Analysis Of The Impact On The Structural Seismic Performance Of Isolation Layer Position

With the development of isolation technology,the structure with isolation shows obvious advantages in anti-seismic performance.However,because of the limits of base isolation technology,it has been unable to meet the needs of all the engineering practice.So story isolation technology is proposed.The development and application of story isolation technology widen its scope in engineering.And meanwhile it solves the limitation of base isolation technology,which can be applied to vertical irregular structure,reinforcement of old buildings and the structure restricted by terrain conditions that cannot apply the base isolation technology and so on.The location of the isolation layer in the practical engineering for their design,or different Settings in different locations cause accordingly seismic performance changes and produce different damping results.So this is studied in this paper.This paper makes a brief overview of related concept of the base isolation and the story isolation,and then discusses the frame structure of base isolation by finite element analysis software SAP2000 using it to design and analyze.Then four finite element model set up with SAP2000 respectively assign the isolation layer in base,1st,3th and 5th story based on a seven layer reinforced concrete frame structure.Then time history analysis under the earthquake intensity and static nonlinear analysis under rare earthquake both used in order to compare the inter layer shear force,displacement between layers.And the seismic performance control isolation layer structure stress and deformation characteristics in different locations can be mastered.Therefore the different design plan can be provided for the designers.Finally,based on the layer seismic interval technique in an engineering example,the application proves that it has excellent seismic performance.At the same time,the example also explains the layer interval seismic technology can be practiced in engineering.Studies have shown that compared to the traditional anti-seismic structure,setting up the isolation layer in structure has more significant damping effect.The deformation of isolation layer in the earthquake will dissipate the energy,what's more,reduce the earthquake energy of structure upward transmission.So it can achieve the purpose of the isolation structure damping.Meanwhile the isolation layer position set up differently can be influenced the seismic performance of frame structure obviously.In general,the lower isolation layer position is better than the upper ones in dissipation of energy.The base isolation structure is superior to all inter-story isolation in shock absorption effect.Isolation layer is situated in the fifth storey,the structure of the damping effect is significantly below the isolation layer in the first and the third floor,so when using seismic technology layer interval,suggest setting the isolation layer of lower position.