Flexural behavior of reinforced concrete (RC) beams strengthened with carbon fiber reinforced polymer (CFRP) and ECC

In this study, the reinforced concrete (RC) beams were strengthened by use of carbon fiber reinforced polymer (CFRP) and engineering cementitious composite (ECC). The flexural behavior of the strengthened RC beams was investigated experimentally, and analytical prediction methods were used to verify the experimental results. The experimental results showed that, the premature delamination between CFRP plate and concrete occurred if the beam was solely reinforced by CFRP, nevertheless, this can be effectively prevented by the composite use of CFRP and ECC. Compared with reference beam, the CFRP-ECC composite strengthened technique significantly enhanced the cracking load, yield load, and ultimate load of beams up to 23-31%, 4-6%, and 5-10%, respectively, in addition, the stiffness, ductility, and energy absorption capacity (EAC) can also be enhanced upon the composite strengthening. In final, the prediction model has high accuracy, and the error variation within 5% when comparing the predicted and tested values of flexural bearing capacity.