Shear strengthening of reinforced concrete continuous beams

This paper presents the results of an experimental investigation to evaluate the contribution of carbon-fibre-reinforced polymer sheets in enhancing the shear strength of continuous reinforced concrete beams. A total of five, two-span concrete continuous beams with rectangular cross-section were tested. One beam without strengthening was used as the control and the other four beams were strengthened with different arrangements of polymer sheets. The variables selected were various wrapping schemes and anchorage length of the polymer sheet. The aim was to develop a better understanding of the shear contribution of polymer and to investigate the potential for cost savings by minimising the area of externally bonded polymer sheets. Test results were compared with four existing shear prediction models available in the literature. The results indicate that the polymer sheet significantly enhanced the shear strength of the beams, and that the area of polymer sheet can be minimised with marginal compromise on the shear carrying capacity of strengthened concrete beams.