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

Korea Institute for Structural Maintenance Inspection (한국구조물진단유지관리공학회)
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Hydration and Compressive Strength of High-volume Fly Ash Cement Paste

하이볼륨 플라이애시 시멘트 페이스트의 수화 및 압축강도 특성

  • 황철성 (가천대학교 토목환경공학과) ;
  • 문은진 (한국건설생활환경시험연구원)
  • Received : 2017.07.28
  • Accepted : 2017.08.14
  • Published : 2017.09.01
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Abstract

Recently, researches on High-Volume Fly ash Cement(HVFC), which is replacing high portion of cement to fly ash, have been actively conducted to reduce $CO_2$ formation. Though HVFC has various advantages, low strength development in early ages is pointed out as the biggest problem in the application of fly ash. In order to overcome such limitations, this study investigated the hydration and compressive strength characteristics of HVFC paste depending on the fly ash content with the mixing ratio varying from 0 to 80 %. Experimental results show that the HVFC paste with low water-binder ratio can overcome the limitation of low compressive strength at early ages. Also, from the result of heat flow delay, 50 % of fly ash weight ratio was the critical point of the filler effect.

국내 시멘트 산업은 시멘트 제조 시 발생되는 $CO_2$를 감축하기 위해 $CO_2$발생의 주요 요인인 클링커 대신 시멘트 대체재료 사용을 확대하기 위한 다양한 기술 개발을 위해 노력하고 있다. 이에, 최근 플라이애시를 다량 치환한 하이볼륨 플라이애시 시멘트(HVFC)에 대한 연구 가 활발히 진행되고 있다. 하지만, 플라이애시의 다양한 장점에도 불구하고 낮은 조기강도 발현 특성이 플라이애시를 다량으로 활용한 바인더의 현장적용에 있어서 가장 큰 문제로 지적되고 있다. 본 연구는 이러한 한계를 극복하고자 플라이애시 혼입률에 따른 HVFC 페이스트의 수화 및 압축강도 특성을 파악하기 위해, 플라이애시 혼입률 0~80%의 배합을 이용하여 실험을 수행하였다. 실험결과 낮은 물-바인더 비에 의한 HVFC 페이스트 배합은 초기 재령에서의 낮은 압축강도의 한계점을 극복할 수 있을 것으로 판단된다. 또한 중량비의 50% 이상이 플라이애시로 치환된 페이스트의 응결시간이 증가하는 경향을 보아, 플라이애시 중량비 50%는 충진 효과의 임계점으로 판단된다.

Keywords

References

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