Shear strengthening of reinforced concrete beams using various techniques

This paper presents the results of an experimental investigation for enhancing the shear capacity of reinforced concrete beams using different techniques. A total of eleven beams were tested in this program. Two series of beams were designed; in the first series, beams were designed in such a way that the strengthened beams fail in ductile flexural mode thereby avoiding the brittle shear failure. The second series of beams were designed to fail in shear mode; to assess the actual increase in shear strength by devised strengthening techniques. Two beams were kept as control beams; whereas other beams were strengthened with steel brackets, steel plates, vertical strips and externally anchored stirrups. All techniques were found effective in enhancing the shear strength of beams. However, the externally anchored stirrups were found to be the most effective. Beam strengthened using this technique failed at a load almost 117% higher than the control beam. The epoxy bonded steel plates provided an average of 72% increase in shear capacity as compared to the control beams.