Fine Grain Dispersion Behavior in 3D Spherical Packing-Numerical and Experimental Investigations

Abstract Suffusion-induced loss of fine grains can induce mechanical instabilities in granular soils. A conceptual countermeasure could be the re-injection of fines from upstream to induce clogging in the soil matrix as a remediation method. This work attempts to study the dry and fluid-driven infiltration behaviors of fine sand in granular columns from numerical and experimental aspects. The base soil used in this work adopts the particle size distribution (PSD) of typical Hostun Sand HN1/2.5 mm. Different governing factors, such as size ratio R , base soil packing density, particle morphology (angular Hostun 1/2.5 and spherical glass beads) and flow conditions (operated by peristaltic and gear pumps), are analyzed. The results from numerical and experimental aspects on the fine retention distribution within coarse grain matrix are compared and a simple probabilistic model based on pore-constriction size statistics is put forward to interpret the clogging distributions.