Modelling of hysteresis response for arbitrary wetting/drying paths

Both empirical and theoretical (thermodynamic) investigations indicate that the soil-water characteristic curve (SWCC) is an essential element in unsaturated soil modeling and it is hysteretic in nature, owing to the energy dissipation during moving fluids in or out of the soil. Because of its fundamental significance, this hysteretic feature can no longer be ignored in unsaturated soil modeling. This note presents a simple phenomenological approach for modeling hysteretic SWCCs following arbitary wetting/drying paths.