Abstract
Many earth structures such as railway embankment are damaged by the Tsunami generated by Pacific coast of Tohoku Earthquake. These damages were mainly caused by the prolonged overtopping of Tsunami. However, the detail mechanism of the erosion of embankment body as well as the influence of the erosion of supporting ground to the entire stability of the embankment have not been understood. In this study, therefore, a series of hydraulic model tests which imitates the prolonged overtopping phenomenon were carried out. The experiment revealed that the erosion speed decreased by arranging geotexile in the embankment. Furthermore, partial ground improvement can effectively decrease the influence of supporting ground erosion to the stability of embankment
