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Composite Strips with U-Shaped CFRP Wrap Anchor Systems for Strengthening Reinforced Concrete Beams

  • Rami H. HaddadEmail author
  • Catreen S. Marji
Research paper
  • 2 Downloads

Abstract

The contribution of carbon fiber reinforced polymer (CFRP) wrap as an anchorage system of CFRP plates, used for flexural strengthening, is investigated. Eighteen concrete beams (100 × 150 × 1400 mm3) were cast and cured for 28 days before strengthening with both CFRP plates (1.2 × 50 mm2) and anchorage-used, U-shaped CFRP wraps. These were adhered on the top of the CFRP plates at different longitudinal and transverse extensions. The mechanical response of the concrete beams was examined under four-point loading including measurements of load versus deflection, bond stress versus slippage and strain in CFRP plates. Crack formation and failure modes were also monitored and characterized. End anchorage regimes, using 300-mm-long U-shaped segmented CFRP wraps, impart the best improvement to load capacity, rigidity, and toughness (up to 80, 57, and 40%, respectively) without harming tangibly ductility in terms of deflection at failure. Anchorage cases involving attaching continuous single or double layers of U-shaped CFRP wrap on the top of CFRP plates impart lower but tangible overall improvements in mechanical performance of CFRP-strengthened beams. A simple empirical model is developed to predict ultimate strain in CFRP plate based on present results before examining using available literature data. Moreover, the efficiency of the present technique is compared to that present in literature.

Keywords

Beams Composite materials Bond CFRP wrap anchorage Strain in CFRP Failure patterns 

Notes

Acknowledgements

The authors acknowledge the technical and financial support provided by Jordan University of Science and Technology (Project No. 227/2011) and the technical assistance provided by the structural and materials laboratories teams.

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Copyright information

© Iran University of Science and Technology 2019

Authors and Affiliations

  1. 1.Civil Engineering DepartmentJordan University of Science and TechnologyIrbidJordan

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