Experimental and analytical investigation of RC beams strengthened by FRP and FRCM

Document Type : Research Paper

Authors

1 Faculty of Engineering, Ferdowsi University of Mashhad, Mashhad, Iran

2 Department of Civil Engineering, Faculty of Engineering, Ferdowsi University Of Mashhad (FUM)

10.22124/jcr.2022.21288.1540

Abstract

The present study aims to compare the flexural behavior of reinforced concrete (RC) beams strengthened by fiber reinforced polymer (FRP) with that of fiber reinforced cementitious matrix (FRCM) sheets. Accordingly, 6 RC beams were manufactured and strengthened by FRP and FRCM. Other parameters such as strengthening method and tensile reinforcement ratio were investigated. The results show that in externally bonded reinforcement (EBR) method, strengthening by FRCM sheets leads to the improvement of load carrying capacity by 12.8% and 16.8%, respectively, in specimens with and compared to the specimens strengthened by FRP sheets. Furthermore, the failure mode of specimens strengthened by EBR method was debonding in case of FRP sheets while the failure mode of FRCM strengthened specimens was fiber rupture. In externally bonded reinforcement on grooves (EBROG) method, the load carrying capacity of specimens strengthened by FRP and FRCM was almost the same, while their failure mode was debonding with partial cover separation and complete cover separation. Finally, the experimental results were compared to the existing models and different code provisions. It was observed that by increasing the tensile reinforcement ratio in FRP strengthened beams, the predicted results by analytical models become closer to the experimental results.

Keywords

Main Subjects

References

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