| Summary: | Shear failure in beams are caused by diagonal cracks near the support. Any form
of effectively anchored reinforcement that intersects these cracks will be able to resist the
shear stress to a certain extent. This project presents the results of an experimental
investigation on six reinforced concrete beams in which their structural behaviour in
shear were studied. All the beams were cast with the same grade of concrete, and
provided with identical amount of main reinforcement. In order to investigate the
contribution of the additional horizontal and independent bent-up bars to the shear
carrying capacity of the beam, two specimens each were provided with horizontal
longitudinal bars and bent-up bars in the high shear region. Two different quantities of
additional bars in each of these cases were adopted. The fifth specimen was provided
with sufficient amount of shear reinforcement in terms of vertical links, while the other
one was cast without any shear reinforcement to serve as control specimens. The
performances of the beams in resisting shear in the form of deflection, cracking, strain in
the shear reinforcement and ultimate load were investigated. The results show that the
shear capacities of the beams with additional horizontal and independent bent-up bars
larger than 1.2% of their cross-sectional area are higher than that of the conventionally
designed beam with vertical links. It may therefore be suggested that these types of shear
reinforcement be used to ease the congestion of links near the supports.
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