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Drying Shrinkage Behaviors of Concrete with Powder Type Shrinkage Reducing Agent and Fly Ash

분말형 수축저감제와 플라이애쉬가 혼입된 콘크리트의 건조수축 거동

  • Min, Kyung-Hwan (Research Institute for Engineering & Technology, Chungcheong University) ;
  • Lee, Dong-Gyu (Research Institute for Engineering & Technology, Chungcheong University) ;
  • Jeong, Yong-Wook (Department of Civil Engineering, Chungcheong University)
  • Received : 2015.04.07
  • Accepted : 2015.05.07
  • Published : 2015.05.31

Abstract

In this study, series of tests were performed for drying shrinkage characteristics of concrete with power type shrinkage reducing agent (SRA) and fly ash as a part of research to reduce drying shrinkage of concrete. Firstly, for the mechanical properties, a target strength was acquired securely. In the unrestraint shrinkage tests, the SRA decreased the drying shrinkage about $200{\mu}{\varepsilon}$. Lastly, in the ring tests, due to the tensile creep effect, the concrete with SRA showed the cracking times as much again as the concrete with ordinary Portland cement only did.

본 연구에서는 콘크리트의 건조수축을 저감하기 위한 연구의 일환으로 분말형 수축저감제와 플라이애쉬를 활용한 콘크리트의 건조수축 특성에 관한 일련의 실험을 수행하였다. 수축저감제와 플라이애쉬로 각각 2% 및 20%씩 시멘트를 대체한 배합에 대해, 강도 실험과 수축실험을 실시하였다. 역학적 특성은 목표 강도를 획득하는 것으로 확인되었고, 비구속 수축실험 결과 수축저감제가 약 $200{\mu}{\varepsilon}$의 건조수축 감소 효과를 발생시키는 것으로 나타났다. 링테스트에서는 수축저감제를 적용한 배합은 인장크리프 효과로 인해 균열 발생시기가 약 2배 정도 증가하였다.

Keywords

References

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