Influence of steel fibers extracted from waste tires on shear behavior of reinforced concrete beams

摘要

The accumulation of worn-out tires creates health and fire hazards, and researchers are busy to incorporate waste tire rubber in concrete instead of burning or dumping. After shredding of waste tires, steel beads were separated by magnetic separator. The potential utilization of wasted steel fibers in concrete was investigated in this experimental work; fresh and hardened properties of fiber-reinforced concrete (RC) were evaluated and compared with the conventional concrete. Shear behavior was investigated by conducting a four-point bending test on RC beams. Five types of RC beams were cast; two control specimens were cast, with and without stirrups, by using conventional concrete. Three types of beams were cast by using 0.40, 0.65, and 1.00% fibers by volume. Workability of fiber RC was lower than the conventional concrete. Linear increase in failure load was observed with an increase in the dosage of fibers, and a 64.3% increase in failure load was observed after 1% addition as compared to control specimen. Mid-span deflection, crack initiation load, and ultimate shear load were also increased with the addition of fibers. Crack spacing was reduced by 64.2% of specimen, with 1% dosage of fibers as compared to a control specimen without any stirrups, and a reduction in crack width was also observed with the addition of fibers.