Abstract:
Soil – water characteristic curve (SWCC) is an important property of unsaturated soils that can
be used to estimate various parameters to describe unsaturated soil behavior. SWCC is reported to be
hysteretic because the water content at a given suction in the wetting process is less than that in the drying
process. In order to simulate the hysteretic characteristics of SWCC, many models have been proposed by
different researchers. However, majority of the existing models are complex and their parameters are not
related to the physical significances of SWCC variables. In this study, the new equations are developed to
model drying and wetting SWCC. In addition, some indexes are proposed to estimate the wetting SWCC
from drying SWCC. The new equations for SWCCs were evaluated with the laboratory data from published
literatures. The results showed that the proposed equations performed well in modelling drying and wetting
SWCC. The new equation has less parameters than the existing published equation