Multi-level stiffness property and isolating-based design of high damping rubber bearings

This study presents the development and analysis of high damping rubber bearings (HDRBs) with enhanced stiffness properties to improve seismic isolation performance. The proposed HDRBs exhibit displacement-dependent nonlinear stiffness and significant damping effects, especially under large deformations caused by various seismic events. A deformation history integral model, calibrated with experimental data, is employed to accurately simulate the mechanical behavior and stiffness-damping characteristics of the HDRBs. The numerical simulations are validated through experimental tests, providing a solid basis for parameter design and performance assessment. The results show that the equivalent stiffness coefficient of the HDRBs increases with deformation amplitude, effectively limiting extreme deformations. Parametric analyses and case studies across a wide range of earthquake scenarios demonstrate that the enhanced stiffness and high damping effects of HDRBs significantly improve seismic isolation efficiency while controlling isolation layer displacement. The performance-based design methodology developed in this research effectively limits bearing deformation, thereby preventing potential superstructure failures. Moreover, the adaptive characteristics of the HDRBs allow for the adjustment of deformation levels according to seismic intensity, ensuring the structural safety of buildings under varying earthquake conditions.