Earthquakes and Structures

  • 제20권1호
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  • Pages.123-132
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  • 2021
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  • 2092-7614(pISSN)
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  • 2092-7622(eISSN)
테크노프레스 (Techno-Press)
권호 표지
DOI QR코드

DOI QR Code

Strengthening of deficient RC joints with diagonally placed external C-FRP ropes

  • Karayannis, Chris G. (Department of Civil Engineering, Democritus University of Thrace) ;
  • Golias, Emmanouil (Department of Civil Engineering, Democritus University of Thrace)
  • 투고 : 2020.12.29
  • 심사 : 2021.01.26
  • 발행 : 2021.01.25
⟨ 이전 논문 다음 논문 ⟩

초록

Deficient beam-column joints of reinforced concrete (RC) structures designed to older practices and codes often lead to destructive local or global failures. A strengthening technique for these joints based on the use of the new and innovative Carbon-FRP (C-FRP) ropes is presented and investigated. The C-FRP ropes are diagonally placed in superficial notches on the two sides of the joint. Two full scale external substandard joint subassemblages with the same characteristics, one unstrengthened and one strengthened with diagonally applied C-FRP ropes, are constructed and tested in cyclic loading. Special attention has been given to the elaboration of the acquired test measurements. The extracted conclusions are based on the comparative study of the hysteretic responses of the specimens, the observed maximum load envelopes, the comparisons of the joint body shear deformations as measured using diagonally mounted LVTDs, the calculated nominal principal stresses developed in the joint regions, the assessed joint damage as expressed by the damage index by Park and Ang and finally the calculated values of the equivalent damping ratio. From these comparisons it is concluded that application of diagonally mounted C-FRP ropes on the two sides of the joint body of exterior connections is an efficient easy-to-apply technique for the strengthening of substandard RC joints.

키워드

참고문헌

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피인용 문헌

  1. Effectiveness of the Novel Rehabilitation Method of Seismically Damaged RC Joints Using C-FRP Ropes and Comparison with Widely Applied Method Using C-FRP Sheets-Experimental Investigation vol.13, pp.11, 2021, https://doi.org/10.3390/su13116454
  2. Application of X-Shaped CFRP Ropes for Structural Upgrading of Reinforced Concrete Beam-Column Joints under Cyclic Loading-Experimental Study vol.9, pp.7, 2021, https://doi.org/10.3390/fib9070042
  3. Behaviour of repaired RC beam-column joints using welded wire mesh and jacketed with polymer modified mortar vol.21, pp.1, 2021, https://doi.org/10.12989/eas.2021.21.1.079