Numerical investigation of the effect of support conditions on beam shear behaviour in full scale reinforced concrete beams

In studies on beams in the literature, the beam elements are designed and tested as simply supported. Therefore, in this study, the behaviour of reinforced concrete (RC) beams under fixed support conditions was numerically investigated using ANSYS finite element software. The variables used in the study are the shear span/effective depth ratio (a/d) and stirrup spacing of the analysed specimens. In this study, 16 RC beams on a 1/1 scale were analysed in 4-point bending protocol. The a/d ratios were assumed to be 1.0, 2.0, and 3.0, in the test members produced. In addition, as another variable, the lateral reinforcement amount was designed and analysed at f8/75, f8/150 and f8/300 mm spacings without stirrups. Load-displacement and stiffness graphs are drawn based on the numerical results. The numerical results were interpreted and compared based on the graphs drawn for each analysis, stress distribution, and damage occurrence in the experiments. The results indicated that the a/d ratio and number of stirrups had strong effects on the behaviour of the fixed supported beams. The results of the beam analyses obtained using ANSYS finite element software were consistent with the experimental results.