Simplified methodology for estimating seismic coefficients for the pseudo-static slope stability analysis of earth dams

Abstract

This paper presents a simplified methodology for the estimation of seismic coefficients for pseudo-static slope stability analysis of earth dams and tall embankments. This methodology is based on a statistical analysis of numerical results from 110 non-linear seismic response analyses of 2D cross sections with height ranging from 20 to 120 m. The peak value of the seismic coefficient is estimated as a function of: (a) the peak ground acceleration at the free field, (b) the predominant period of the seismic excitation, (c) the nonlinear (first) eigen-period of dam vibration, (d) the stiffness of the foundation soil, and (e) the geometrical characteristics and the location (upstream or downstream) of the failure surface. The effective value of the seismic coefficient is estimated as a percentile of the peak ground acceleration, on the basis of the allowable permanent seismic displacement. © 2011 Taylor & Francis Group.