Analysis of Permanent Deformation of Earth Dams Due to Earthquakes

Abstract

A methodology to assess the permanent deformation of earth fills such as dams and embankments subjected to a shaking of an earthquake is presented. The method consists of a. hybrid use of the static and dynamic response analyses and the laboratory soil tests by means of the triaxial torsion shear test apparatus. The static as well as dynamic analysis are made first using the finite element method to obtain the initially applied static stresses and also the time histories of shear stress during an earthquake. The tests are performed by applying the time histories of three components of dynamic stress plus the static state of stress thus obtained to the representative samples placed in the test apparatus. The residual strain potential obtained from the tests is incorporated into the static analysis to evaluate the final configuration of the earth fills deformed by the earthquake shaking. This methodology was applied to assess the seismic behavior of an earth dam in Japan.