Modelling the effect of density on the unimodal soil-water characteristic curve

Research has shown that the soil-water characteristic curve (SWCC) is dependent on the density of the soil; therefore, using a single SWCC based on one density is insufficient to describe the SWCC of soil in the field, which may have significant density variation. In order to take into account the effect of density on the SWCC, soils of different densities need to be tested, and this is impractical. In this note, an equation which can account for the effect of density on a unimodal SWCC plotted in terms of gravimetric water content by determining only one SWCC is proposed. The proposed equation was verified using data from this study as well as other published data.