Journal of the Korea institute for structural maintenance and inspection (한국구조물진단유지관리공학회 논문집)

Korea Institute for Structural Maintenance Inspection (한국구조물진단유지관리공학회)
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The Strength and Drying Shrinkage Properties of Alkali-activated Slag using Hard-burned MgO

MgO를 혼합한 알칼리 활성화 슬래그의 강도와 건조수축 특성

  • 김태완 (부산대학교 생산기술연구소) ;
  • 전유빈 (울산과학기술대학교 도시환경공학부)
  • Received : 2015.03.20
  • Accepted : 2015.05.07
  • Published : 2015.05.30
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Abstract

In this study, the properties of strength and drying shrinkage of alkali-activated slag cement (AASC) with magnesium oxide (MgO) contents between 0 and 16 wt% were investigated. The ground granulated furnace blast slag (GGBFS) was activated by potassium hydroxide (KOH) and dosage of activator was 2M and 4M. The MgO was replaced with 2% to 16% of GGBFS by weight. The water-binder ratio (w/b) was 0.5. In the result, the higher MgO content leads to a slightly higher degree of reaction and thus to a higher compressive strength at all ages. The compressive strength and ultra sonic velocity (UPV) increased with increases MgO contents. The drying shrinkage of AASC was decreased as the contents of MgO increases. The results from SEM confirmed that there were densified reaction product of higher MgO content specimens.

본 연구는 MgO를 0~16% 사용한 알칼리 활성화 슬래그 시멘트 (AASC)의 강도와 건조수축 특성에 관안 연구이다. 고로슬래그 미분말 (GGBFS)는 KOH를 활성화제로 사용하였고, 활성화제의 농도는 2M과 4M이다. MgO는 GGBFS의 중량에 대해 치환하였고 물-결합재 비 (w/b)는 0.5이다. 실험결과, 높은 MgO 치환율은 높은 수화반응으로 모든 재령에서 높은 압축강도를 나타내었다. 압축강도와 초음파속도 (UPV)는 MgO의 양이 증가함에 따라 증가되었다. AASC의 건조수축은 MgO의 양이 증가함에 따라 감소하였다. SEM 결과를 통해 높은 양의 MgO 시험체는 치밀한 반응 생성물질이 만들어 진 것을 확인할 수 있다.

Keywords

References

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