Shear strength of high-strength concrete dapped-end beams

In this study, 12 high-strength concrete dapped-end beams were tested to study the effects on shear strength of dapped-end beams of the concrete strength, the amount of main dapped-end reinforcement, and the nominal shear span-to-depth ratio. The test results indicate that the shear strength of dapped-end beams increases with the increase of the concrete strength, the amount of main dapped-end reinforcement, and the decrease of nominal shear span-to-depth ratio. An analytical model for determining the shear strength of reinforced concrete dapped-end beams is also proposed. Both the shear strengths predicted by the proposed model and the approach of the PCI Design Handbook are compared with test results of this study and those of Mattock and Chan (1979). The comparison shows that the proposed model can predict the shear strength of reinforced concrete dapped-end beams more accurately than the approach of the PCI Design Handbook.