Current State of Seismic-Isolation Design

Abstract

Japan has the world’s highest number of seismic-isolation structures - a figure that has been gradually increasing since the 1995 South Hyogo earthquake that devastated Kobe and its environs. It is the main reason that two seismically isolated buildings in Kobe have shown good performance during and after earthquakes. As the awareness of the benefits of seismic isolation has grown, it is being accepted more among people, to maintain structural safety and functionality during and after earthquakes. Safety, property value, and functionality must be maintained by the earthquake-resistance performance of buildings. This seismic isolation system is the appropriate earthquake-resistant method in consideration of satisfying these three items, and positive in the design of structures, such as residences, hospitals, and high-rise buildings, then in retrofitting. This paper focuses on the current status of seismically isolated structures and problems in seismic isolation design.