محمد مقصودی

By considering the adverse environmental impacts of the cement manufacturing process, there have been many efforts for cement replacement by supplementary cementitious materials (SCMs), which can enhance the produced concrete performance while reducing cement consumption. This study evaluated the effects of various proportions of silica fume (SF), waste glass powder (WGP), and ground granulated blast furnace slag (GGBFS) on the mechanical and durability properties of concrete. The properties evaluated in this study include compressive, tensile, and flexural strength, magnesium sulfate and sulfuric acid attack, surface resistivity, rapid chloride penetrability test (RCPT), water absorption, depth of penetration of water, and microstructure analysis by scanning electron microscopy (SEM). The results of compressive, tensile, and flexural strength, chloride ion penetrability, and water absorption tests showed that adding 5% of SF to mixtures containing 10% WGP or 10% GGBFS improved concrete performance significantly due to packing density and synergistic effect; however, adding 5% of SF to concrete mixtures decreased the resistance against the magnesium sulfate and sulfuric acid attack. The binary mixture of 15% of WGP showed appropriate performance against the magnesium sulfate and sulfuric acid attack, which may be due to the sacrificial nature of WGP. In addition, the binary mixtures of 15% of WGP and 15% of GGBFS reduced the depth of penetration of water by 45%. Microstructure analysis by SEM showed that the presence of SF, along with WGP and GGBFS, improves the packing density. Finally, adding 5% of SF is suggested to improve the properties of concrete mixtures containing WGP and GGBFS.