Hydro-mechanical properties of compacted sand-bentonite in a semi-and climate

Abstract

This article presents the preliminary findings of an experimental study conducted on uniform sand-bentonite mixtures, focussing on the investigation and prediction of the volume change and hydraulic properties of artificially prepared mixtures of natural bentonite (Na-smectite) and poorly graded fine sand. Compacted specimens of sand-bentonite mixtures with additions of 33%, 50% and 75% sand were tested to demonstrate the change in physical and mechanical properties as compared to the compacted bentonite with no sand, therefore obtaining the most feasible combination for achieving the required properties. Based on the experimental findings of swell-shrink behaviour, saturated hydraulic conductivity and soil-water characteristic behaviour, sand-bentonite mixtures with 75% sand proved to be quite effective in fulfilling the requirements for barriers in a semi-arid climate.