MODELING AND ANALYZING OF TENSILE STIFFNESS FOR SEISMIC ISOLATED RUBBER BEARINGS

To analyze the tensile performance of seismic isolated rubber bearings, a two-spring model is established for calculating the tensile stiffness of bearings. According to the shear and tensile geometric deformation condition of the bearings, the theoretical formula of tensile stiffness are derived for rubber bearings subjected to shear and tensile loads. Based on the derived expressions, the relationship between tensile stiffness and shear deformationis is analyzed. Furthermore, the analytical results are compared with the finite element analysis results and the tensile experimental results. The results show that the tensile stiffness expressions derived in this paper can be used to simulate the tensile stiffness variations for rubber seismic isolated bearings with shear deformation less than 100%.