Flexural performance of steel fiber reinforced concrete beam

Abstract

Steel fibers are generally used as resistance of cracking and strengthening of concrete. According to previous research, it has been found that steel fiber (SF) reinforced concrete beam had higher flexural strength compared to conventional reinforced concrete beam. In this research, flexural performances of steel fiber reinforced concrete beams were studied for concrete grade 35. Optimum fiber content was found to be 1% and this was determined using compressive strength test with different SF dosages (0%, 1% and 2%). Mechanical properties of steel fiber reinforced concrete were determined through compressive strength, tensile strength and flexural strength. The result indicates that there is a slight increment in compressive strength and splitting tensile strength of SFRC of about 15% and 30%, respectively compared to control sample. The flexural strength shows a significant increase of more than 100% at 28 days compared with the control sample. The flexural behavior of steel fiber reinforced concrete beams at 28 days were studied under four points loading and the results were compared with conventional reinforced concrete beam. Beam 1 and Beam 3 failed at almost the same ultimate load. This shows that reinforcing the tension zone only has the same effect to that of reinforcing in both tension and compression zones. Beam 2 with steel fiber has slightly higher ultimate load, although the area of reinforcement was reduced. The use of steel fiber in concrete shows a significant improvement on the ductility and stiffness characteristics of the beams than the control beam.