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

Korea Institute for Structural Maintenance Inspection (한국구조물진단유지관리공학회)
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Investigation of the Effects of CNT Dosages on the Hydration and Heating Properties of Cement Composites with Low Water-to-binder Ratio

낮은 물-바인더 비를 갖는 시멘트 복합체의 CNT 첨가량에 따른 수화특성 및 발열특성

  • 오성우 ((재)한국건설생활환경시험연구원 건설기술연구센터) ;
  • 정상화 ((재)한국건설생활환경시험연구원 건설기술연구센터) ;
  • 정원석 (경희대학교 토목공학과) ;
  • 최영철 (가천대학교 토목환경공학과)
  • Received : 2018.10.10
  • Accepted : 2018.10.25
  • Published : 2018.11.01
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Abstract

Recently, various researches on the utilization of carbon nanotube(CNT) with superior electrical conductivity and large surface areas into concrete have been actively conducted. Thus, mechanical and thermal properties of cement-flyash composites were evaluated concerning the CNT replacements. Based on the low binder-to-water ratio, the cement composites were produced with 0.2 % and 0.5 % of CNT solids. The compressive strengths with various ages, isothermal calorimetry measurement, SEM analysis, thermal conductivity of cement composites and thermal gravimetry analysis were implemented. As the amount of CNT addition was increased, the thermal conductivity of cement composites were also increased. Also, there was no significant mechanical property differences between mixtures with and without CNTs.

최근 우수한 전기전도도와 넓은 비표면적을 갖는 탄소나노튜브(CNT)를 활용하여 고강도 및 고내구성 콘크리트의 생산을 위한 연구가 많은 연구자들에 의하여 활발히 이루어지고 있다. CNT의 혼입을 통한 콘크리트의 고강도에 대한 연구가 주를 이루고 있으나, 그 외의 연구는 미흡한 실정이다. 이에, 본 연구에서는 CNT 첨가량에 대한 시멘트 복합체의 역학성능 및 발열성능에 대한 평가를 실시하였다. 낮은 물-바인더 비를 기반으로 하는 시멘트-플라이애시 배합에 대하여, 바인더 중량대비 0.2% 및 0.5%의 CNT 첨가에 따른 재령별 압축강도, 수화특성분석을 위한 미소수화열 분석, 페이스트 내 CNT의 분산 및 주변 수화물과의 관계를 규명하기 위한 SEM분석, 기준전극 삽입을 통한 발열실험 및 열 중량 분석을 실시하였다. CNT 첨가량의 증가에 따라 발열성능은 증가하며, CNT가 첨가되지 않은 기준 배합 CNT가 첨가된 배합의 경우 동등수준의 역학성능을 갖는 것으로 나타났다.

Keywords

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