| Abstract: |
Cement production accounts for approximately 8% of global CO₂ emissions, making the construction sector a primary contributor to climate change. This study examines the potential of industrial waste materials fly ash (FA), ground granulated blast furnace slag (GGBS), and silica fume (SF) as supplementary cementitious materials (SCMs) for producing carbon-neutral concrete. The primary objectives are to quantify CO₂ reduction achievable through high-volume SCM substitution and to assess its influence on mechanical and durability properties. Five concrete mix designs were developed with varying proportions of FA, GGBS, and SF replacing ordinary Portland cement (OPC) up to 80%. Results demonstrated that a ternary blend (FA+GGBS+SF) reduced CO₂ emissions by up to 61% relative to OPC control concrete while achieving 28-day compressive strength of 44.8 MPa. Life cycle assessment (LCA) confirmed that 65% FA substitution reduced energy requirement by 59% and lifecycle cost by 34%. Findings validate the hypothesis that strategic incorporation of industrial waste SCMs can achieve near-carbon-neutral concrete production without compromising structural performance, offering a viable pathway toward the Global Cement and Concrete Association's 2050 net-zero target. |
