Optimization of ternary concrete made using slag and fly ash in ultra-fine form using desirability function approach

Abstract

In the study that is being given, ultra-fine fly ash and ultra-fine slag, are used to create ternary concrete, and its mechanical and durability qualities are examined. Fly ash and slag have been used in concrete for many years, but the usage of their finer forms has only lately been studied. Fly ash is utilised as the major replacement, and to create ternary concrete, Ultra Fine Slag (UFS) or Ultra Fine Fly Ash (UFFA) are combined with Fly Ash (FA). Ordinary Portland Cement (OPC) serves as the primary binding substance and is substituted with 20% and 30% FA by weight. To create four ternary combinations, 15% of UFFA/UFS is added to replace OPC. Investigations were conducted on the mixtures' compressive strength, tensile strength, volume of permeable voids, water permeability, chloride migration coefficients, and sorptivity. According to the results, adding UFFA or UFS to concrete may improve its technical qualities. The optimum alternative combination is found using the optimization technique known as the Desirability Function Approach (DFA). Chloride migration, water permeability, and sorptivity of a mix consisting of 55% OPC, 30% FA, and 15% UFS, respectively, significantly improved by 94%, 92%, and 61%. Comparing the compressive strength and volume of permeable voids of the same combination to OPC concrete alone, similar improvements of 36% and 29% were found. According to the experimental findings, UFS should be chosen over UFFA in ternary concrete compositions for the mechanical and durability attributes that were under investigation.