Characterization and Shear Strength Prediction of Reinforced Concrete Deep Beams ? A Review

Reinforced concrete deep beams are structural elements that transfer heavy gravity loads predominantly through shearing action to their supports. A significant feature of deep beams is their high shear strength. This is attributed to the internal tied-arch mechanism which conveys the load directly to the supports through concrete compressive struts. Different definitions have been proposed for RC deep beams by various researchers and codes of practice that differ in concept. Also, various shear strength prediction models have been developed by several researchers and codes for the estimation of the shear strength of deep beams through analytical and extensive test programs. However, there seems to be no agreement on which definition adequately classifies what a deep beam is and which model produces best results close to experimental values, the shear strength of this class of beams. The study compared the definitions and evaluated the shear capacity models of deep beams per different code provisions based on data from 210 deep beams obtained from the literature. It was found that the ACI-318 (2008) code definition concept gives the most realistic characterization of a deep beam, whilst its shear strength model, based on the strut-and-tie model approach, provides the best prediction for the shear strength of a deep beam.