Abstract:
Unlike other failure modes like flexural failure, almost no warning occurs for structures at the
onset of failing in shear. Therefore, it is important to evaluate the accuracy of the determination
the shear capacity of reinforced concrete beams by different design standards. This study
evaluates the accuracy of some of the equations proposed by different codes of standard.
Moreover, in order to gain an understanding of how different parameters, such as concrete
strength, shear span-to-depth ratio and amount of longitudinal reinforcement affects the shear
resistance of concrete beams without transverse reinforcement.
For this purpose fifty-six reinforced rectangular concrete beams without transverse
reinforcement have been selected from different experimental studies by other researchers taking
into account longitudinal reinforcement, compressive strength of concrete and shear span to
depth ratio. The experiment result is used to evaluate the accuracy of the prediction of some
building codes, i.e., ACI 318-14, 2011,Eurocode 2, 2004, Zsutty, 1971, and Niwa et al. 1987. It is
shown that the shear strength predicted by Zsutty,1971 shows good agreement with the test
results having a better correlation coefficient of 0.712, and a mean ratio of 1.941 in
predicting the shear strength of the selected 56 test beams than EC2,2004, ACI 318 and Niwa
et al.1987 with correlation coefficient of 0.569, 0.5035 and 0.661 respectively, which predict
the shear strength conservatively.
The parametric study is carried out using the commercially available finite element package
ABAQUS 6.14. The parametric study has been restricted to concrete compressive strength (25,
35, 40 and 60), longitudinal steel reinforcement ratio (0.679, 0.905 and 1.13) and shear span to
depth ratio (1.5, 2 and 2.6). The result of finite element for analysis indicates that as concrete
compressive strength increase, the shear capacity of reinforced beam without transverse
reinforcement was increased. Also, by increasing the amount of longitudinal reinforcement to
some limit, the shear capacity of RC beam without transverse reinforcement was increased, and
in contrast, when the ratio of shear span to effective depth increase, the shear capacity of beam
decreased