Research On Calculation Method Of Eccentricity Of Seismic Isolation Layer Of Isolation Structure Considering Effective Stiffness Correction

In order to solve the problems of the existing calculation method of the isolation layer eccentricity of the isolation structure,the physical concept is not clear,the effective rigidity of the isolation support is unreasonable,and the effective rigidity of the isolation layer damper is not considered,eccentricity calculation method considering effective stiffness correction is proposed.This article uses a combination of theoretical analysis and numerical simulation to systematically compare the proposed eccentricity calculation method considering effective stiffness correction.The main research contents and research conclusions are as follows:(1)In view of the unclear physical concept of the existing isolation layer eccentricity calculation method,the theoretical derivation and physical significance comparison analysis of the existing eccentricity calculation method and the proposed eccentricity calculation method considering effective stiffness correction are carried out.The research results show that the physical meaning of the effective stiffness of the bearing in the existing calculation method of eccentricity is not clear.Considering the effective stiffness correction eccentricity calculation method corrects the effective stiffness of the support and the damper,the calculation formula can reflect the difference in the stiffness of each support caused by the torsional deformation of the isolation layer.(2)Research on the dynamic stiffness of the isolation support of the isolation structure and the dynamic eccentricity of the isolation layer.The results show that the isolation structure has different displacements due to eccentric torsion and different bearing placement.(3)Aiming at the analysis of vibration response spectrum of seismic isolation structure,the specific application of eccentricity calculation method considering effective stiffness correction under response spectrum is studied.The parameter analysis model and the actual engineering model are compared with the existing methods by using the effective stiffness correction method.The research results show that the proposed eccentricity calculation method can truly reflect the stiffness distribution of the bearings of the isolation layer.(4)For the time-history analysis method of isolated structure,the specific application of the eccentricity calculation method considering effective stiffness correction under timehistory analysis is studied.The parameter analysis model and the actual engineering model are compared with the existing methods by using the effective stiffness correction method.The results of the study show that: combined with the numerical results and the comparative analysis of the physical meaning,the proposed eccentricity calculation method truly reflects the difference in the effective stiffness of the bearings of the isolation layer.(5)For the combined isolation structure,the specific application of the calculation method of eccentricity considering effective stiffness correction in the isolation layer is studied.The parameter analysis model and the actual engineering model are compared with the effective stiffness correction method and the existing method without considering the effective stiffness of the damper.The results show that after considering the effective stiffness correction of the isolation layer damper,it can more truly reflect the overall stiffness distribution of all supports and dampers of the isolation layer.