Experimental validation of durable silicone elastomers for high-ductility seismic isolation bearings

Abstract Although laminated elastomeric bearings are integral components in seismic isolation systems, their elastomeric materials remain susceptible to environmental degradation and temperature-induced aging. Silicone elastomers, with their chemical inertness and long-term environmental resilience, offer a compelling alternative, yet their use in seismic isolation remains largely underexplored. This study experimentally validates the suitability of silicone elastomers as durable substitutes by benchmarking their mechanical performance against well-established standards. Concurrently, the influence of crosslinking agents on mechanical response, and the effect of bearing geometry on shear performance, were systematically evaluated. To these ends, a comprehensive experimental program was conducted: Shore A hardness and uniaxial tensile tests to characterize material stiffness and ductility, and quasi-static shear tests on reduced-scale bearing prototypes to assess shear performance under combined compression and cyclic shear loading. The results demonstrate that the tested silicone formulations satisfy all relevant thresholds for seismic isolation applications. Furthermore, the choice of curing agent modulates the trade-off between stiffness and damping capacity, whereas bearing geometry exhibited negligible influence on the overall shear response. These findings position silicone elastomers as high-performance materials with tunable properties, paving the way for their integration into next-generation earthquake-resilient infrastructure.