The investigation on shear behavior of reinforced concrete beams without shear reinforcement

The shear behavior of reinforced concrete elements is one of the most recent research topics in structural engineering. There is not a consensus how the mechanisms of cracking and strength developed, especially in reinforced concrete beams without shear reinforcement subjected to shear force. In this study, four point bending tests were carried out on fifteen reinforced concrete beams with four different shear span/effective depth (a/d=2.0, 2.51, 3.13, 4.0) ratios and four different concrete compressive strength. The crack developments of the beams during the experiment were followed in detail and also load-displacement graphics were obtained. The maximum shear force obtained for each sample from the experiments was compared with the results calculated using the three standards available in the literature and the equations proposed by some researchers. As a result of this experimental study; it is observed that the ratio (a/d) is one of the most important variables affecting the shear behavior of reinforced concrete beams under shear force. It is concluded that the relationship between concrete compressive strength and shear strength and fracture load is more complicated than expected and therefore more studies are needed to determine the effect of concrete compressive strength on shear behavior of reinforced concrete beams in a more rational way.