Evaluating the Performance of Low Carbon GGBS & Metakaolin Geopolymer (Cement Free) Concrete: Impact of Binder Composition, Curing Methods, and Activator Ratios on Compressive Strength

Concrete production’s reliance on traditional Portland cement is a significant contributor to global construction and development. Concrete production’s reliance on traditional Portland cement is a significant contributor up to 10% global CO2 emissions, prompting a need for sustainable alternatives. This study explores the use of geopolymer binders, composed of industrial and agricultural by-products ground granulated blast furnace slag (GGBS) and metakaolin (MK), as a low-carbon alternative to conventional cement. An experimental investigation has been conducted to assess the workability and compressive strength of various cement free concrete mixes, tested at intervals of 5, 7, 28, and 91 days. The study also examined the impact of different curing methods (air and water curing) and activator-to-binder (a/b) ratios on the concrete’s mechanical properties. The findings revealed that both the binder composition and curing method significantly influence the compressive strength, with certain mixes demonstrating superior long-term performance, particularly those with optimized a/b ratios and higher GGBS content. These insights underscore the potential of geopolymer binders as a sustainable alternative to Portland cement, offering a viable path to reducing the carbon footprint of concrete production while maintaining structural integrity.