Behavior of RC Structures Under Tsunami Triggered by The Great East Japan Earthquake

SUMMARY: Type The Great East Japan Earthquake on March 11, 2011 is the most powerful know earthquake that has hit Japan with a magnitude of 9.0 and epicentre at 129 km of Sendai city of the Tohoku region (East-North region of Japan). The earthquake triggered destructive tsunami with run up height of up to 38 meters that affect mainly cities located on the Pacific Ocean coast of the Tohoku region. In general the wooden structures were destroyed completely by the tsunami when the water depth reached or exceeded the first floor height. The steel (frame) structures did not collapse in general by the tsunami action however heavy damages of walls, panels, ceilings and other non-structural elements were observed. Reinforced concrete buildings did not collapse in general and resist better the action of the tsunami however, non-structural components were severely damages. In this report the characteristics of the damages and behaviour of RC buildings during the tsunami action is discussed based on the field survey of damages in some cities located on the coast of the affected zone. The analysis has permitted to understand the behaviour of this kind of building and some recommendations are obtained for their use to take refuge from the tsunami in places where natural topography make impossible to reach hilltops or other safer places.