Report on the effects of seismic isolation methods from the 2011 Tohoku–Pacific earthquake

Abstract

The earthquake that occurred on March 11, 2011 off the Pacific Coast of Tohoku caused devastating damage to the northeast Pacific coast region of Japan.We discuss the response to this earthquake of three buildings in Shimizu Corporation's Institute of Technology in Tokyo, each with a different type of seismic isolation, and that of a test building for seismic isolation jointly built by Shimizu Corporation and Tohoku University on the Sendai campus in Miyagi prefecture, which was near the earthquake's epicenter.The effects of seismic isolation methods were verified through the observed earthquake responses of the four buildings.In each of the three seismic isolated buildings at the Institute, the observed accelerations on the floors were reduced to about half compared to those on the ground.In the test seismic isolated building in Tohoku University, the observed accelerations on the roof were reduced to about one third compared to those in an adjacent conventional seismically designed building.