Centrifuge Modeling of Drying-Wetting Cycle Effect on Soil Slopes

A group of well-designed centrifuge model tests were conducted to analyze the influence of drying-wetting cycles on the failure and deformation behavior of the slope. The full-field displacement was measured via the image correlation-based analysis and was used for the coupled analysis of the deformation and failure process. The drying-wetting cycles caused the slope to exhibit a shallower slip surface and lower safety limit. The drying-wetting cycles induced a remarkable progressive failure downward to the toe of the slope that was driven by the coupling development mechanism in the local failure and deformation localization of the slope. The slope deformation tended to localize in an area and then was aggravated, which led to the local failure there. The derived progressive failure mechanism highlighted the diversity in the slip surface and safety limit of slopes with the application of various water variation conditions. The drying-wetting cycles decreased the slope stability by aggravating the degree of deformation localization. The drying-wetting cycles induced significant deformation near the slope surface, where the direction of slope displacement exhibited a reversible change within a drying-wetting cycle and changed from vertical to horizontal as the elevation decreased. The drying-wetting cycle caused the soil to consolidate; therefore, the slope deformation that was due to the drying-wetting cycles decreased as the number of drying-wetting cycles increased.