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콘크리트 환경과 고온의 복합환경이 FRP 보강근의 계면전단성능에 미치는 영향

The Combined Effect of Concrete Environment and High Temperature on Interlaminar Shear Strength of FRP Reinforcement

  • 문도영 (경성대학교 토목공학과) ;
  • 오홍섭 (경남과학기술대학교 토목공학과)
  • Moon, Do-Young (Dept. of Civil Engineering, Kyungsung University) ;
  • Oh, Hong-Seob (Dept. of Civil Engineering, Gyeongnam National Univ. of Sci. and Tech.)
  • 투고 : 2011.07.11
  • 심사 : 2011.11.16
  • 발행 : 2011.12.31

초록

FRP 보강근의 화재 노출시 내구성능에 대한 연구들은 고온 노출이 인장성능에 미치는 영향에 대한 분석이 대부분을 차지한다. 그러나, 신설 구조물에 삽입된 FRP 보강근은 먼저 콘크리트 내에서 습윤환경 및 알칼리에 의한 성능저하가 발생하며, 이와 같은 FRP 보강 콘크리트 구조물에 화재가 발생하면, 보강근은 고온에 노출된다. 그러므로 화재에 의해 손상 받은 FRP 보강근의 평가시에는 콘크리트 환경과 고온에 의한 영향을 동시에 고려하여야 한다. 이 연구에서는 장기간동안 용액에 노출된 FRP 보강근에 $60^{\circ}C$, $100^{\circ}C$, $150^{\circ}C$$300^{\circ}C$의 온도를 가하고, 계면전단강도를 측정, 비교 하였다. 실험 결과에 따르면, 환경과 고온의 복합영향이 FRP 보강근의 역학적 특성에 미치는 영향이 환경만의 영향 또는 고온만의 영향 보다 큰 것으로 나타났다.

Most experimental studies on durability of FRP reinforcements subjected to high temperature have focused on the effect of high temperature only on tensile properties. But FRP reinforcement used in newly constructed concrete structure is first degraded by moisture and alkaline environment of concrete. When the structure is subjected to fire, the degraded FRP reinforcement is exposed to high temperature. Therefore, the effects of concrete environment and high temperature should be simultaneously considered for evaluation of FRP reinforcement damaged by fire. In this study, FRP reinforcements submerged in simulated solutions of pH 12.3 and 7 for extended period of time were subjected to temperatures of $60^{\circ}C$, $100^{\circ}C$, $150^{\circ}C$, and $300^{\circ}C$ to be examined. In order to investigate the effect of the high temperature, interlaminar shear strengths were measured and compared to those of control ones. The experimental results demonstrated that the combined effect of concrete environment and high temperature on properties of FRP reinforcement was more significant than the effect of high temperature or concrete environment solely.

키워드

참고문헌

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피인용 문헌

  1. Prediction of Long-term Residual Inter-laminar Shear Strength of Thermally Damaged GFRP Rebar vol.18, pp.3, 2014, https://doi.org/10.11112/jksmi.2014.18.3.108
  2. Critical Temperature for Inter-Laminar Shear Strength and Effect of Exposure Time of FRP Rebars vol.25, pp.1, 2013, https://doi.org/10.4334/JKCI.2013.25.1.045