Journal of the Korea Institute of Building Construction (한국건축시공학회지)

The Korean Institute of Building Construction (한국건축시공학회)
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Evaluation of Chloride Attack Resistibility of Heavyweight Concrete Using Copper Slag and Magnetite as Aggregate

동슬래그 및 자철석을 골재로 사용한 중량 콘크리트의 회파블록 적용을 위한 염해저항성 평가

  • Moon, Hoon (Department of Architectural Engineering, Pukyong National University) ;
  • Kim, Ji-Hyun (Department of Architectural Engineering, Pukyong National University) ;
  • Lee, Jae-Yong (Department of Architectural Engineering, Pukyong National University) ;
  • Chung, Chul-Woo (Department of Architectural Engineering, Pukyong National University)
  • Received : 2017.09.27
  • Accepted : 2017.11.23
  • Published : 2017.12.20
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Abstract

Recently, the coastal area has become the popular place for infrastructure development. To provide a beautiful scenary of costal area to nearby facilities without any hinderance, and also to protect those facilities from the sea water overflow, it is necessary to develop a new type of wave dissipating block, which is a turning wave block. It is noticeable that the top of the turning wave block is flat and thus can provide spaces for various purposes. However, the unit weight of the block decreases due to the presence of pipeline that is installed for turning the direction of the waves. In order to mitigate such problem, a heavyweight concrete needs to be used to increase the resistance against tidal waves. The copper slag and magnetite were used as a source of fine and coarse aggregate, respectively. The 28 day compressive strength of concrete incorporating ordinary and heavyweight aggregate did not show significant differences. It should be noted that the chloride ion penetration resistance was evaluated using NT-BUILD 492 rather than ASTM C 1202 method because concrete incorporating magnetite as a coarse aggregate showed excessive current flow by ASTM C 1202 method. According to the results from NT Build 492 method, which uses the penetration depth of chlorine ions to obtain chloride ion diffusivity, the heavyweight concrete incorporating the copper slag and the magnetite showed the best resistance against the chloride ion penetration. Therefore, it is reasonable to say that heavyweight concrete made with copper slag and magnetite can be used for production of turning wave block.

최근 국내에서는 다양한 형태로 연안이 개발되고 있다. 이에 따라 안전사고를 예방하고 경관을 저해시키지 않는 새로운 소파블록의 개발이 요구되고 있다. 회파블록은 상부가 평탄하여 친수공간으로 활용이 가능하지만, 구조 내부에 존재하는 회파관으로 인해 중량손실이 발생한다. 따라서 이에 대응하기 위해 중량콘크리트를 사용하여 파랑 저항성을 상승시킬 필요성이 있다. 이러한 목적을 위하여 본 연구에서는 동슬래그 및 자철석을 골재로 사용한 중량 콘크리트를 개발하고 이의 염해저항성을 평가하였다. 연구 결과에 따르면, 일반 골재와 중량골재를 각각 혼입한 콘크리트의 28일 압축강도는 큰 차이가 발생하지 않았으나, ASTM C1202에 의한 염소이온침투저항성 시험 시 자철석을 혼입한 콘크리트는 과도한 전류의 흐름으로 평가가 불가능한 것으로 나타났다. 그러나 염소이온의 침투깊이를 이용하는 NT Build 492 시험에서는 ASTM C 1202 시험법에서 관찰된 문제점 없이 실험 진행이 가능하였고, 동슬래그, 자철석을 골재로 사용한 중량 콘크리트의 염소이온침투저항성이 가장 우수한 것으로 나타났다. 따라서 동슬래그 및 자철석을 골재로 사용한 중량콘크리트는 회파블록에 적용이 가능할 것으로 판단된다.

Keywords

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