Shear strength model for prestressed concrete beams with steel fibres failed in shear

Abstract

This study aims to develop a shear strength model for steel-fibre-reinforced prestressed concrete (SFR-PSC) beams. A dual potential capacity model was adopted to consider the shear-resistant mechanisms of the compression and cracked tension zones at the critical section, and its formulations were modified to address the synergistic effect of prestressing and steel fibres. In the proposed model, the shear demands to be resisted by the cracked tension and intact compression zones, respectively, were estimated based on the equilibrium conditions, and their corresponding potential shear capacity curves were also defined. It is assumed in the proposed method that the shear strength of an SFR-PSC member is dominated by a specific shear-resistance mechanism whose shear demand curve reaches the limit state (i.e. corresponding potential shear capacity curve) earlier than another one. To verify the proposed method, experimental results collected from the literature were compared with those estimated by the proposed model.