Abstract:

This paper aims at the mechanical characteristics of the reinforced concrete (RC) beams strengthened with carbon fiber sheet/ aramid fiber sheet (CFS/ AFS) , a new hybrid strengthening method. In the investigation ,the nonlinear finite element analyses of the single-layer and double-layer strengthening models for the RC beams are made by establishing the constitutive equations of different materials. Then , the effects of the fibre sheet type and the sheet length on the bending stiffness , initial cracking loads and failure loads of the beams are analyzed. Moreover, a comparative analysis is performed , finding that the calculated results are consistent with the experimental ones. It is indicated that the hybrid strengthening by using CFS and AFS may result in a good hybrid effect and may sufficiently bring the high strength of CFS into play.

Key words: reinforced concrete beam, hybrid fiber sheet, nonlinear finite element, strengthening