A study on mechanical properties of variable stiffness rubber bearings based on the stiffness matrix analysis method

A new type of variable stiffness rubber bearing suitable for isolating three-dimensional earthquake or vertical vibration was proposed on the basis of the mechanical behavior of the rubber bearing, and the stiffness matrix analysis method that can solve the mechanical problem of non-homogeneous body of the variable stiffness bearing was described. Firstly, based on the analytical solution of the commonly used rubber bearing and the nonlinear response analysis of the compression shear test, the stiffness matrix analysis was used to calculate the test bearing, and the results are highly consistent with the test values, which verifies that the calculation accuracy of the method is high. Then, the results of the three kinds of bearings were compared: under the same external load and material parameters, the force and deformation of the thick bearing are the largest, and the force and deformation of the variable stiffness bearing and common bearing are significantly lower than that of the thick bearing; under different axial pressures, the P Δ effect is manifested as follows; the force and deformation of the thick bearing and the horizontal stiffness are most significantly affected by the axial pressure, while the variable stiffness bearing and the common bearing are less affected by the axial pressure. Finally, the calculation example shows that the vertical stiffness can be optimized by adjusting the variable stiffness bearing. In conclusion, the variable stiffness bearing has a better bearing capacity for force and deformation, and provides a simple and practical solution for three-dimensional seismic isolation ( vibration ). © 2024 Chinese Vibration Engineering Society. All rights reserved.