Design and modeling of intelligent shock isolation bearing based on negative stiffness platform

In this paper, an intelligent shock isolation bearing based on the negative stiffness platform (SIBP) is designed, manufactured, and modeled. The addition of the negative stiffness platform to the SIBP can further reduce the natural frequency of the structure and enable the isolator to a broader range of isolation frequencies. It is noteworthy that the stiffness of the magnetorheological elastomer (MRE) limit layer can be adjusted to provide controllable seismic resistance and to achieve isolation and vibration reduction under various seismic conditions, such as small and large displacements. Through the theoretical analysis and magnetic field simulation of the SIBP’s damping force, the structure of the SIBP is designed and established. Then, the MRE for the SIBP is prepared. The shear storage modulus and damping factor of MRE with different strains are tested and analyzed. A novel dynamics model is established to model the displacement–force hysteretic curve of the SIBP under small displacement and large displacement input. The experiment results show that the theoretical calculation results are in good agreement with the actual shock isolation bearing, and the proposed model can accurately describe the dynamic characteristics of the SIBP, which provides the design basis for the application of the SIBP in active control.