Influence of Slag, Silica Fume and Waste Tire Wire on High-Strength Characteristics of Geopolymer Concrete Cured Under Ambient and Oven Conditions

Higher strengths can be achieved using environmentally friendly geopolymer concrete (GPC). Granulated blast-furnace slag (GBFS) and silica fume (SF) were used together in high-strength GPC, and the GBFS + SF mixture was replaced with fly ash at total rates of 5, 10, and 15%. Recycled waste tire wires were added at rates of 1, 2, and 3% by weight. The samples were cured under ambient and oven conditions for 28 days and subsequently tested to characterize their compressive, flexural, and splitting tensile strengths. The test results indicated that adding waste tire wires significantly influenced the samples cured under ambient conditions, leading to a strength increment of up to 45 MPa-an improvement of approximately 50%. The oven-cured samples improved strength by approximately 21%, and the maximum compressive strength peaked at 65 MPa. This result can be used as a positive reference for high-strength concrete. The addition of 3% waste tire wire resulted in a flexural strength of 15 MPa in samples cured under ambient conditions and up to 23 MPa in those cured in an oven. The splitting tensile strength peaked at 16 MPa, which agrees with the bending strength. Scanning electron microscopy and energy-dispersive X-ray analysis were performed on these samples, and the results corroborated these findings, yielding robust supporting evidence for the obtained results.