Experimental Study on Compressive Strength of Concrete by Partial Replacement of Waste Foundry Sand

Metal foundries use large amount of sand as a part of metal casting process. Foundries recycle and reuse the sand. The sand which can no longer be reused, it is removed from the foundry and it is termed as foundry sand. Annually around 6-10 million tons of foundry sand is produced. Foundry sand has many beneficial applications in other industries. It mainly consists of silica sand, coated with a thin film of burnt carbon, residual binders etc. It can be used in concrete to improve its strength and other durability factors. It is used as a partial replacement of cement or fine aggregates and total replacement of fine aggregate and as supplementary addition to achieve different properties of concrete. This paper presents the experimental investigation on the effect of foundry sand as fine aggregate replacement on the compressive strength, porosity, sulfate attack and XRD of cement mortar having mix proportions of 1:3. Fine aggregates were replaced with three percentages of foundry sand and the replacements were 5, 10, and 15% by the weight of fine aggregate. Tests were performed for all the replacement levels of foundry sand at different curing periods (7 days, 14 days & 28 days).