Frequency based damage identification of laminated rubber isolation bearing

A damage identification method of laminated rubber bearing based on its natural frequency is proposed in this paper. Through the periodic structural characteristics of laminated rubber bearings and the characteristic waveguide nano method of the periodic structure,the relationship between the natural frequency and the change of overall shear modulus of the basic periodic unit is deduced,and the sensitivity identification equations of the rate of natural frequency change to unit damage is established. The identification equation set is solved by the constrained optimization method. The damage identification of the laminated rubber isolation bearing based on the change of natural frequency is therefore realized. The example of the calculation model considers the influence of the upper structure on the rubber bearing at the bottom layer,which makes the calculation model more in line with practical engineering. The effectiveness and accuracy of the damage identification method proposed in this paper is verified by the three-dimensional finite element numerical siulation analysis. © 2024 Nanjing University of Aeronautics an Astronautics. All rights reserved.