Journal of the Korea Concrete Institute (콘크리트학회논문집)

Korea Concrete Institute (한국콘크리트학회)
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Evaluation on Chloride Binding Capacity of Mineral Mixed Paste Containing an Alkaline Activator

알칼리 활성화제를 사용한 무기질 혼합 페이스트의 염화물이온 고정화 평가

  • Cho, Gyu-Hwan (Korea Institute of Civil Engineering and Building Technology, Fire Research Institute) ;
  • Yeo, In-Hwan (Korea Institute of Civil Engineering and Building Technology, Fire Research Institute) ;
  • Ji, Dong-Hun (Korea Maritime and Ocean University, Department of Architecture and Ocean Space)
  • 조규환 (한국건설기술연구원 화재안전연구소) ;
  • 여인환 (한국건설기술연구원 화재안전연구소) ;
  • 지동헌 (한국해양대학교 해양공간건축학과)
  • Received : 2015.07.29
  • Accepted : 2016.01.22
  • Published : 2016.04.30
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Abstract

It is possible to achieve high strength ranging from 40 MPa to 70 MPa in alkali-activated slag concrete (AASC), and AASC is also known to have a finer pore structure due to its high latent hydraulicity and fineness of slag cement, which makes it difficult for chloride ions to penetrate. Electrophoresis is mostly used to calculate the effective diffusion coefficient of chloride ions, and then to evaluate resistance to salt damage. Few studies have been conducted on the fixation capacity of chloride ions in AASC. For this reason, in this study the chloride fixation within the hardened paste was evaluated according to the type and the amount of alkaline activators. As a result, it was revealed that among the test specimens, the chloride fixation was greatest in the paste containing $Na_2SiO_3$. In addition, it was found that as more activator was added, a higher level of chloride fixation was observed. Through this analysis, it can be concluded that the type and the amount of alkaline activators have a high correlation with the amount of C-S-H produced.

현재 알칼리 활성 슬래그 콘크리트(AASC)는 약 40~70 MPa의 고강도화가 가능하며, 슬래그의 미세 분말도 및 잠재수경성으로 인해 공극이 치밀한 특성으로 염화물이온의 침투가 어려운 것으로 알려져 있다. 하지만 전기영동법을 사용하여 염화물이온의 유효 확산계수를 구해 염해저항성을 평가하는 경우가 대부분으로 AASC 속의 염화물이온 고정화에 대한 연구는 전무한 실정이다. 이에 본 연구에서는 알칼리 활성화제의 종류 및 첨가량에 따른 경화페이스트내의 염화물이온 고정화능력을 평가하였다. 그 결과로 $Na_2SiO_3$을 사용한 페이스트가 가장 높은 고정화능력을 나타내었으며 활성화제 첨가량이 많을수록 고정화가 높은 것으로 나타났다. 이는 활성화제 종류 및 첨가량에 따라 생성되는 경화조직인 C-S-H 생성 정도와 크게 관련성이 높은 것으로 판단된다.

Keywords

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