Journal of the Korea Institute of Building Construction (한국건축시공학회지)

The Korean Institute of Building Construction (한국건축시공학회)
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Properties of the Alkali Activated Mortar According to Metakaolin Replacement Ratio

알칼리 활성화 모르타르의 메타카올린 치환율에 따른 특성

  • Received : 2016.05.21
  • Accepted : 2016.07.19
  • Published : 2016.08.20
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Abstract

The aim of this study is to look into the metakaolin replacement ratio of blast furnace slag based alkali activated slag mortar and its mechanical characteristics according to changes in stimulant concentration. Metakaolin has high fineness, and therefore the fluidity becomes lower as the replacement ratio becomes higher. So in this study, a sufficient value of mixing water was provided to secure fluidity for the characteristic experiment, and a different W/B was derived for each specimen in order to make the fluidity identical. A characteristic experiment was conducted according to the mol concentration of NaOH, which was used as the mixing water that affects fluidity. Additionally, compressive strength measurement, observation of inner microstructure through SEM, acid resistance experiment, and neutralization resistance was conducted. The results of this study revealed that for a high concentration NaOH solution to have even fluidity, a high W/B is necessary, and the functions were enhanced, not degraded.

본 연구의 목적은 고로슬래그 베이스 AAS 모르타르의 메타카올린 치환율과 자극제 농도의 변화에 따른 역학적 특성과 내구성에 대하여 알아보는 것이다. 메타카올린은 분말도가 높아서 치환율이 높아질수록 유동성이 많이 저하되기 때문에 본 연구에서는 충분한 NaOH 수용액를 가하여 시공성을 확보한 상태에 실험을 진행하였다. 따라서 모든 시험체의 시공성을 동일하게 하는 각기 다른 Ws/B를 도출하였고, 이에 따라 시공성에 영향을 미치는 NaOH 수용액의 몰 농도별 특성에 대한 실험을 진행하였다. 또한 압축강도 측정실험, SEM을 통한 내부 미세구조 관찰, 내산성 실험 실험을 진행하였다. 본 연구 결과 메타카올린 치환율이 높은 배합은 Ww가 많이 필요로 하였지만, 그에 따른 성능 저하는 나타나지 않으며 오히려 우수한 역학적 내구적 성능을 보여주었다. 또한 [6M]보다 [8M]농도의 NaOH 자극제를 사용했을 때 메타카올린 치환 효과가 극대화 되었다.

Keywords

References

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