This paper presents numerical research on carrying capacity of reinforced concrete (RC) beams strengthened by external flexural and flexural-shear carbon fiber reinforced polymer (CFRP). First the model is verified with previous published work to ensure that the results obtained from FE by using ANSYS are correct, the results were in accordance with those from published experiments with variation not more than 20%. The FRP layers and thickness were considered as main parameters. Furthermore, the work carried out examined both the flexural and flexural-shear strengthening capacities of retrofitted RC beams and indicated how different strengthening arrangements of CFRP sheets affect the mechanical behavior of the strengthened RC beams. Moreover, the stiffness, ultimate strength and hardening behavior of the RC beam for different strengthening schemes are investigated by the established finite element model. The results show that the FRP layer and thickness have greater effect for increasing the load caring capacity of beams with increasing of 60%, 40%, and 30% for three, two, and one layer, respectively, compared with those without strengthening.
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