대한건축학회논문집 (Journal of the Architectural Institute of Korea)

  • 제39권3호
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  • Pages.231-238
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  • 2023
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  • 2733-6239(pISSN)
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  • 2733-6247(eISSN)
대한건축학회 (Architectural Institute of Korea)
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FRP판으로 휨 보강된 철근콘크리트 보의 장기거동

Long-term Behavior of Reinforced Concrete Beams Flexurally Strengthened with FRP Strip

  • Seo, Soo-Yeon (Dept. of Architectural Engineering, Korea National University of Transportation) ;
  • Tran, Hi Van (Dept. of Architectural Engineering, Korea National University of Transportation) ;
  • Kim, Kang Su (Dept. of Architectural Engineering, University of Seoul) ;
  • Yun, Hyun-Do (Dept. of Architectural Engineering, Chungnam National University) ;
  • Lee, Gun-Cheol (Dept. of Architectural Engineering, Korea National University of Transportation)
  • 투고 : 2022.12.05
  • 심사 : 2023.02.28
  • 발행 : 2023.03.30
⟨ 이전 논문 다음 논문 ⟩

초록

The purpose of this study is to evaluate the long-term behavior of RC beams reinforced by fiber reinforced polymer (FRP) strip such as near-surface mounted retrofit (NSMR) and externally bonded retrofit (EBR). The 30% loads of nominal strength of the RC beams were applied and continued for up to 49 days. The loads were increased up to 55% of the nominal strengths of RC beams at 50 days after performing flexural retrofit by using FRP with the planned retrofit methods and have been kept for almost one year. During all loading periods, the deflections and the strains of rebars and FRPs were measured at least once every week. The long-term behavior of all specimens was evaluated and the deflection variations were predicted by considering the long-term effect on the nonlinear sectional analysis result of the reinforced RC beams. As a result, in the specimen reinforced with partially de-bonded NSM FRP, the strains of the FRP strip were not concentrated on the center of the beam and the magnitude at the center was less than that with the fully bonded FRP. In addition, it is possible to properly simulate the deflections of the beams strengthened with FRP exposed to a long-term load by considering the long-term effect on the sectional analysis result.

키워드

과제정보

본 연구는 2022년도 과학기술정보통신부 기초연구실지원사업 (No. 2021R1A4A2001964)과 기초연구지원사업 (No.2022R1A2C2004460)의 지원을 받아 수행된 결과임.

참고문헌

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