Miniature Testing Device to Study the Effect of External Load, and Irrigation Rate and Direction on the Capillary Collapse of Unsaturated Soil

Abstract The capillary collapse is an irreversible volumetric deformation of partially saturated soils induced by an increase in the water content. While extensively studied by several authors, there remain factors yet to be explored. Based on preliminary laboratory tests, this paper proposes an experimental device to study how changes in irrigation rate, direction, and total stress on the soil specimen affect collapse behavior. This device will be used in future collapse tests during with parallel X-ray computed tomography (CT) imaging to understand the phenomenon from a microscopic approach.