Experimental and consolidation modeling of flowing mud during vacuum preloading considering transient clogging and vacuum pressure attenuation

The non-uniform dense soil column that forms around plastic drainage plates when using vacuum preloading to treat flowing mud exhibits varying clogging along the extension direction, which severely lowers both the consolidation effectiveness and rate of consolidation. A transient clogging model is established based on indoor tests conducted under varying vacuum pressure for analyzing the evolution and impact of soil column along the plastic drainage plate direction. The study reveals that the vacuum pressure attenuation alters soil water content, density, and permeability, resulting in the formation of a “carrot-shaped” clogging zone, which adversely affects the drainage rate and consolidation uniformity. Building on the transient clogging model, a vacuum consolidation analysis method is proposed taking into accounting for the nonlinear vacuum transfer and soil characteristics. The validity of the proposed method is confirmed through case studies, accompanied by a detailed parameter analysis and discussion.