Development of sustainable slag-based alkali-activated concrete incorporating fly ash at ambient curing conditions

To accomplish environmental sustainability and reduce carbon emission, the construction industry needs to adopt waste industrial by-products as construction materials. To resolve this issue, this study investigated the strength and durability performance of alkali-activated concrete (AAC) using industrial waste products such as ground granulated blast furnace slag (GGBS) and fly ash (FA). In AAC, GGBS was the major precursor and partially substituted with FA at 0 to 30% and the AAC mixes were prepared for 10 M and 12 M. Ambient curing is adopted here to make it convenient for in situ applications. The factors under investigation include setting time, slump, compressive strength and durability properties. The outcome of the test results shows that the setting time and slump increase with an increase in FA content in AAC. The water absorption, apparent porosity, permeable void and sorptivity values increase with an increase in FA concentration. In contrast, increasing the molar ratio from 10 to 12 M improves the durability of AAC mix. The acid resistance of GGBS-based AAC improves by using a higher amount of FA. Also, an increased molar ratio led to higher resistance against carbonation, chloride ion penetration and acid attack. In addition, the scanning electron microscope is utilized to investigate the microstructural characteristics. The outcome of this study could potentially contribute to improving the durability of AAC and exploration to protect measures of AAC in aggressive environments.