STEEL FIBER REINFORCED SELF- COMPACTING CONCRETE INCORPORATING CLASS F FLY ASH

Self-compacting concrete (SCC) offers several economic and technical benefits; the use of steel fibers extends its possibilities. Steel fibers acts as a bridge to retard their cracks propagation, and improve several characteristics and properties of the concrete. Fibers are known to significantly affect the workability of concrete. Therefore, an investigation was performed to compare the properties of plain normal compacting concrete (NCC) and SCC with steel fiber. Ten SCC mixtures and one NCC were investigated in this study. The content of the cementitious materials was maintained constant (600 kg/m 3 ), while the water/cementitious material ratio is kept constant 0.31. The self-compacting mixtures had a cement replacement of 35% by weight of Class F fly ash. The variables in this study were aspect ratio (0, 15, 25 and 35) and percentage of volume fraction (0, 0.5, 1.0 and 1.5) of steel fibers. Slump flow time and diameter, J-Ring, V-funnel, and L-Box were performed to assess the fresh properties of the concrete. Compressive strength, splitting tensile strength and flexural strength of the concrete were determined for the hardened properties. A marginal improvement in the ultimate strength was observed. The addition of fiber enhanced the ductility significantly. The optimum volume fraction (V) and aspect ratio (A) of fiber for better performance in terms of strength was found to be 1.0 percent and 25. The results indicated that high-volume of fly ash can be used to produce Steel fiber reinforced selfcompacting concrete, even though there is some increase in the concrete strength because of the use of steel fiber and high-volume of fly ash.