Abstract
This article studies the behavior of concrete beams reinforced with metal fibers (chips) randomly arranged in concrete, to improve ductility and bending stiffness and limit crack openings. These fibers come from machining waste from steel parts. The fibers are characterized for mechanical resistance and tearing. Three series of tests were carried out for languor respectively L = 4 cm, L = 5 cm and L = 6 cm. Bending tests (three-point bending) are carried out on prismatic specimens of dimensions [10x20x120] cm3. Compression tests are carried out on cylinders with a diameter of Ø16 cm and a height of H32 cm in order to determine the mechanical properties of the concrete used. The composition of the concrete is determined by the experimental method known as “Dreux-Gorisse”. Two fiber contents are retained for this study (W= 0.6% and W= 0.8%) and a BT control concrete (W=0%) with W: fiber contents in the concrete, of the same composition as the matrix is developed for serve as a reference. The confrontation and comparison of the different results obtained show that the fibers with languor L=6 cm confer significant ductility to the material after cracking of the concrete, better than the other languor’s (L= 4 cm and 5 cm) with numbers of undulations (spirals) n=3.5and 6. Also, the fibers used limit bending cracks and improve strength and rigidity.