Lead rubber bearing, applied to building and bridge constructions, is a practical and cost-effective choice for seismic isolation. It is composed of laminated elastomeric bearing pad, top and bottom sealing & connecting plates and lead plug inserted in the middle of the bearing as shown in the following picture.
During the earthquake, the un-isolated building will vibrate back and forth in varying directions due to the inertial forces and result in deformation and damages of the building. In contrast, the base isolated building will also displace but remains its original shapes and avoid damages - that is because the lead rubber bearing effectively dissipates the inertial force upon the building, extends the building’s period of vibration and decrease the acceleration of the building.
The lead plug will slid with laminated rubber during earthquake but convert this energy of movement to heat so that it efficiently reduces the inertial force upon the building, which slow the vibration of the building. Meanwhile, the rubber part will preserve its original shape due to high elasticity.