INFLUENCE OF HOOKED-END STEEL FIBERS ON FLEXURAL BEHAVIOR OF STEEL FIBER REINFORCED SELF-COMPACTING CONCRETE (SFRSCC)

Abstract

The weaknesses of the concrete material are weak to the tensile strength and brittle. The solution to overcome this weakness is by adding fibers like steel fiber. The use of steel fibers has constraints in workability. It was developed to become self-compacting concrete (SCC) to facilitate work in the field. SCC, which uses additional steel fibers, is known as steel fibers reinforced self-compacting concrete (SFRSCC). In this study, the use of steel fibers in the SFRSCC was examined where the steel fiber used was a hooked-end type. Hooked-end steel fibers have been developed into several forms, namely 3D, 4D, and 5D. This study aimed to analyze the effect of hooked-end steel fibers consisting of 3D, 4D, and 5D types on the workability, modulus of elasticity, and flexural behavior of SFRSCC. The experimental method in this study refers to the EFNARC standard for the workability test, ASTM C-469 for the modulus of elasticity test, and ASTM C-1609 for the flexural strength test. Workability tests such as slump flow, T-500, V-funnel, and L-box decreased with the addition of steel fiber. The best workability is found in 3D type steel fiber with a fraction of 0.5, with details of slump flow = 677 mm, T-500 = 4.36 seconds, V-funnel = 9.35 seconds, and L-box = 0.92. In the various shapes of hooked-end 3D, 4D, and 5D, the type that provides increased flexural strength and maximum energy absorption capacity of SFRSCC is type 5D. Energy absorption in steel fiber type 3D = 147.23 Joules, type 4D = 166.16 Joules, and type 5D = 178.03 Joules. The hooked-end shape greatly absorbs energy when the beam is subjected to bending forces. Type 5D steel fiber is the most common form of hooked-end. The more hooked-end forms, the tensile strength of steel fiber increases. The increase in the tensile strength of steel fibers resulted in the SFRSCC's flexural strength increasing.