Experimental Investigation of Shear behaviour of RC deep beams by Replacing regular concrete with HPFRCC

Nowadays the use of special and efficient concrete in concrete structures is increasingly spreading due to its unique characteristics. To overcome the issues is to reinforce the concrete by fibers which lead to the formation of multiple micro-cracks that is the main characteristic for providing the tensile ductility of HPFRCC materials. The influence of this material on bending behavior has been studied by many researchers. Thus, its influence on the shear behavior of deep beams is evaluated in this article. For this purpose, the empirical response of five beams including the conventional HPFRCC reinforced deep beams, under concentrated load, in the middle of the span with the shear span to depth ratio of 0.75 is evaluated. Deep beams of the first group with various fiber percentages of 0, 1 and 2, and, deep beams of the second group with steel fibers of 0 and 2 percent were constructed. The specimens of the first group did not have the web shear reinforcement while specimens of the second group had. After testing the specimens, it was observed that as the percentage of steel fibers increases, the bearing capacity and ductility of the specimens increases as well. Increasing the fiber percentage and adding shear reinforcement increases the shear deformation coefficient. On the other hand, F2 specimens in the second group, which have a shear reinforcement, have a residual coefficient of 9% higher than the same one in the first group (without shear reinforcement).