콘크리트학회논문집 (Journal of the Korea Concrete Institute)

  • 제27권4호
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  • Pages.435-441
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  • 2015
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  • 1229-5515(pISSN)
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  • 2234-2842(eISSN)
한국콘크리트학회 (Korea Concrete Institute)
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콜드조인트를 가진 OPC 및 GGBFS 콘크리트의 투수성 평가

Permeability Evaluation of OPC and GGBFS Concrete with Cold Joint

  • 최세진 (원광대학교 건축공학과) ;
  • 김성준 (한국건설기술연구원) ;
  • 문진만 (한남대학교 건설시스템 공학과) ;
  • 권성준 (한남대학교 건설시스템 공학과)
  • 투고 : 2015.04.01
  • 심사 : 2015.05.26
  • 발행 : 2015.08.30
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초록

콘크리트는 다공성 매채로 투수성을 가지고 있으며, 투수성은 내구성 평가의 중요한 인자가 된다. 콘크리트는 이어치기의 지연을 통해서 콜드조인트를 가지게 되는데, 이러한 이음은 투수와 유해물질의 유입을 가속화시킨다. 본 연구에서는 고로 슬래그 미분말과 보통포틀랜트 시멘트를 사용하여 콜드조인트 콘크리트를 제조하였으며, 91일 재령 하에서 2주간 투수계수 및 유량을 측정하였다. 고로슬래그 미분말을 혼입한 배합에서는 투수성이 OPC 배합에 비해 0.89배 감소하였으며, 콜드조인트에도 보통배합에 비해 투수계수가 0.86배 감소하였다. 본 연구에서는 저압 투수법을 통하여 콜드조인트 및 혼화재가 투수성에 미치는 영향이 평가되었으며, 확률론적인 방법을 통하여 건전부와 콜드조인트부의 투수 변동성 또한 분석되었다.

Concrete, as a porous media, has permeability and it is considered as a major parameter for durability evaluation. Cold joint caused by delayed placing of concrete accelerates water permeation and intrusion of harmful ions. In the paper, concrete specimens containing GGBFS (Ground Granulated Blast Furnace Slag) and OPC (Ordinary Portland Cement) are prepared with cold joint section, and water permeability and water flow at the age of 91 days are measured for 2 weeks. Sound concrete with GGBFS shows decreased permeability to 89% for sound concrete with OPC and 0.86 of decreasing ratio is evaluated in GGBFS concrete with cold joint. Through WPT (Water Penetration Test), the effects of mineral admixture and cold joint on water permeability are evaluated, and variation in water behavior via cold joint is analyzed through probabilistic method as well.

키워드

참고문헌

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