Experimental Verification of Reinforced Concrete Beam with FRP Rebar

FRP 보강콘크리트 보의 휨거동에 관한 실험적 연구

  • 오홍섭 (국립진주산업대학교 토목공학과) ;
  • 안광열 (남해전문대학)
  • Received : 2007.04.18
  • Published : 2008.05.30

Abstract

The use of fiber reinforced polymer (FRP) composites is significantly growing in construction and infrastructure applications where durability under harsh environmental conditions is of great concern. In order to examine the applicability of FRP rebar as a reinforcement in flexural member, flexural tests were conducted. 12 beams with different FRP materials such as CFRP, GFRP and Hybrid FRP and reinforcement ratio were tested and analyzed in terms of failure mode, moment-deflection, flexural capacity, ductility index and sectional strain distribution. The test results were also compared with the theoretical model represented in ACI 440.1R06. Test results indicate that the flexural capacity of the beams reinforced by FRP bars can be accurately predicted using the ultimate design theory. They also show that the current ACI model for computing the deflection overestimates the actual deflection of GFRP series and underestimates the deflection of CFRP series.

혹독한 자연환경하에서의 구조물의 내구성이 주요한 관심사도 대두되면서 건설분야에서 섬유강화폴리머의 사용이 점차 증가하고 있는 추세이다. 본 연구에서는 FRP bar를 휨부재의 휨보강근으로서의 적용가능성을 평가하기 위하여 휨실험을 수행하였다. 탄소섬유, 유리섬유 및 탄소와 유리섬유를 혼합한 hybrid 섬유 보강근을 사용하여 보강량을 변화시킨 12개의 실험체를 제작하여 실험을 수행하였으며, 그결과는 파괴형태, 모멘트-변위, 휨강도, 연성지수 및 단면에서의 변형율분포 등에 대하여 분석하였다. 실험결과는 ACI 기준에 제시된 모델과 비교하였으며, 전체적으로 보의 휨강도는 강도설계이론에 의한 결과와 거의 유사한 것으로 나타났다. 그러나 처짐의 경우에는 유리섬유의 경우는 이론이 과대평가 되었으며, 탄소섬유는 과소평가되는 것으로 나타났다.

Keywords

References

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