Abstract
To estimate the fragility of wooden buildings (houses) in relation to the tsunami water depth and hydrodynamic force during the 2011 Great East Japan tsunami, a numerical simulation was conducted in two different regions using a nonlinear long wave equation model that includes the breaking or washout condition of trees and houses, and trapping function of driftwood by coastal forest. Fragility curves as a function of water depth, fluid force and moment by fluid force were analyzed for different level of house damages. Some differences exist especially for the fragility curve of washing out houses, but the curve has been improved by considering the trapping effect by trees, and become similar to that in the region where coastal forest was thin and breaching of embankment was not occurred.
