Journal of the Architectural Institute of Korea (대한건축학회논문집)

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

화재손상을 입은 철근콘크리트 보에서 외적 포스트텐셔닝강봉의 전단 보강

  • Lee, Swoo-Heon (Department of Convergence and Fusion System Engineering, Kyungpook National University)
  • 이수헌 (경북대학교 융복합시스템공학과)
  • Received : 2022.11.17
  • Accepted : 2022.12.19
  • Published : 2023.01.30
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Abstract

The purpose of this study is to discuss the applicability, strengthening effect and improvements when an externally post-tensioned steel rod system is applied to a fire-damaged reinforced concrete (RC) beam. A total of twelve specimens were prepared in three groups and tested to fail. Group one was not heated, and group two and group three were heated to 700℃ and 1,000℃, respectively. In each group, one beam without externally post-tensioned steel rods was designated as a control beam and three beams had the externally post-tensioned steel rods of 18 mm, 22 mm or 28 mm in diameter. The initial effective tension of about 2,000𝜇ε was applied to the steel rods. Test results indicated that this can be applied to fire-damaged RC because externally post-tensioning increased the load-carrying capacity by more than 67%. However, additional reinforcement is required in the part where the deviator and anchorage are installed since the concrete surface is weakened by moisture evaporation at high temperatures.

Keywords

Acknowledgement

이 성과는 정부(과학기술정보통신부)의 재원으로 한국연구재단의 지원을 받아 수행된 연구임(No. 2021R1F1A1062907).

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