Coupled flexural–shear retrofitting of RC beams using CFRP straps

This paper reports on an experimental investigation carried out to investigate the coupling of shear–flexural strengthening of RC beams. The presence of shear straps to enhance shear strength has the dual benefit of delaying debonding of CFRP sheets used for flexural strengthening. Six RC beams were tested; having various combinations of CFRP sheets and straps in addition to an unstrengthened beam as control test. The instrumentations used in these tests cover the strain measurements in different CFRP layers and located along the span, in addition to the slip occurring between the concrete and the CFRP sheets. Test results and observations showed that a significant improvement in the beam strength is gained due to the coupling of CFRP straps and sheets. Further, a more ductile behaviour is obtained as the debonding failure is prevented.