Geotechnical Engineering Journal of the SEAGS & AGSSEA ISSN 0046-5828
Vol. 50 No. 1 March 2019
Water Retention Characteristics of Swelling Clays
By Kannan R. Iyer and D. N. Singh
ABSTRACT: Initial state of soil (viz., slurried, intact or compacted state) influences the soil water retention characteristics (SWRC), which in turn affects the unsaturated soil behaviour. Few studies have investigated the effect of initial state of soil on their SWRC, and such studies are rare for swelling clays. In this context, drying- and wetting- path SWRCs have been developed, in the present study, for intact and reconstituted specimens of swelling clays, by employing Dewpoint Potentiometer (WP4C®) and Environmental Chamber in tandem. The wetting-path SWRC has also been developed by controlled water sprinkling method. From the study, influence of initial water content has been observed to be higher on drying-path SWRCs as compared to wetting-path SWRCs of the clays. Further, the drying-path SWRCs for intact and reconstituted specimens converge beyond certain stage of drying. The study suggests the utilisation of reconstituted specimens for studying behaviour of intact clays in relatively dry state.
KEYWORDS: Intact and reconstituted states, Soil-water retention characteristics, Initial state of soil, Drying- and wetting- paths, Swelling clays, Dewpoint Potentiometer
