Journal of the Architectural Institute of Korea Structure & Construction (대한건축학회논문집:구조계)

Architectural Institute of Korea (대한건축학회)
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Shear Strengthening by Externally Post-tensioning Steel Rods in Damaged Reinforced Concrete (RC) Beams

손상입은 철근콘크리트 보의 포스트텐셔닝 강봉을 이용한 전단 보강

  • 이수헌 (경북대학교 융복합시스템공학부) ;
  • 이희두 (경북대학교 건설환경에너지공학부) ;
  • 박성근 (경북대학교 건설환경에너지공학부) ;
  • 신경재 (경북대학교 건설환경에너지공학부)
  • Received : 2017.06.05
  • Accepted : 2017.10.28
  • Published : 2018.01.30
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Abstract

This experimental investigation was conducted to observe the shear strengthening behavior of pre-damaged reinforced concrete (RC) beams strengthened with externally post-tensioning steel rods. A total of six simply supported beams - two control beams and four post-tensioned beams using external steel rods - were tested to failure in shear. The external steel rods of 18 mm or 28 mm diameter were respectively employed as post-tensioning material. The four post-tensioned beams have a V-shaped profile with a deviator (or saddle pin) located at mid-span, and the post-tensioning system increased the low load-carrying capacity and overcame a little bit of deflection caused by damage. Concretely, the load-carrying capacity and flexural stiffness were respectively increased by about 25~57% and 263~387% due to the post-tensioning when compared with the unstrengthened control beams.

Keywords

Acknowledgement

Supported by : 한국연구재단

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