Effect of void ratio on soil-water retention curves of silty sands using a pore network model derived from sphere packs

This study explores the effect of void ratio on soil-water retention curves (SWRCs) in silty sands and sands using a pore network model (PNM) applied to artificial sphere packs. This method enables a detailed analysis of pore size distributions and their evolution with changing void ratios, offering mechanistic insights into SWRC behaviour. Soil samples are modelled as sphere packings generated via a discrete element method (DEM), with pore spaces represented as networks of pore bodies connected by pore throats. SWRCs are determined by applying capillary pressures to the pore network. The model is validated against experimental data from the literature before being applied to study the effects of void ratio on SWRCs. The simulation results provide insights into how microstructural characteristics evolve with changes in soil void ratio, leading to variations in the air entry value and the slope of the SWRC.