Swelling of Natural Soil Subjected to Acidic and Alkaline Contamination

This paper aims at establishing the influence of acidic and alkalinepore fluids on the swell behaviour of an expansive soil. Aseries of laboratory one dimensional free swell tests were performedto study the behaviour of soil in acidic and alkaline environment.Three different concentrations of sodium hydroxide andsulphuric acid solutions were used as pore fluids to understandthe influence of variable concentrations on the swell behaviourof soil. Results showed that, the swelling of soil that interactedwith sodium hydroxide solution initially increased at lower concentrationand then decreased with increase in concentration.In contrast, the swelling initially decreased at lower concentrationof sulphuric acid and then increased with increase inconcentration of solution. The complexity in the swell behaviourof contaminated soil was assessed by thoroughly investigatingthe mineralogy and microstructure alterations by carrying outX-ray diffraction analysis, Scanning electron microscopy andEnergy dispersive analysis of X-ray at the end of interaction.