대한토목학회논문집 (KSCE Journal of Civil and Environmental Engineering Research)

  • 제41권4호
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  • Pages.341-345
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  • 2021
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  • 1015-6348(pISSN)
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  • 2799-9629(eISSN)
대한토목학회 (Korean Society of Civil Engeneers)
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해수에 노출된 슬래그 시멘트의 장기 상변이 열역학 모델링

Thermodynamic Modeling of Long-Term Phase Development of Slag Cement in Seawater

  • 박솔뫼 (부경대학교 토목공학과) ;
  • 서용철 (부경대학교 토목공학과) ;
  • 남광희 (부경대학교 산학협력단) ;
  • 원윤상 (부경대학교 산학협력단)
  • 투고 : 2020.09.10
  • 심사 : 2021.01.21
  • 발행 : 2021.08.01
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⟨ 이전 논문 다음 논문 ⟩

초록

고로슬래그는 콘크리트의 염소이온침투 저항성능 개선 목적으로 가장 널리 활용되는 혼화재이나, 해수에 노출된 고로슬래그 혼입 콘크리트의 장기거동 및 상변이에 대한 보고는 부족한 실정이다. 본 연구에서는 열역학 모델링을 통해 해수에 노출된 슬래그 시멘트의 장기 상변이를 모사하였다. 모델링 결과 슬래그 혼입은 해수에 노출되었을 때 상변이가 쉽게 일어나지 않는 안정적인 상을 생성시킬 것으로 예측되었다. 해수에 노출되었을 때 ettringite 생성으로 인해 포틀랜드 시멘트 및 슬래그 시멘트에서 모두 팽창이 일어날 것으로 예측되었으나, 슬래그 시멘트에서는 brucite가 덜 생기는 것을 확인하였다. 공극률은 슬래그 혼입 시멘트의 경우 더 높았으나, 염소 흡착능이 높은 알루미네이트 수화물이 슬래그 시멘트에서 더 활발히 생성되는 것을 확인하였다. 따라서 슬래그 혼입을 통해 해양 환경에서 사용되는 콘크리트의 내구성능을 크게 증진시킬 수 있는 것으로 나타났다.

Known to improve resistance to chloride ingress, blast furnace slag is a widely used supplementary cementitious material. However, a detailed characterization of cements blended with slag exposed to seawater remains unavailable. This study employs thermodynamic modeling as a toolkit for assessing the long-term phase evolution of slag cement in seawater. The modeling result shows that slag incorporation leads to the formation of phases that are less prone to structural alteration in seawater. Formation of more ettringite is expected to induce expansion in both plain and blended cements, while brucite is unstable in the blended systems. Despite this, the porosity is expected to increase in the blended cements, and aluminate hydrates with a higher chloride binding capacity are more abundant in the blended cements. The results suggest that the use of slag in concrete improves the durability performance of concrete in marine environments.

키워드

과제정보

This study was supported by the Pukyong National University Development Project Research Fund 2020, and by National Research Foundation of Korea (Grant No. 2018R1D1A1B07047233).

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