ABSTRACT
In previous studies the authors suggested that in the low potential (high suction) range, clay water matrix potential is due, essentially, to adsorption and not capillary effects. In many soils, the adsorption potential appears to be dominated by van der Waal forces, which are related to the specific surface area (Sa) of the clay particles. A theoretical expression for clay soil-water characteristic curves (SWCC) was consequently developed for cases in which the osmotic potential is small relative to the matrix potential, and van der Waal forces are dominant. Use of this expression requires knowledge of Sa, which is not commonly available in standard geotechnical data. The present paper presents a relation between Sa and liquid limit, based on data from the literature, and uses this relation to compare theoretical SWCC’s with measured curves presented by other researchers.
