Flexural behavior of hybrid C-PET FRP-strengthened RC beams with U-strip anchorages.

In this study, a comprehensive experimental and theoretical work was conducted on the bending performance of hybrid carbon-polyethylene terephthalate (C-PET) fiber-reinforced polymer (FRP) strengthened reinforced concrete (RC) beams with U-strip anchorages. Eleven RC beams were tested under a four-point bending load to investigate the influence of stacking sequence and U-strip anchorages. The bending performance of strengthened beams was carefully examined and discussed with regard to failure mode, flexural strength, ductility coefficient, and FRP strain development. The hybrid strengthened beams with U-strip anchorages exhibited 10.54 %−21.97 % higher flexural strength and 4.30 %−206.27 % higher ductility factors than the corresponding strengthened beams without U-strip anchorages. In addition, a theoretical analysis model with high accuracy was proposed to simulate the load-deflection curves of the strengthened beams based on the section analysis and plastic hinge model. Finally, this paper evaluated the accuracy of design guidelines (including GB 50608, ACI 440.2 R, and CNR DT 200 R1) in calculating the load-bearing capacities of strengthened beams. • Flexural performance was studied for hybrid carbon-PET FRP-strengthened RC beams with U-strip anchorages. • Effect of U-strip anchorages on flexure performance was investigated and discussed. • A simple but accurate theoretical model for load-deflection curves was proposed. • The design guidelines were evaluated in calculating the load-bearing capacities of the strengthened beams. [ABSTRACT FROM AUTHOR]