Structural Engineering and Mechanics

  • 제64권1호
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  • Pages.135-143
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  • 2017
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  • 1225-4568(pISSN)
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  • 1598-6217(eISSN)
테크노프레스 (Techno-Press)
권호 표지
DOI QR코드

DOI QR Code

Shear-strengthening of RC continuous T-beams with spliced CFRP U-strips around bars against flange top

  • Zhou, Chaoyang (School of Civil Engineering, Central South University) ;
  • Ren, Da (School of Civil Engineering, Guangzhou University) ;
  • Cheng, Xiaonian (School of Civil Engineering, Central South University)
  • 투고 : 2016.11.18
  • 심사 : 2017.08.17
  • 발행 : 2017.10.10
⟨ 이전 논문 다음 논문 ⟩

초록

To upgrade shear performance of reinforced concrete (RC) beams, and particularly of the segments under negative moment within continuous T-section beams, a series of original schemes has been proposed using carbon fibre-reinforced polymer (CFRP) U-shaped strips for shear-strengthening. The current work focuses on one of them, in which CFRP U-strips are wound around steel bars against the top of the flange of a T-beam and then spliced on its bottom face in addition to being bonded onto its sides. The test results showed that the proposed scheme successfully provided reliable anchorage for U-strips and prevented premature onset of shear failure due to FRP debonding. The governing shear mode of failure changed from peeling of CFRP to its fracture or crushing of concrete. The strengthened specimens displayed an average increase of about 60% in shear capacity over the unstrengthened control one. The specimen with a relatively high ratio and uniform distribution of CFRP reinforcement had a maximum increase of nearly 75% in strength as well as significantly improved ductility. The formulas by various codes or guidelines exhibited different accuracy in estimating FRP contribution to shear resistance of the segments that are subjected to negative moment and strengthened with well-anchored FRP U-strips within continuous T-beams. Further investigation is necessary to find a suitable approach to predicting load-carrying capacity of continuous beams shear strengthened in this way.

키워드

과제정보

연구 과제 주관 기관 : Natural Science Foundation of P.R.China, Natural Science Foundation of Hunan Province, Central South University

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피인용 문헌

  1. Interfacial stresses in reinforced concrete cantilever members strengthened with fibre-reinforced polymer laminates vol.23, pp.2, 2017, https://doi.org/10.1177/1369433219868933
  2. A neuro-fuzzy approach to predict the shear contribution of end-anchored FRP U-jackets vol.26, pp.5, 2017, https://doi.org/10.12989/cac.2020.26.5.397