In order to investigate the input mechanisms for seismic motion in buildings, we need to conduct a comprehensive observation of buildings and the surrounding ground. The BRI Urban Disaster Mitigation Research Center (annex) building was densely instrumented, as shown in the figure below, to allow measurements related to the local site effects, SSI effects, and response of the building to be thoroughly ascertained.
The recording system has eleven sensors (33 channels) in the annex building, seven sensors (21 channels) in the surrounding ground, and four sensors (12 channels) in the main building. The annex building is a steel reinforced concrete building with eight stories above ground and one below. The observation was started in 1998 with the completion of the building. A great number of records have been accumulated to date with useful fruitage obtained.