Centrifuge model tests on the dynamic response of slopes subjected to water storage at the toe area

Abstract

Stability of slopes where water was accumulated at the toe area during dynamic events were studied in this paper. The soil below and right above water level tended to be contractile and loose due to water storage at the toe of slope, and the slope behaviors became different compared with those without water storage. Several model tests in a geotechnical centrifuge were carried out in this paper to examine the effects of water accumulation at slope toe, relative density of soil, and shaking intensity of dynamic events on the slope stability. The compression of the soil below the water level and localized failure at the toe region subjected slopes to more shearing during shaking and potentially large movements. For the unsaturated slopes with high suction, total collapse was not possible even in model where intense shaking was excited. Successive shaking with increasing intensities could cause more cracks on the surface of the slope, and the deep and wide cracks were mainly on the upper middle part of the slope. Cracks concentrated at areas near the water level. Seepage and capillary flow are two factors that need further attention in the study of the dynamic response of unsaturated slopes with water storage at toe.