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Hydration of High-volume GGBFS Cement with Anhydrite and Sodium Sulfate

경석고 및 황산나트륨을 함유한 하이볼륨 고로슬래그 시멘트의 수화특성

  • Moon, Gyu-Don (High-tech Construction Materials Center, Korea Conformity laboratories) ;
  • Choi, Young-Cheol (High-tech Construction Materials Center, Korea Conformity laboratories)
  • 문규돈 (한국건설생활환경시험연구원 첨단건설재료센터) ;
  • 최영철 (한국건설생활환경시험연구원 첨단건설재료센터)
  • Received : 2014.10.28
  • Accepted : 2014.12.16
  • Published : 2015.04.30

Abstract

In order to use the high-volume slag cement as a construction materials, a proper activator which can improve the latent hydraulic reactivity is required. The dissolved aluminum silicon ions from ground granulated blast furnace slag (GGBFS) react with sulfate ions to form ettringite. The proper formation of ettringite can increase the early-age strength of high-volume GGBFS (80%) cement. The aim of this study is to investigate the hydration properties with sulfate activators (sodium sulfate, anhydrite). In this paper, the effects of $Na_2SO_4$ and $CaSO_4$ on setting, compressive strength, hydration, micro-structure were investigated in high-volume GGBFS cement and compared with those of without activator. Test results indicate that equivalent $SO_3$ content of 3~5% improve the early-age hydration properties such as compressive strength, heat evolution rate, micro-pore structure in high-volume GGBFS cement.

시멘트를 대체하여 고로슬래그 미분말을 건설재료로 대량으로 활용하기 위해서는 잠재수경성을 향상시켜 조기강도를 개선시킬 수 있는 적절한 활성화제가 필요하다. 이 연구에서는 경석고와 황산나트륨을 이용하여 하이볼륨 고로슬래그 시멘트의 수화특성에 대한 연구를 수행하였다. 수화특성을 평가하기 위해 고로슬래그 미분말을 전체 바인더의 80%로 고정하였으며, 나머지 20%를 시멘트와 활성화제로 구성하였다. 경석고와 황산나트륨의 치환율(1~7%)에 따른 응결, 압축강도, 미소수화열 및 미세구조 특성을 시멘트만을 사용한 경우와 비교하여 분석하였다. 이 연구에서는 경석고와 황산나트륨을 활성화제로 사용한 경우, 하이볼륨 고로슬래그 미분말의 조기 수화특성을 향상을 위해 필요한 $SO_3$ 함량을 전체 바인더 중량대비 약 3~5% 제안하였다.

Keywords

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