Comparative Analysis on Partial Replacement of Cement by Mixture of Nano-Silica, Metakaolin, Ground Granulated Blast Furnace Slag

Abstract

The manufacture of cement produces lot of pollution like about produce 7% of carbon dioxide emission, which has encouraged the use of supplementary cementitious materials to develop sustainable concrete. This study investigates the effect of partial replacement of cement with nano-silica (NS), metakaolin (MK) and GGBS. Cement was partially replaced by nano-silica with different dosages are 1%, 1.5%, and 2%, metakaolin fixed dosage 8%, and GGBS at 60% by weight of cement. A conventional concrete is also prepared to comparison. Concrete specimens were cast and tested to evaluate strength of concrete. The addition of nano-silica enhanced early-age strength due to its high pozzolanic reactivity and while metakaolin contributed to improved strength. GGBS significantly improved long-term strength and sustainability by reducing cement content and heat of hydration. From the use of mixture of nano-silica, metakaolin, and GGBS improves the overall performance of concrete, with the optimum nano-silica content observed at 2% replacement. This blended cement concrete demonstrates enhanced strength characteristics and offers an eco-friendly alternative to conventional concrete.