Impact of drying-wetting on strength of a cement-treated lightweight fill

Abstract

Nine series of samples were prepared by mixing waste foundry sand (WFS), fly ash (FA), expanded polystyrene (EPS) beads, Portland cement and water in proportions, which leads to a cement-treated lightweight fill. The samples were exposed to designated drying-wetting (D-W) cycles, after which, tests of unit weight and unconfined compressive (UC) strength were carried out to observe the structural impairment possibly taken place to the samples. Test results indicate that the unit weight of the samples was 20-40% less than that of general fill materials. The materials presents an acceptable mechanical behavior and offers promise as a lightweight soil-cement mixture after an exposure to up to 8 D-W cycles. Additions of proper cement and FA contents lead to an enhanced D-W resistance. Albeit EPS addition prompts the light weight of the geomaterial, its addition, if above 1%, leads to strength loss, and should be controlled within a reasonable range.