Theoretical soil water characteristic curves for large graded soil

The present study is focused on a theoretical model of unsaturated soil based on elastic spherical particle arrangement, which can be considered to be a simplified DEM method. The model is presented with a large graded soil. This approach follows a new research method so that the physical phenomena are explained and the number of experimental parameters is limited. The theoretical model takes into account the different arrangements of soil particles so that the entire void ratio scale is covered. The wetting and drying paths are modelled. A comparison with the Brooks and Corey (1962) theory and the new theory is achieved on experimental results with a sample of glass micro-sphere and two natural soils, the Livet-Gavet sandy-loam and the Livet-Gavet loam. It shows that this new theory improves precision of the prediction using only simple physical parameters.