콘크리트학회논문집 (Journal of the Korea Concrete Institute)

  • 제20권6호
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  • Pages.713-719
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  • 2008
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  • 1229-5515(pISSN)
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  • 2234-2842(eISSN)
한국콘크리트학회 (Korea Concrete Institute)
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수산화칼슘을 혼입한 폴리머 방청 코팅의 부식 임계치 향상에 대한 연구

A Study on Chloride Threshold Level of Polymer Inhibitive Coating Containing Calcium Hydroxide

  • 송하원 (연세대학교 사회환경시스템공학부) ;
  • 이창홍 (연세대학교 사회환경시스템공학부) ;
  • 이근주 (연세대학교 사회환경시스템공학부) ;
  • 안기용 (연세대학교 사회환경시스템공학부)
  • Song, Ha-Won (Dept. of Civil and Environmental Engineering, Yonsei University) ;
  • Lee, Chang-Hong (Dept. of Civil and Environmental Engineering, Yonsei University) ;
  • Lee, Kewn-Chu (Dept. of Civil and Environmental Engineering, Yonsei University) ;
  • Ann, Ki-Yong (Dept. of Civil and Environmental Engineering, Yonsei University)
  • 발행 : 2008.12.31
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초록

철근콘크리트내의 염분침투저항성을 향상시키기 위한 방안으로 다양한 철근 방청 코팅기법이 개발되어져왔다. 이와 관련된 가장 일반적인 방법으로서는 방청철근의 사용, 시멘트 슬러리 코팅 및 폴리머계 복합수지를 사용한 철근 코팅 및 에폭시 코팅등을 들 수 있다. 여기서 폴리머계 시멘트 코팅이 철근의 부동태 피막 및 장벽보호를 동시에 꾀함과는 달리 시멘트 슬러리 코팅의 경우는 철근의 부동태 보호에, 에폭시 코팅의 경우는 철근의 장벽보호에 주 목적을 두고 있다. 더욱이 에폭시코팅의 경우는 시공상의 오차로 인해 철근의 비부착 문제를 일으키게 되며 이는 국부부식의 위험을 증대시키게 된다. 본 연구에서는 철근-콘크리트 계면에서, 최대 20%의 수산화칼슘의 증가를 통한 방청기법이 적용되어졌다. 수산화칼슘의 경우 높은 pH저하저항성을 가지고 있어 염해부식환경에 대해 알칼리성 환경이 유지하도록 하는 역할을 한다. 본 논문은 철근/콘크리트 계면에서의 pH 저하 저항성의 향상 방안으로서, 수산화칼슘의 첨가에 따른 철근 방청코팅의 향상 효과를 시험하였다. 또한 수산화칼슘을 혼입한 폴리머 코팅의 염화물임계치 (CTL)에 관해서도 비교분석을 하였다.

Various types of coatings have been developed for use as reinforcement in concrete and to resist chloride environment. The most commonly used coatings are inhibited and sealed cement slurry coating, cement polymer compositing coating and epoxy coating. Cement slurry offers passive protection, epoxy coating offers barrier protection whereas polymer coating offers both passive protection and barrier protection. Moreover, damage during handling of the steel may result in disbondment of the epoxy coating, which would increase the risk of localized corrosion. In the present study, inhibiting technique was used to increase the calcium hydroxide content at the interface up to 20%. Calcium hydroxide provides a high buffering capacity that resists a local fall in pH and thus maintains the alkaline environment necessary to prevent chloride corrosion. This study examines the use of a calcium hydroxide coating on the steel surface to enhance the pH buffering capacity of steel-concrete interface. Finally, the chloride threshold level (CTL) of polymer inhibitive coating calcium hydroxide is evaluated.

키워드

참고문헌

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피인용 문헌

  1. A Study on the Anti-corrosion Properties of Organic and Inorganic Inhibitor by Electrochemical Evaluation Method in Saturated Aqueous Solution of Calcium Hydroxide vol.17, pp.4, 2013, https://doi.org/10.11112/jksmi.2013.17.4.066