requirements of norms,which has brought some limitations to the construction of buildings.Therefore,to break through this limitation,it is necessary to consider setting the isolation layer in a certain layer of the topside structure,which forms a new isolation system-the interlayer isolation system.The greatest advantage of the system is that it is more flexible in the selection and arrangement of isolation layers.Taking an eight-layer frame concrete structure as an example,this paper makes a comparative study of the base isolation scheme and the interlayer isolation scheme respectively.SAP2000 analysis software was used to establish five structural models inclouding non-isolation structure,base isolation structure,2nd layer column top isolation structure,4th layer column top isolation structure,and 6th layer column top isolation structure,respectively,and to conduct nonlinear time history analysis and energy method analysis.The analysis shows that isolation layer position is different,the structure of isolation performance is different also.Among them,the base isolation structure and the 2nd layer column top isolation structure have excellent isolation performance,which also indicates that the isolation layer position is set low and its isolation effect is better.Finally,the parametric analysis of the isolation structures is carried out.Based on the analysis of the horizontal stiffness parameters of the isolation layer,it is concluded that when the location of the isolation layer is set at a low level,the seismic response of the structure increases with the increase of the horizontal stiffness of the isolation layer,and the variation amplitude is large.When the position of the isolation layer is set high,the seismic response of the structure is little affected by the horizontal stiffness of the isolation layer,and the horizontal stiffness of the isolation layer does not play a major control role.When the horizontal stiffness of the isolation layer remains unchanged,the seismic response of the structure decreases with the increase of the layer.Based on the analysis of damping ratio parameters of isolation layer,it is concluded that the seismic response of the structure decreases with the increase of damping ratio of isolation layer.For the same isolation structure,the seismic response of the topside structure decreases with the increase of the layer under the condition of constant isolation layer damping ratio.