Estudio sobre la propagación de fisuras de cortante en elementos de hormigón armado sin cercos

Study of shear cracks propagation in reinforced concrete elements without stirrups

This paper presents the results of a very recent experimental research program aimed at investigating mixed-mode (shear) fracture of reinforced concrete in beams without stirrups. Particularly the tests were designed to disclose the influence of the size and amount of reinforcement in the shear cracks propagation. 24 beams reinforced of three different sizes and reinforced with several reinforcement percentages were tested. The results show the influence of the reinforcement ratio and beam size in the crack trajectories, damage localization and failure load. Finally a simple model to disclose influence of size effect and reinforcement ratio in the cracking and failure is proposed. These experiments may help to understand the mechanisms of crack initiation and propagation through reinforcing bars of shear cracks in beams without stirrups.