EFFECTS OF SOIL NON-LINEARITY ON THE SEISMIC DISTRESS OF RETAINING WALLS

摘要

Despite the structural simplicity of retaining walls, their seismic response is a rather complicated problem. What makes that response so complicated is the dynamic interaction between the wall and the retained soil, especially when material and/or geometry non-linearities are present. This paper aims to examine how and to what extent the potential soil non-linearity may affect both the dynamic behavior of a rigid non-sliding retaining wall and also the seismic response of the retained soil layer. For this purpose an extensive parametric study, based on two-dimensional dynamic finite-element analyses, is conducted. Soil non-linearity is realistically taken into account via a computationally efficient equivalent-linear procedure. The examined numerical model is studied under different excitations and various levels of the imposed ground motion maximum accelerations to examine more thoroughly the influence of material non-linearity. The results of this study justify the hypothesis that the non-linear soil behavior has a considerable impact not only on the dynamic earth pressures developed on the wall, but on the amplification of the acceleration levels on the backfill soil as well. Therefore, it becomes evident that seismic codes and geotechnical design practice should take this impact into serious consideration.