Evaluation of steel fibers addition in fluid concrete subjected to tensile stress

Abstract

The development of new technologies for the production of concrete, over the time, have contributed to increase its compressive strength, improve workability and to ensure durability for structures executed with the same. Despite its many advantages and improvements achieved, the concrete when applied in situations which arise tensile stresses shows limitations related to its brittle behavior. An alternative to overcome this problem is to use dispersed fibers immersed in the concrete, thus creating a composite material with different characteristics from the original material. In order to collaborate in analysing the added fiber efficiency, this paper deals about the behavior of steel fibers reinforced fluid concrete when tensile stresses is applied, considering fiber aspect relation form and  volume fraction the influence  parameters. For this evaluation, we used cylindrical specimens, dimensions of 10 cm x 20 cm, considering 0.4% and 0.8%, related cement weight, to steel fibers addition and relation aspect form of 33, 50 and 80. Tensile tests by diametrical compression was done and it was possible to say that steel fiber reinforced fluid concrete is more efficient when tensile stress is applied with larger relation aspect form and greater volumetric fraction, it tends to be more efficient in response concrete subjected to tensile stress.