Centrifuge Tests of Geocell-Reinforced Retaining Walls at Limit Equilibrium

Abstract

The failure modes of geocell-reinforced retaining walls differ from those of rigid retaining walls, for which only limited information is available in the literature. In the present study, a series of centrifuge model tests was carried out to investigate the performances of geocell-reinforced retaining walls at limit equilibrium under various conditions. Digital image analysis was employed to determine the displacement vectors of soil and geocell-reinforced soil, which were used to obtain the failure surface and g-level at limit equilibrium. The effects of the geocell pocket size, geocell layer height, geocell membrane tensile stiffness, and backfill surface loading location on the stability and failure mode were investigated. In addition, the preferred layout of geocell-reinforced sections, additional reinforcement layers, and two-tiered geocell retaining walls were studied. The test results indicate that the stability of geocell-reinforced retaining walls could be improved by reducing the spans between the welded spots of geocells, increasing geocell-membrane stiffness, and connecting additional geogrid layers to geocell walls. Two-tiered geocell retaining walls performed better than single-tiered ones at the same height. It was also found that the limit equilibrium method for slope stability analysis may be employed to predict the stability and critical failure surfaces of geocell-reinforced retaining walls. Some limitations of the present study are also discussed.