Abstract
Centrifuge shaking table test with 30G of the acceleration of gravity is conducted in order to clarify the failure mechanism of the earth structure under the unsaturated condition. A soil structure model composed of an embankment with sandy soil, a foundation ground, and a base layer. Four earth structures models are tested, in which moisture condition in the embankment and liquefaction of the foundation ground are chosen as test parameters. The observed record at the river dike during the 2003 Northern Miyagi Prefecture earthquake was used as an input wave. It is found that slope failure occurred in the unsaturated embankment because of excess pore water pressure generation, whereas it does not occur in the dry embankment. The process of excess pore water pressure generation depends on the permeability of the foundation ground.
