CASE STUDIES FOR EARTHQUAKE-INDUCED PERMANENT DISPLACEMENTS OF EMBANKMENT SLOPES

Abstract

A methodology proposed by the authors to evaluate earthquake-induced permanent deformation of embankment slopes is briefly presented. In this method, a finite element seismic analysis and dynamic programming are combined to determine critical slip surfaces within a slope during an earthquake. Then, a modified Newmark procedure is proposed to evaluate seismic displacements of slopes by considering variable critical slip surfaces. The methodology is used to analyze an embankment slope with a thin weak layer and a large-scale embankment slope in Japan which suffered severe damage during the 1978 Miyagiken-oki Earthquake. Results show reasonably good agreement with the permanent displacements obtained from a nonlinear FEM analysis.