Effects of Shape of Steel Fiber on Mechanical Properties of High-Performance Concrete Containing Bottom Ash as Cement and Fine Aggregate Replacements

This article presented the effects of shape of steel fiber on mechanical properties of highperformance concrete containing 60% ground coal bottom ash (GBA) blended with10% fly ash (FA) as a cement replacement. In addition, coarse bottom ash was also used to replace fine aggregate at a rate of 30% by volume. All shapes of steel fibers i.e.,straight, hook-end, and crimped having an aspect ratio (l/d) of 65 were used. The volume of steel fiber was controlled as constant of 1.0% in all concrete mixtures.The results revealed that the use of steel fibers caused a decreasing in workabilityof concrete in terms of slump flow and T50. The use of 1.0% hooked-end fiber gave the highest compressive strength and flexural strength of concrete, with values equal to 874 and 157.2 kg/cm2 respectively, at 28 days. Additionally, Shapes of steel fiber did not affect the modulus of elasticity of concrete. When the steel fiber was used at 1.0% by volume.