Flexural and Cyclic Behaviour of RC Beams Retrofitted with Carbon Fiber Reinforced Polymer (CFRP) Fabrics

This paper explores the flexural behaviour of carbon fiber reinforced polymer (CFRP) retrofitted reinforced concrete (RC) beams. For flexural strengthening of RC beams, a total of sixteen beams were cast and tested over an effective span of 3000 mm up to failureunder static monotonic and compression cyclic loads. The beams were designed as underreinforced concrete beams. Twelve beams were retrofitted with bonded CFRP fabrics in one layer, two layers and three layers which are parallel to beam axis at the bottom under virgin condition and tested until failure; the remaining four beams were used as control specimens. Static and cyclic responses of all the beams were evaluated in terms of strength, stiffness, ductility ratio, energy absorption capacity factor, compositeness between CFRP fabrics and concrete, and the associated failure modes. The theoretical moment-curvature relationship and the load-displacement response of the retrofitted beams and control beams were predicted by using FEA software ANSYS. Comparison has been made between the numerical (ANSYS) and the experimental results. The results show that the retrofitted beams exhibit increased flexural strength, enhanced flexural stiffness, and composite action until failure.