Journal of the Korea Concrete Institute (콘크리트학회논문집)

Korea Concrete Institute (한국콘크리트학회)
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The Strength Characteristics of Activated Multi-Component Cement with Kaolinite

카올린을 혼합한 활성화된 다성분계 시멘트의 강도 특성

  • Kim, Tae-Wan (Research Institute of Industrial Technology (RIIT), Pusan National University) ;
  • Kim, Im-Gon (Department of Civil Engineering, Pusan National University)
  • 김태완 (부산대학교 생산기술연구소) ;
  • 김임곤 (부산대학교 공과대학 건설융합학부 토목공학전공)
  • Received : 2016.05.18
  • Accepted : 2016.08.25
  • Published : 2016.10.30
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Abstract

The paper presented investigates the effects of kaolinite on strength properties of alkali-activated multi-component cement. The binders of this study was blended of ground granulated blast furnace slag (GGBFS), fly ash (FA), silica fume (SF) and kaolinite (KA). In this study, the specimens of combination of 20%~70% GGBFS, 10%~60% FA, 10% SF (constant ratio) and 10%~50% KA binder were used for strength properties tests. The water/binder ratio was 0.5. The binders (GGBFS + FA + SF + KA) was activated by sodium hydroxide (NaOH) and sodium silicate ($Na_2SiO_3$) was 10% by total binder weight (10% NaOH + 10% $Na_2SiO_3$). The research carried out is on the compressive strength, water absorption, ultrasonic pulse velocity (UPV) and X-ray diffraction (XRD). The compressive strength decreased as the contents of KA increase. One of the major reason for this is the low reactivity of KA compared with other raw materials used as precursors such as GGBFS or FA. The presence of remaining KA indicates that the initially used quantity has not fully reacted during hydration. Moreover, the results have indicated that increased of KA contents decreased UPV under all experimental conditions. The drying shrinkage and water absorption increased as the content of KA increase. Test result clearly showed that the strength development of multi-component blended cement were significantly dependent on the content of KA and GGBFS.

본 연구는 알칼리 활성화된 다성분계 시멘트에서 카올린(kaolinite, KA)의 효과에 다른 강도 특성에 관한 것이다. 연구에는 고로슬래그 미분말(GGBFS), 플라이애시(FA), 실리카 퓸(SF) 그리고 카올린(KA)을 결합재로 사용하였다. 시험체는 20% ~ 70% GGBFS, 10% ~ 60% FA, 10% SF(고정 비율) 그리고 10% ~ 50% KA의 범위로 혼합하였다. 물/결합재 비는 0.5이다. 결합재는 수산화나트륨(NaOH)과 규산나트륨($Na_2SiO_3$)을 전체 결합재(GGBFS + FA + SF + KA) 중량의 10% (10% NaOH + 10% $Na_2SiO_3$)비율로 사용하였다. 실험은 압축강도, 물 흡수율, 초음파 속도, 건조수축과 X-ray diffraction (XRD)를 수행하였다. 압축강도는 KA의 양이 증가할수록 감소하였다. 강도감소의 중요한 원인중 하나는 GGBFS 또는 FA와 비교하여 KA의 낮은 활성화 때문이다. 수화가 진행되는 동안 KA는 완전하게 반응하지 않았다. 또한 KA의 양이 증가할수록 UPV는 모든 시험체에서 감소하였다. 건조수축과 물 흡수율은 KA의 양이 증가함에 따라 증가하였다. 이러한 시험결과를 통해 다성분계 시멘트의 강도 특성은 KA와 GGBFS의 양에 큰 영향을 받는 것을 확인하였다.

Keywords

References

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