Development of sustainable concrete incorporating metakaolin and sintered fly ash aggregate.

The importance of using sintered fly ash aggregates (SFAs) as coarse aggregate and metakaolin (MK) as partial replacement of cement for generating sustainable concrete has been accessed in this research. For this, concrete mixes are designed by replacing 0%, 15%, 30%, and 45% natural coarse aggregates (NCAs) by SFA and incorporating 0%, 10%, 15%, and 20% MK in place ordinary Portland cement (OPC) along with a constant water‐binder ratio (0.42). Workability, compressive, split tensile and flexural strength, and nondestructive parameters and other characteristics (water absorption, volume of voids, and density) of designated mixes are evaluated by performing various experiments in the laboratory. The study demonstrates that significant degradation in concrete behavior has been observed with the use of 45% SFA and 20% MK. However, usage of 30% SFA in place of NCA and 10–15% MK as cement replacement is beneficial in achieving the desired target strength and fulfills other concrete requirements for practical use. [ABSTRACT FROM AUTHOR]