Enhancement Characteristics of Geo-Polymer Concrete Based on Fly Ash Incorporating Glass Waste and Polypropylene Fiber

Abstract

Portland cement production accounts for 8–10% of global anthropogenic CO₂ emissions, creating an urgent need for sustainable alternatives. Geo-polymer concrete (GPC) based on fly ash offers a compelling low-carbon binder; however, systematic evaluation of ternary systems incorporating fly ash, waste glass, and polypropylene (PP) fibers remains limited in the literature. This systematic review examined 110 peer-reviewed studies published between 2015 and 2025, retrieved from Scopus and Web of Science using structured keyword searches. Studies were included if they addressed fly ash-based GPC incorporating waste glass, PP fibers, or both, and reported quantitative mechanical or durability data. Fly ash-based GPC with 10–25% waste glass replacement achieves compressive strengths of 35–75 MPa. Adding PP fibers at 0.5–1.0% by volume improves flexural capacity by 15–40% and increases fracture toughness by 150–300%. Durability testing confirms superior resistance to chloride penetration (RCPT < 1000 coulombs), sulfate attack, and freeze–thaw cycling relative to conventional Portland cement concrete. Life-cycle assessment reports 60–80% reduction in CO₂ emissions and utilization of 400–550 kg of industrial by-products per cubic meter. The ternary GPC system delivers synergistic mechanical and durability benefits; however, standardization gaps, workability limitations, and the absence of long-term field validation must be resolved before wide-scale structural adoption.