ABSTRACT
In this research, experimental research was carried out to assess the flexural and shear capacities of RC beams strengthened with different amount of carbon fibre reinforced polymer laminates at the tension face and U-strips. Twelve rectangular RC beams of cross-sectional dimension 150x150x750mm were cast and three were un-strengthened and used as reference beams and the remaining nine were strengthened with different amount of CFRP varying from single to triple layers and all were tested to failure under three point bending test. The increase of ultimate strength provided by the bonded CFRP laminates was assessed and failure modes identified and compared to the un-strengthened RC beams. The results indicated that the flexural capacity of the beams were significantly improved as the amount of the laminates increases. The increment ranges from 20% to 52% for single to triple layers laminates and also the shear capacity of the strengthened beam increased as compared to the un-strengthened beams. The experimental CFRP shear strength contribution were also compared with the predicted resultsand the results obtained closely agreed with the experimental results. It was concluded that the attachment of CFRP laminates has substantial influence on the performance improvement of CFRP strengthened RC beams in both shear and flexure but this increase is accompanied with the reduction in ductility due to the restraining effect offered by the CFRP material to the concrete surface.