SOME STUDIES ON THE SWELLING BEHAVIOUR OF EXPANSIVE SOILS

Abstract

The problems related to expansive soils is world-wide. The countries in which expansive soils are present in large areas are Argentina, Australia, Burma, Canada, India, Israel, Iran, Mexico, Morocco, South Africa, Spain, U.S.A. and Venezuela. In India, these expansive soils also known popularly as "Black Cotton Soils" cover a large area of approximately 810,000 square kilometers. The parent material from which the expansive soils derive their origin is the Deccan plateau. basic igneous rock, i.e.. Basalt of the In this study, the anisotropic swelling behaviour of bentonite and a black cotton soil which is brought from Akola in Maharashtra has been studied. Further the influence of compaction water content and compactive energy have also been studied. I.S. light and heavy compaction tests were conducted and samples were taken at optimum moisture content, dry. side and wet side of optimum moisture content. From the compacted soil, samples were taken at angles of 00, 45o, and 900 to the vertical, that is, the direction of compaction. The percent swelling and swelling pressures were measured by consolidometer method as per IS: 2720 (part XLI)-1977. These measured values are compared with some of the empirical equations available in, literature.