Performance enhancement of green concrete

Abstract

Several factors, such as energy-saving methodologies and techniques and improved use of materials, need to be considered for the development of sustainable construction materials. In the present work, the feasibility of using industrial inorganic polymeric residual wastes as a total (100%) replacement for traditionally used normal concrete materials was examined in the preparation of geopolymer concrete (GPC). In this study’s GPC, the cement was replaced totally by fly ash (class F) and ground granular blast furnace slag (GGBFS), the fine aggregates were replaced totally by bottom ash, the coarse aggregates were replaced totally by water-cured fly ash aggregates (WCFAs), which were prepared by using class C fly ash by adopting the pelletisation technique. The GPC mixes were cast with WCFAs at 0, 10, 20 and 30% replacement of fly ash (class F) by GGBFS with different molar ratios of sodium hydroxide (NaOH) solutions (8, 10, 12 M). The concrete was cured at ambient temperature only to minimise the water during water curing. The physical and mechanical properties of the GPC were studied by using the combination of all the mentioned materials. It was observed that the GPC mixes at 30% GGBFS with 12 M sodium hydroxide attained a maximum compressive strength of 38·94 MPa.