EXPERIMENTAL STUDIES ON HIGH-STRENGTH CONCRETE DEEP BEAMS

Sixteen high-strength concrete deep beams were tested to destruction. Variables considered in the investigation were shear-span to depth ratio, concrete strength of 50-120 MPa (7,250-17,400 psi), and the provision of secondary reinforcement. The investigation examined deep beam behavior and compared the experimental results with the CIRIA Guide 2 design method, the American Concrete Institute (ACI) 318 method, and the plastic truss model of Rogowsky and MacGregor, using the efficiency model proposed by Warwick and Foster. The results showed that good load predictions were obtained using the plastic truss model when combined with the Warwick and Foster efficiency factor. It is also concluded that the design methods given by CIRIA Guide 2 and ACI 318 are generally conservative for deep beams fabricated with high-strength concrete.