Assessing the suitability of green concrete using waste glass as partial replacement for cement

Abstract

Green construction reduces the impact of the built environment on the natural environment and human health. The study of partial replacement of cement with waste glass powder and fire resistivity of concrete was investigated in two stages using quantitative approach, the first stage involved collection of waste glass samples, crushing and milling of the glass samples into powder less than 75μm, casting of concrete cubes at ratio 1:2:4 for concrete grade M15 (according to IS 456:2000) using 0%, 10%, 20%, 30%, 50% and 60% replacement of cement with waste glass powder. Compressive strength tests were carried out on the concrete cubes after curing ages (days) of 7, 14, 28, and 35.A total of 72 cubes were tested. The second stage involved testing for the strength of the concrete with 0% and 10% waste glass powder content obtained from the first stage as the optimum percentage replacement after heating to a temperature of 600℃ for 5 hours in a furnace. Result showed with 0% cement replacement with waste glass powder being the control, had the highest strength of all the samples, 10% had the second highest strength which exhibited a normal increased strength behaviour with increase in curing ages unlike all other percentage replacements making 10% replacement of cement with waste glass powder milled to a particle size of 75μmto be satisfactory. Fire resistivity at 5 hours gave 50% reduction in strength and the concrete was non-flammable. Use of waste glass could reduce cement content in concrete, suitable for green construction.

Keywords: Concrete, Compressive strength, fire resistivity, environment