Abstract
Many bridges were washed away by tsunami caused by the 2011 Great East Japan Earthquake. We carried out the field survey and analyzed the damage condition of Koizumi Bridge in Mimamisanriku-cho, Miyagi prefecture. Further by using β, which is the ratio of girder resistance and wave acting force , the flow conditions of 12 tunami-dameged bridges were justified without considering the buoyancy and good evaluation of damage ranks was got. However, the damage rank evaluation by the uplift from experiment cannot good correlation with actual tunami-dameged bridges.
