Incorporating Sodium Silicate into Slag-based Geopolymer Concrete: A Comparative Study..

Portland cement production poses significant environmental challenges, rendering it unsustainable in the long term. Its manufacture entails considerable ecological concerns, thereby necessitating the adoption of sustainable development practices due to the finite nature of Earth's natural resources. In response, geopolymer concrete has emerged in the literature as a viable eco-efficient substitute for traditional concrete, offering potential advancements in reducing the environmental impact of construction materials. This study was aimed at exploring the comparison between geopolymer concrete mixture to explore the influence of sodium silicate inclusion in mix on the compressive strength. Two mixture trails GPC1 (without sodium silicate) & GPC2 (with sodium silicate) are tested. The results cleared that the average strength of GPC2 mix increased by 75% and 56% after 7 days and 28 days, compared to GPC1 mix. Sodium silicate serves as an essential component in enhancing the performance of slag-based geopolymer concrete that improved the geopolymerization process by supplying additional soluble silica, which promotes the formation of strong aluminosilicate gel networks. This leads to a denser microstructure, reduced porosity, and enhanced bonding between particles. As a result, concrete mixtures containing sodium silicate demonstrate higher compressive strength, particularly at early ages.