PSI - Issue 70

Yankesh et al. / Procedia Structural Integrity 70 (2025) 311–318

313

NaOH (8M), aggregates (77%), and alkaline liquid-to-fly ash ratio of 0.4 achieved 3.87 & 17.67 MPa strength (ambient) and 28.31 & 33.22 MPa strength (heat-cured) at 7 & 28 days respectively (Vijai et al., 2010). A mix ratio (1:1.5:3.3) with solution-to-fly ash ratio (0.35) and 10M NaOH – sodium silicate (2.5:1) yielded 53.33 MPa strength under steam curing at 60°C (Abdul Aleem et al., 2012). With a 0.4 alkali to precursor ratio and 0.5 water to binder ratio gives ffavourable properties, including good workability, competitive compressive strength, and reasonable density. (Oti J et al., 2024). GPC has emerged as a strong alternative in recent years, offering up to 80% less carbon dioxide emissions compared to conventional Portland cement.

Fig. 2. (a) Performance Features of GPC vs Conventional Concrete; (b) SEM analysis of GGBS at 8µm (Ganesh A et al., 2020)

It also helps reduce costs and the need for raw materials, making it a more sustainable choice for modern construction. (Almutairi A et al., 2021). The price range may depend on the quantity and quality of the production on an average GPC turns out much more affordable up to 40% cheaper than traditional concrete. (Verma M et al., 2022). Geopolymer structure first introduced by Davidovits. At the core of this structure is a network made from silicon and aluminium tetrahedra (SiO₄ and AlO₄), linked together by shared oxygen atoms. Because aluminium carries a negative charge, the structure needs positive ions like sodium, potassium, or calcium to stay balanced and stable resulting in a strong and durable geopolymer material as shown in the equation 1 and in fig. 2(c) (Askarian M et al., 2021). CaO. 0.4 SiO 2 0.4Al 2 O 3 . 0.1MgO + Na 2 SiO 3 + H 2 O → Geo-Polymer (1)

Fig. 2. (c) Geo-polymerization reaction (A skarian M et al., 2021 )

2. Experimental work 2.1. Materials

Ground Granulated Blast Furnace Slag (GGBS) used in this study, procured from JSW Cement Ltd. It is an industrial by-product, produced from the iron-making process, when iron ore, coke, and limestone are processed in a blast furnace. The resulting slag is rapidly cooled by sprinkling water, dried, and ground into fine powder. 10- and 20 mm Coarse Aggregates (CA) and river sand as Fine Aggregate (FA) conforming to IS standards were used, arranged