Evaluation of Load Capacity Reduction in RC Beam with Corroded FRP Hybrid Bar and Steel

철근부식을 고려한 FRP Hybrid Bar 및 일반 철근을 가진 RC 보의 내력저하 평가

  • Received : 2015.07.28
  • Accepted : 2015.10.25
  • Published : 2016.03.01


Steel corrosion is a very significant problem both to durability and structural safety since reinforcement has to support loads in tensile region in RC(Reinforced Concrete) member. In the paper, newly invented FRP Hybrid Bar and normal steel are embedded in RC beam member, and ICM (Impressed Current Method) is adopted for corrosion acceleration. Utilizing the previous theory of Faraday's Law, corrosion amount is calculated and flexural tests are performed for RC beam with FRP Hybrid Bar and steel, respectively. Corrosion amount level of 4.9~7.8% is measured in normal RC member and the related reduction of flexural capacity is measured to be -25.4~-50.8%, however there are no significant reduction of flexural capacity and corrosion initiation in RC samples with FRP Hybrid Bar due to high resistance of epoxy-coated steel to corrosion initiation. In the accelerated corrosion test, excellent performance of anti-corrosion and bonding with concrete are evaluated but durability evaluation through long-term submerged test is required for actual utilization.


Durability;Steel corrosion;Steel;FRP Hybrid Bar;Flexural capacity


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Grant : FRP Hybrid Bar를 활용한 해양항만구조물 수명향상기술 개발

Supported by : 한국건설기술연구원