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An Experimental Study on Relation between Chloride Diffusivity and Microstructural Characteristics for GGBS Concrete

슬래그 미분말 혼합 콘크리트의 공극구조와 염화물 확산계수와의 관계에 대한 실험적 연구

  • Kim, Tae-Sang (Construction Material Research Center, Korea Institute of Construction Materials) ;
  • Jung, Sang-Hwa (Construction Material Research Center, Korea Institute of Construction Materials) ;
  • Choi, Young-Cheol (Construction Material Research Center, Korea Institute of Construction Materials) ;
  • Song, Ha-Won (Dept. of Civil and Environmental Engineering, Yonsei University)
  • 김태상 (한국건자재시험연구원 건설기반기술센터) ;
  • 정상화 (한국건자재시험연구원 건설기반기술센터) ;
  • 최영철 (한국건자재시험연구원 건설기반기술센터) ;
  • 송하원 (연세대학교 사회환경시스템공학부)
  • Published : 2009.10.31

Abstract

In order to evaluate the durability of reinforced concrete structures under chloride attack from sea water and frost damage, it is important to analyze both the microstructural characteristics of concrete and its diffusion resistance of concrete against chloride ingress. In this study, a relation between micro-pore structures of concrete obtained by the Mercury Intrusion Porosimetry and accelerated chloride diffusivity as well as long term chloride diffusivity were studied for ground granulated blast furnace slag(GGBS) concrete. Different water-cement ratio of 40, 45, 50% and different unit cement concrete of 300, 350, 400 or 450 kg/$m^3$ of the GGBS concrete along with OPC concrete were used and freeze and thawing, and the change in diffusivity and microstructure were observed for both GGBS concrete and damaged GGBS concrete due to rapid freezing and thawing.

바닷물에 의한 염해와 동결융해 환경에 노출된 철근 콘크리트구조물의 내구성을 평가하기 위해서는 콘크리트의 미세구조적 특성 및 염화물 침투성에 대한 콘크리트의 확산 저항성을 동시에 분석하는 것이 중요하다. 이 연구에서는 고로슬래그 미분말(GGBS)을 혼합한 콘크리트에 대하여 수은압입법(MIP)에 의해 얻어진 콘크리트의 미세공극 구조와 장기 및 단기 재령의 염화물 확산성과의 상관성에 대하여 연구하였다. 물시멘트비는 40, 45, 50%로 변화시키고, 단위시멘트량을 300, 350, 400, 450 kg/$m^3$으로 변화시킨 OPC 및 GGBS 콘크리트 시편에 대하여 동결융해에 의해 손상된 GGBS 콘크리트에서의 확산성과 미세구조의 변화를 관찰하였다.

Keywords

References

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