The Journal of the Korea Contents Association (한국콘텐츠학회논문지)

The Korea Contents Association (한국콘텐츠학회)
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Characteristics of Flexural Capacity and Ultrasonic in RC member with Corroded Steel and FRP Hybrid Bar

부식된 FRP Hybrid Bar의 휨 내력 및 초음파 속도 특성

  • 최세진 (원광대학교 건축공학과) ;
  • 문진만 (한남대학교 건설시스템공학과) ;
  • 박기태 (한국건설기술연구원 구조융합연구소) ;
  • 박철우 (강원대학교 사회기반시스템공학부) ;
  • 권성준 (한남대학교 건설시스템공학과)
  • Received : 2015.03.19
  • Accepted : 2015.05.07
  • Published : 2015.08.28
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Abstract

Concrete is a attractive construction material, however durability problem occur due to steel corrosion, which leads propagation to structural safety problem. The recently developed FRP (Fiber Reinforced Plastic) Hybrid Bar has an engineering merit of both structural steel and FRP. Accelerated corrosion test for RC (Reinforced Concrete) samples with normal steel and FRP Hybriud Bar are performed and their flexural capacity is evaluated. Furthermore UV(Ultrasonic Velocity) measurement is attempted for analysis of variation of UV due to corrosion condition. After corrosion test, there is no significant reduction in RC beam with FRP hybrid bar but 11.5% of reduction in the case of normal steel is evaluated with 3.3% of UV reduction. For commercial production of FRP hybrid bar, bond strength evaluation through long-term submerged corrosion is required.

콘크리트는 내구적인 건설재료이지만 철근부식에 따라 내구성 문제가 발생하고 이는 구조적인 안전성 문제로 진전된다. 최근 들어 개발된 FRP hybrid bar는 기존의 FRP와 강재의 장점을 가진 것으로 본 연구에서는 이에 대한 촉진부식실험을 수행하여 휨내력저하를 평가하였다. 또한 촉진부식실험 전후에 초음파속도를 측정하여 부식에 따른 속도변화를 분석하였다. FRP hybrid bar를 매립한 RC 시편에서는 휨 내력저하가 발생하지 않았지만, 일반강재를 매립한 부재에서는 평균 11.5%의 휨 내력저하가 발생했으며, 3.3%의 초음파 속도 감소가 평가되었다. FRP hybrid bar의 내부식성은 매우 우수한 것으로 평가되었으나 실용화를 위해서는 장기침지에 따른 부착성검토가 필요하다.

Keywords

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