Waste Glass as Partial Cement Replacement in Sustainable Concrete: Mechanical and Fresh Properties Review

The significant anthropogenic carbon dioxide (CO2) emissions from cement production and the disposal of the majority of post-consumer waste glass into landfill sites have increased environmental pollution. In order to reduce the environmental impact, ground glass pozzolan (GGP) as a partial cement replacement has drawn interest from the concrete industry. This review examines the potential of GGP as a supplementary cementitious material (SCM), exploring the chemical composition of pozzolans, the different types of glass used for GGP, and the impact of glass color on pozzolanic reactivity. In addition, this study gathers the most recent research articles on the fresh and mechanical properties of concrete incorporating GGP. Key findings show that the incorporation of GGP in concrete improves the modulus of elasticity and the compressive, tensile, flexural, and punching strengths due to the pozzolanic reactions. The results indicate that GGP, made from waste glass, has pozzolanic properties that form additional strength-enhancing calcium silicate hydrate (C-S-H) gel and densify the concrete matrix. Additionally, the life cycle assessments of GGP-incorporated concrete demonstrate reductions in energy consumption and CO2 emissions compared to conventional concrete, supporting a circular economy and sustainable construction practices.