Shear strength of RC beams without web reinforcement

Due to the complexities of the mechanics of shear failure in reinforced concrete (RC) members, most current approaches for predicting shear strength are mainly empirical. Being empirical, these approaches do not physically explain the shear failure mechanism seen in practice and consequently should only be used within the bounds of the testing regimes from which they were derived; this restricts their application to innovative materials such as fibre-reinforced polymer RC beams or those with high-performance concrete. In this paper, a numerical mechanics-based segmental approach for the shear failure of RC beams with any type of reinforcement and concrete is developed; from the mechanics of the segmental approach, simplifications are made to develop closed form solutions and the resulting design equations are compared to a database of 626 steel-reinforced specimens. Further comparisons to the predictions made by the ACI, AS 3600 and FIB Model Code 2010 approaches show that the proposed approach offers improved accuracy and a reduction in scatter.