Cyclic swell–shrink behaviour of an expansive soil treated with a sulfonated oil

The effects of a sulfonated oil (SO) stabiliser on the swell–shrink properties an expansive soil were investigated through cyclic wetting–drying tests. action led to reconstruction microstructure by inducing clay particle aggregation. Accordingly, greater number applied cycles, lower potential up fourth cycle, beyond which swelling and shrinkage strains attained elastic equilibrium. At any given tendency for reduction was in favour SO concentration 0·75%, excess molecules self-associated form aggregates, thereby acting as ‘lubricant’ rather than clay-stabilising agent. As result treatment, accumulated axial strain progressively transitioned towards desirable, ‘neutral’ state, with 0·75% exhibiting highest resistance against wetting–drying. For concentration, equalised void ratio–moisture content curves wetting drying followed same S-shaped path, further corroborating that processes, achieving equilibrium, become reversible. liquid limits indicated progressive transition aggregated fabric, identified optimum concentration.