The behavior of R.C deep beams is predicted using a proposed layered isoparametric finite element model. most of the properties of concrete in compression and tension domains were considered in the model. The model was used to study the behavior of deep beams with and without openings taking into consideration progressive cracking of concrete, effect of shear-span to depth ratio, opening's size, location and skew (anisotropic) reinforcement around openings. The model was verified by comparing predicted behavior with experimental and theoretical results in the literature. It was found that the increase in shear-span to depth ratio lead to a general enhancement of the beam ductility, however, there was a reduction of its stiffness. In addition, the opening location and size had a great effect on the behavior of the beams. The provision of additional reinforcement around openings, especially, anisotropic reinforcement perpendicular to major crack direction, had a significant effect on the behavior of reinforced concrete deep beams, namely, increasing their ultimate strength. Such additional reinforcement also affects the cracking propagation behavior throughout loading process. |
