Seismic Isolation Bearings
Seismic isolation is a technology that protects the structure from the destructive effects of an earthquake. The seismic isolation bearings decouples the structure from the ground and provides it with damping. This decoupling allows the building to behave more flexibly which improves its response to an earthquake. The added damping allows the earthquake energy to be absorbed by the isolation systems and therefore reduces the energy transferred to the structure. Seismic isolation is physically achieved by placing the structure on isolators. The isolators are laterally flexible elements, yet they are able to carry the vertical loads of the stucture. Since the isolators are more flexible than the structure, most of the lateral movements occur in the isolators. As a result the isolated structure experiences less motion and reduced forces.
Seismic isolation provides superior performance compared to a traditional structural design. It reduces the forces and displacements in the structure by up to 75%. The isolation system accomplishes this by deforming laterally during the earthquake. After the earthquake this results in a functional structure with little or no damage.