Alkali-activated slag-metakaolin pastes: strength, structural, and microstructural characterization

This study investigates the properties of alkali-activated slag-metakaolin pastes focusing on their strength, structural, and microstructural characteristics. The objective was to analyze the effects of different mass ratios of granulated blast furnace slag (GBFS) and metakaolin (MK), specifically the ratios of 100/0, 50/50, and 0/100, on the performance of the pastes. The methodology involved preparing pastes with varying proportions of GBFS and MK and examining their compressive strength through standardized testing protocols. Additionally, microstructural analyses were conducted using advanced characterization techniques. The results revealed significant variations in mechanical performance and structural properties depending on the GBFS/MK ratios. Notably, the 50/50 ratio demonstrated optimal strength characteristics due to the synergistic effects of both materials. The microstructural analysis indicated that the presence of MK enhanced the formation of binding phases, thus improving the overall durability and sustainability of the pastes. This research provides valuable insights into the use of alkali-activated materials in construction applications, suggesting their potential as a viable alternative to traditional cement-based systems.