Effect of Glass Industry Waste on the Physical, Mechanical, and Durability Properties of Slag-Based Geopolymer Composites Produced with a Ternary Alkali Activator System

This study, aimed at reducing the environmental impact of industrial waste from the steel and glass industries, investigates the effect of glass industry waste on the physical, mechanical and durability properties of slag-based geopolymer composites produced with a ternary alkali activator system. Silica powder, a waste product from the glass industry, was substituted for ground blastfurnace slag in specific proportions. The ternary alkali activator system used consists of 10M NaOH, Na₂SiO₃(aq) solution and sinter ash containing Na₂SO₄. Experimental tests were carried out on the produced geopolymer composites, including spread, water absorption, shrinkage, capillary water absorption, compressive strength and acid resistance. The substitution of 5% silica powder significantly improved the physical, mechanical and durability properties of the geopolymer composites. Silica powder increased the workability of the composites by 40-45% and reduced shrinkage, capillary water absorption and porosity while improving resistance to acidic media. These results represent a significant potential for the effective use of industrial waste in geopolymer materials, helping to minimise environmental impact and produce sustainable, economically efficient materials.