SHEAR STRENGTH PREDICTION BY MODIFIED PLASTICITY THEORY FOR SHORT BEAMS

Two series of short beam tests, comprising high-strength concrete (HSC) and varying degrees of vertical shear reinforcement, were reinvestigated by considering the failure mechanism approach in limit analysis and concrete plasticity. Both original plastic and crack sliding solutions were applied to predict shear resistance. The latter solutions were recently introduced and modified because the yield line can develop along the critical diagonal crack. This results in a yield line at a certain distance from the support and reduced sliding resistance. Due to the larger slip involved at the crack interface in HSC, crack sliding solutions are more likely to capture the observed behavior. By considering the effect of crack sliding, the effectiveness factor of concrete can be reduced, and this procedure generated other solutions for the treatment of beams with stirrups. Good agreement with the observed strength and contribution of vertical shear reinforcement was achieved using the crack sliding model.