Prof. D. N. Singh

SNEHA JAYANTH

M.Tech.
Indian Institute of Technology Bombay, Powai, India snehaj.0812@gmail.com

INFLUENCE OF DRYING- AND WETTING- CYCLES ON SWCC OF FINE-GRAINED SOILS

The Soil Water Characteristics Curve, SWCC, gets greatly influenced by the type of the fine-grained soil and initial conditions (viz., density, void ratio, water content, environmental conditions such as humidity and temperature). Apart from these parameters, the path that is followed for suction measurement (i.e., drying- or wetting- path) also influences the SWCC quite significantly. In order to quantify these influences, efforts were made to develop a methodology for establishing SWCCs by employing a dewpoint Potentiameter (WP4) and AquaSorp? Isotherm Generator, for three fine grained soils of completely different characteristics. Drying- and wetting-path SWCCs were established for single and multiple cycles, by varying the specimen thickness and maintaining the molding water content close to the liquid limit of the soil. These investigations highlight the possible uncertainties associated with establishment of the SWCCs and the benefits and limitations of these devices. Based on the study, recommendations have been made for proper and effective utilization of these devices as well. Further, in order to demonstrate the significance of capillarity on soil suction, which governs the SWCC ultimately, the Mercury Intrusion Porosimetry, MIP, has been employed and its utility for the said purpose has been demonstrated.