Journal of the Korean Recycled Construction Resources Institute (한국건설순환자원학회논문집)

Korean Recycled Construction Resources Institute (한국건설순환자원학회)
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Mechanical Properties of PHC Pile Concrete using Alpha-type Hemihydrate Gypsum

알파형 반수석고를 활용한 PHC 파일 콘크리트의 역학적 특성

  • Hong-Seop Kim (Department of Building Research, Korea Institute of Civil Engineering and Building Technology) ;
  • Kyoung-Su Shin (Jayeon Structure Engineering Company) ;
  • Do-Gyeum Kim (Department of Structural Engineering Research, Korea Institute of Civil Engineering and Building Technology)
  • 김홍섭 (한국건설기술연구원 건축연구본부) ;
  • 신경수 ((주)자연구조엔지니어링 기업부설연구소) ;
  • 김도겸 (한국건설기술연구원 구조연구본부)
  • Received : 2023.12.15
  • Accepted : 2024.01.10
  • Published : 2024.03.30
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Abstract

In this study, the mechanical properties of PHC pile concrete using alpha-type hemihydrate gypsum were evaluated. As the replacement ratio of alpha-type hemihydrate gypsum increased, the setting time rapidly accelerated. In particular, when replacement ratio exceeded 20 %, the setting time was shortened due to rapid hydration reaction, making it impossible to secure working time. As the replacement ratio of alpha-type hemihydrate gypsum increased, the ettringite and gypsum peaks tended to increase, and it is believed that the shrinkage of concrete decreased due to the increase in the ettringite peak. At a As the replacement ratio of 5 to 15 % for alpha-type hemihydrate gypsum, the compressive strength increased or was found to be equivalent to that of OPC. But at 20 % substitution, workability deteriorated due to rapid setting, so use of the 5 to 15 % range is considered appropriate.

본 연구에서는 알파형 반수석고를 활용한 PHC 파일 콘크리트의 역학적 특성을 평가하였다. 알파형 반수석고의 치환율이 증가할수록 응결시간이 급격히 빨라졌으며, 특히 20 % 이상 치환 시 급격한 수화반응으로 응결시간이 단축되어 작업 시간 확보가 불가능하였다. 알파형 반수석고의 치환율이 증가할수록 ettringite와 Gypsum 피크가 증가하는 경향을 보였으며, ettringite 피크 증가로 인해 콘크리트의 수축량이 감소하는 것으로 판단된다. 알파형 반수석고 치환율 5~15 %에서는 OPC 대비 압축강도가 증가하거나 동등 수준으로 나타났으나 20 % 치환 시 급격한 응결로 인한 작업성이 저하되어 5~15 % 범위의 사용이 적절하다고 판단된다.

Keywords

Acknowledgement

본 연구는 과학기술정보통신부 한국건설기술연구원 연구운영비지원(적립금사업)사업으로 수행되었습니다(과제번호 20230404-001, 카자흐스탄의 산업폐기물 활용을 위한 국제공동기초연구).

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