scope:

This International Standard describes the international common principles regarding the design of seismically isolated structures under earthquake effects. Since proper construction management and maintenance are important for realizing high quality seismic isolation structures, this standard also describes the principles of construction management and maintenance that the designer should consider. The seismically isolated structures targeted by this standard have the seismic isolation interface applied between a superstructure and a substructure. Isolation devices are installed in the isolation interface to reduce the effect of the earthquake ground motion onto the superstructure. The isolation devices consist of isolators and dampers. Some types of devices can function as both isolators and dampers. This standard mainly focuses on seismic isolation of buildings. However, the guidelines are useful for bridges, LNG tanks and other structural types as well. In most cases, the substructure refers to the foundation of the structure. However, the substructure in this document consists of a structural system below the isolation interface that has been designed with sufficient rigidity and strength. Examples include locating the isolation interface in a mid-storey of the building or above the bridge piers. This standard mainly specifies seismic isolation structures that attenuate the horizontal response of a structure to horizontal earthquake ground motions. Seismic isolation to reduce the vertical response is excluded.