Exploring the Use of Metakaolin and Portland Pozzolana Cement for Concrete Sustainability

A current challenge for the concrete industry is to add admixtures to produce concrete with improved strength. With this view, the present study explores compressive strength (fck) and flexural strength (fcr) for M40 grade of concrete with partial replacement Portland Pozzolana Cement (PPC) with metakaolin (Mk) in the range of 4% to 24 % by the weight of cement by adding ViscoFlux-2230+ as a superplasticizer to make the concrete workable. It was observed that up to 16% addition of metakaolin increased compressive and flexural strength by 27% and 15.78% respectively compared to ordinary concrete at 28 days. Similarly, for 7 days compressive and flexural strength was increased nearly by 20% and 13% respectively and for 90 days, it was observed to be nearly 15% and 16% respectively. A relationship between the compressive strength (fck) and flexural strength (fcr) of Mk concrete is developed. The early age compressive strength development was greater practically in all Mk concrete. Indirectly increasing the rate of metakaolin can lower the regularized CO₂ emission and resource consumption. From the results, concrete may be recognized as sustainable concrete.