Development and Validation of Low-Cost FREBs Using Recycled Butyl Rubber for Seismic Isolation

This study presents the development and experimental validation of a novel, low-cost fiber-reinforced elastomeric bearing (FREB) fabricated from recycled butyl rubber (IIR) sourced from used truck inner tubes. Designed to provide an affordable and sustainable solution for seismic base isolation in developing regions, the research integrates experimental testing and finite element simulations. Compression and cyclic shear tests confirmed that the FREB achieves vertical load and stiffness performance comparable to commercial elastomeric bearings while maintaining stable hysteresis behavior and effective damping at large strain levels. Numerical simulations using ABAQUS/CAE closely matched the experimental results, confirming the validity of the mechanical model. Overall, the FREB demonstrates high load-bearing capacity, reliable horizontal response, and efficient energy dissipation, establishing it as a cost-effective and environmentally sustainable alternative to conventional elastomeric bearings.