Cyclic behavior of continuous reinforced concrete haunched beams with transverse reinforcement designed to fail in shear

Research results and interpretations of the testing of five prototype continuous reinforced concrete beams (four haunched and one prismatic) designed to develop a shear failure under increasing cyclic loading are presented. Subject beams were tested with minimum shear reinforcement. The studied haunched length was one-third the effective span of the beam. The considered angles of slope of haunch from horizontal vary from 0° (prismatic) to 10°. Increasing cyclic tests were displacement-controlled, and two cycles at the same displacement were set in the displacement history which considers a geometrical increment of target displacements. Differences in the cyclic shear behavior of haunched beams with respect to prismatic beams were monitored in terms of cracking patterns, stiffness and strength degradation and energy dissipation. The obtained results from the increasing cyclic testing in continuity conditions allow one to corroborate what it was observed in previous testing for simply supported beams: reinforced concrete haunched beams seem to be more efficient than reinforced concrete prismatic beams, even when they fail in shear.