SEISMIC RISK ASSESSMENT OF FILL DAMS CONSIDERING EARTHQUAKE-INDUCED SLIDING DEFORMATION

Abstract

In this paper a methodology on seismic risk evaluation of fill dams is proposed, where sliding displacement of the soil mass along the failure surface is considered with Newmark sliding block model. The feature of this study is the probabilistic evaluation of the seismic risk. Considering variabilities of sliding displacement, fragilities of various types of fill dams are evaluated defined as the conditional probability of exceeding allowable displacement of the sliding mass for given intensity of the ground motion. With the fragilities and the seismic hazard, annual probabilities of failure of the fill dams are calculated showing the seismic risk level of the existing fill dams designed by conventional design method is of the order of 10^-5 or less and comparable with or less than other important civil engineering structures.