Preliminary Reconnaissance Report of the 2011 Tohoku-Chiho Taiheiyo-Oki Earthquake

Devastating damage in the Tohoku region of Japan occurred during and after the massive earthquake off the Pacific coast, the Tohoku earthquake, on March 11, 2011. The Architectural Institute of Japan dispatched reconnaissance teams into the field to obtain basic facts on the damage to buildings due to the massive ground motions and resultant tsunami. Their mission included collecting information on the characteristics of the earthquake itself and the observed major ground motions and tsunamis throughout the area. For the investigation of structural damage, buildings are classified by their type of construction—steel buildings, reinforced concrete buildings, wooden houses, and others—along with descriptions of special features for each category of building type. This report summarizes damage associated with ground failures including landslides and liquefaction as well as nonstructural damages such as to equipment and facilities, partitioning walls and ceilings, and functional failures in skyscrapers. A brief description of the Japanese Seismic Design Code is provided in the Appendix, and a proposed scheme of anti-tsunami design for buildings is also included.