Abstract
A method to evaluate permanent deformation of an embankment and a slope is proposed, in which spatial distribution of shear strength and amplification characteristics of the earthquake motion in the embankment/slope are considered. This method is composed of two procedures to evaluate a critical slip surface and permanent deformation. A method is proposed to evaluate critical slip surface of multi-layered embankment as logarithm spiral shape. The Newmark's method is improved in order to consider the effect of amplification of the earthquake motion in the embankment by employing the energy principle; the conventional Newmark's method is expressed to be a case with rigid body motion of the sliding mass. The method is applied to the slope failure of the river dike of the Naruse river, Kimasuka district during the 2003 Northern Miyagi Prefecture earthquake and good agreement is obtained with the observed damage.
