Behaviour of silty sands stabilised with cement subjected to hard environmental conditions

Abstract

The present study evaluates the effect of three distinct amounts of fines, Portland cement and dry unit weights on the accumulated loss of mass (ALM), maximum shear modulus at small strains (G0) and tensile strength (qt) of stabilised sands subjected to wet-dry cycles. Tensile strength test results showed that addition of fines to a sand stabilised with cement increased its tensile strength, irrespective of the dry unit weight (γd) and cement amount present in the mixture. Increasing the amounts of fines of compacted cement-stabilised silty sand specimens subjected to wetting-drying cycles reduces ALM and increases G0 and qt of the mixtures. This may be due to the fact that specimens with larger amounts of fines have more contact points amongst particles, which provides better opportunities for the cement to develop more efficient bonds within the soil fabric, improving its mechanical performance. The increase in cement content and in γd of compacted cement-stabilized silty sand specimens reduced their ALM and increased G0 after each one of the twelve wet-dry cycles. The G0 and qt of cement-stabilized silty sand specimens with fines increases up to the sixth cycle, remaining practically constant after that, when these specimens are subjected to wetting-drying cycles.