Reusing granite waste in eco-friendly foamed concrete as aggregate

Abstract

The consumption of wastes from natural stone processing factories not only could prevent from degression of natural resources, but also preserve the environment to attain sustainable development. In this study, the feasibility of reusing granite waste produced by natural stone processing factories in production of foamed concrete was investigated. Seven foamed concrete mixtures with the density of 1400–2000 kg/m3 were designed, and it was made once with fine sand and once with granite waste. Compressive strength, flexural strength, water absorption, thermal conductivity and microstructure tests were done on specimens. Additionally, the life cycle assessment (LCA) of specimens was also evaluated. The results indicated that the microstructure of the foamed concrete using granite waste (FCGW) was similar to the foamed concrete using fine sand (FCS). Compressive and flexural strength of FCGW were 8% and 10% higher than the res42ults for FCS respectively. The cement paste of both specimens was similar, however due to the high water absorption of the granite waste, the maximum water absorption of FCGW was 17% more than FCS. Moreover, results revealed that replacement of granite waste had no influence on thermal conductivity of the specimens. The results of LCA showed that using granite waste instead of fine sand could lead to improve abiotic depletion (ADP), global warming (GWP), acidification (AP), eutrophication (EP) and photochemical oxidization (OP) by 16.4, 32.4, 13.3, 58.2 and 20.7%, respectively.