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Effect of Types of Accelerators and Replacement Levels of GGBFS on the Performance of Shotcrete Mortars

숏크리트 모르타르의 성능에 대한 급결제 종류 및 고로슬래그 미분말 대체율의 영향

  • 이승태 (군산대학교 토목공학과) ;
  • 김성수 (대진대학교 건설시스템공학과) ;
  • 김동규 (한국건설기술연구원 Geo 인프라연구실) ;
  • 박광필 (한국건설기술연구원 Geo 인프라연구실)
  • Received : 2012.07.06
  • Accepted : 2012.11.26
  • Published : 2013.01.30

Abstract

In this study, some engineering properties of OPC and GGBFS shotcrete mortars with alkali-free or aluminate accelerator were experimentally examined. As a result, GGBFS mortars with alkali-free accelerator were significantly similar to OPC mortars with same accelerator with respect to both setting time and compressive strength. Comparatively, GGBFS mortars with aluminate accelerator showed a good performance with an increased replacement of GGBFS. Furthermore, when replaced with GGBFS over 50%, the mortars exhibited superior performances of electrical resistivity and chloride ions penetration resistance. Accordingly, it is suggested that GGBFS has a beneficial effect as shotcreting materials in the condition of proper replacement levels.

본 연구에서는 alkali-free 및 aluminate 급결제를 사용한 OPC 및 GGBFS 숏크리트 모르타르의 응결특성, 강도특성, 전기저항성 및 염소이온 침투저항성을 실험적으로 고찰하였다. 실험결과에 따르면, alkali-free 급결제를 첨가한 GGBFS 모르타르는 응결시간 및 압축강도가 GGBFS 대체율에 관계없이 OPC 모르타르와 유사하게 나타났으나, aluminate 급결제를 첨가한 모르타르의 경우, GGBFS 대체율이 증가할수록 응결시간 및 압축강도가 크게 나타나는 경향을 보였다. 한편, 숏크리트 모르타르의 전기저항성 및 염소이온 침투저항성은 GGBFS를 50% 이상 대체한 모르타르가 우수한 경향을 나타내므로써, 적절한 대체율의 GGBFS를 사용한 모르타르가 숏크리트용 재료로써 우수한 성능을 나타낼 것으로 판단된다.

Keywords

References

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