Effect of steel slag and ceramic residues on the physical and mechanical properties of concrete

Abstract

Cement is a critical component in concrete, but it significantly impacts the environment from extraction to disposal, depleting resources and generating pollution. To address this issue, the use of steel slag (SS) and ceramic waste powder (CWP) was investigated as partial replacements for cement at 8%, 10%, 12%, and 15% by weight. Various mixtures were evaluated, including a control mix with a water-to-cement (w/c) ratio of 0.52, mixtures containing SS, and an optimal blend of SS with different proportions of CWP. Physical and mechanical properties were assessed through slump tests, temperature measurements, air content, and density evaluations. Compressive strength, flexural strength, tensile strength, and modulus of elasticity were also analyzed at 7, 14, and 28 days using standardized cylindrical and prismatic specimens. The results indicated a reduction in slump and temperature of the concrete by up to 45.87% and 9.10%, respectively, with a slight increase in density and air content when incorporating 10% SS and 15% CWP. In terms of mechanical properties, the optimal substitution of 10% SS improved compressive strength by 7.39%, modulus of elasticity by 13.06%, flexural strength by 8.22%, and tensile strength by 14.10% compared to the control mix. The hybrid mix of SS and CWP (10%:10%) showed significant enhancements: compressive strength increased by 17.12%, flexural strength by 19.25%, tensile strength by 26.28%, and modulus of elasticity by 21.21%. It was concluded that substituting 10% SS and 10% CWP by weight of cement enhances the mechanical properties of concrete, promoting efficiency and sustainability in environmentally friendly construction. This hybrid concrete can be effectively used in pavements, sports floors, sidewalks, and curbs.