Combined effect of waste glass powder and recycled steel fibers on mechanical behavior of concrete

Several attempts upon inclusion of industrial waste materials such as fly ash, silica fume, GGBS, metakaolin and copper slag in concrete have already been experimented that exerted a significant impact on concrete with enhanced mechanical and improved durability properties. There were numerous authentic researches that reported the significance of steel fibers in strengthening the flexural property of concrete. The paper investigates the combined effect of waste glass powder (WGP) that has been utilized as a substitution for fine aggregate in varying percentages of 0%, 3%, 6%, 9%, 12% and 15% and further reinforcing it with recycled steel fibers (RSF), drawn from waste tires by volume of concrete. WGP was used as 0%, 3%, 6%, 9%, 12%, 15% by mass replacement of fine aggregate with four different volume fractions of recycled steel fiber (i.e., 0, 0.5, 1 and 1.5%), respectively. All proportions of concrete mixes were investigated to study the variations in compressive, flexural and split tensile strength with varied replacements levels of WGP along with various fractions of RSF for 7 and 28 days curing. A mix of 9% WGP exhibited the maximum compressive, flexural and split tensile strength. It was found that mechanical properties of concrete rose up to 9% replacement level of WGP and later declined. Also it was confirmed that increase in the amount of RSF further boosted the compressive and flexural behavior of concrete. Overall, an optimum concrete mix with 9% replacement of WGP, reinforced with 1% inclusion of RSF, reported the best performance compared to other mixes.