Smart Lead Rubber Bearings Equipped with Ferrous Shape Memory Alloy Wires for Seismically Isolating Highway Bridges

Shape memory alloys (SMA) can substantially improve the damping capacity and re-centering capability of elastomeric isolators. The objective of this study is to assess the seismic performance of smart lead rubber bearings (LRBs) equipped with double cross ferrous SMA wires. Hysteretic shear response of SMA wire-based LRB is determined using finite element method. The seismic response of a multispan continuous steel girder bridge isolated by SMA-LRB is evaluated. Hybrid SMA-LRB bearing exhibits a significantly lower shear strain demand (up to 46% reduction) and a higher energy dissipation capacity (up to 31% increase) compared to the LRB.