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An Experimental Study on Bond Strength Characteristics of CFRP Depending on Moisture Content of Concrete

콘크리트 함수율에 따른 CFRP의 부착강도 특성에 관한 실험적 연구

  • Kim, Ju-Sung (Department of Architectural Engineering, Mokwon University) ;
  • Kim, Young-Jin (Research Center, Korea Concrete Institute) ;
  • Park, Sun-Gyu (Department of Architectural Engineering, Mokwon University)
  • 김주성 ;
  • 김영진 ;
  • 박선규
  • Received : 2024.09.26
  • Accepted : 2024.10.15
  • Published : 2024.10.20

Abstract

Reinforced concrete structures are vulnerable to the corrosion of reinforcing steel, which is typically caused by the neutralization of concrete and the presence of surrounding chlorides in various environmental conditions. This corrosion leads to cracking in the concrete, thereby reducing durability of the structure and shortening its lifespan. To address this issue, there has been an increasing interest in research on Fiber Reinforced Polymers(FRP), particularly Carbon Fiber Reinforced Polymer(CFRP). CFRP, composed of carbon fibers, is noted for its lightweight properties, outstanding tensile strength, and high elastic modulus. It also offers excellent corrosion resistance and durability against weathering. Despite the potential benefits, the data on CFRP's performance and integration into reinforced concrete structures remain limited. This study contributes fundamental data regarding the application of CFRP, highlighting its advantages and exploring its practical implications. A significant finding from this research is that concrete specimens cured underwater exhibited superior bond strength compared to those cured under dry conditions.

철근콘크리트 구조물은 여러 환경에 의해 콘크리트 중성화 및 주위 염화물로 인해 철근 부식이 발생하는 문제점을 가지고 있다. 철근의 부식으로 인해 콘크리트 균열이 발생되며, 내구성을 저하시키는 문제점이 있다. 이를 해결하기 위해 FRP에 대한 연구가 지속적으로 수행되고 있다. FRP 종류 중 CFRP는 높은 인장강도와 탄성계수가 뛰어나다는 장점이 있으며, 내식성과 내후성이 우수하다는 특징을 가지고 있다. 이러한 CFRP에 대한 데이터는 미비한 실정이며, 본 연구는 철근콘크리트 구조물에 적용하기 위한 기초적인 데이터를 제공하기 위해 수행된 것이다. 본 연구의 범위 내에서는 콘크리트 함수상태에 따라서 수중양생의 부착강도 시험체가 기건양생의 부착강도 시험체보다 높은 부착강도를 보였다.

Keywords

Acknowledgement

This work is supported by the Korea Agency for Infrastructure Technology Advancement(KAIA) grant funded by the Ministry of Land, Infrastructure and Transport(RS-2021-KA163381).

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