Avaliação da resistência ao cisalhamento direto em peças de concreto reforçadas com fibras de aço

Abstract

This work analyzes the mechanical behavior of concrete parts reinforced with steel fibers. Eighteen prismatic concrete parts were subjected to direct shear till break or, when this was not the case, the vertical displacemant of 2,5 mm was assumed as the limit variable. Additionally, prisms were tested with the aim to characterize the contribution of fiber in shear strength and increase control of the cracks in the concrete. Steel fibers used were rectilinear, with hook at the ends, to 60 mm in length, diameter of 0,75 mm and form factor equal to 80, and were added in the volumetric fraction of 0,5 and 1,0%; these percentages in relation to the total volume of concrete to their respective concreting. The results showed that the fibers contributed to the increase of the shear strength and controlled satisfactorily the opening of cracks in concrete parts. The results were compared with values obtained by other authors who used different steel fibers or even equal to this work, as reinforcement in concrete, having been observed that the experimental values reached the expected.