Effect of Fibers on Bond Performance of Lightweight Reinforced Concrete

Integrity of a reinforced concrete member, or structure composed of such members cannot be ensured if there is inadequate bond between reinforcement and concrete around it. In current experimental work, effect on bond performance of lightweight concrete is discussed after addition of steel fibers. For the purpose, modified Pull-out specimens were tested at 28 days. Hooked end steel fibers having length of 35 mm and 0.5 mm in diameter, developing aspect ratio of 70 were used. Fiber contents of 0, 20 and 40 kg/m(3) were added to the lightweight concrete mixes. Besides bond behavior, results of fresh and hardened properties are also presented. Results indicate higher tensile strengths and pull-out loads for higher fiber contents. The fresh concrete density and compressive strength of mixes reduced, whereas air-content values increased with higher fiber content.