Journal of the Korean Recycled Construction Resources Institute (한국건설순환자원학회논문집)

Korean Recycled Construction Resources Institute (한국건설순환자원학회)
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Experimental Study on the Gas Permeability of Nuclear Power Plant Concrete with Construction Joints

시공이음 생성에 따른 원전 콘크리트의 기체투기성에 대한 실험적 연구

  • Eun-A Seo (Department of Structural Engineering Research, Korea Institute of Civil engineering and Building Technology) ;
  • Do-Gyeum Kim (Department of Structural Engineering Research, Korea Institute of Civil engineering and Building Technology) ;
  • Ho-Jae Lee (Department of Structural Engineering Research, Korea Institute of Civil engineering and Building Technology)
  • 서은아 (한국건설기술연구원 구조연구본부) ;
  • 김도겸 (한국건설기술연구원 구조연구본부) ;
  • 이호재 (한국건설기술연구원 구조연구본부)
  • Received : 2024.07.26
  • Accepted : 2024.08.07
  • Published : 2024.09.30
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Abstract

In this study, the gas permeability characteristics according to the construction joint were evaluated under pressure conditions ranging from 0 to 300 psi. The pore distribution and pore ratio were analyzed using X-ray CT. The average porosity of the OPC specimen was 0.74 %, while the FA specimen showed a relatively low pore ratio of 0.51 to 0.65 % regardless of the presence of the construction joint. For the OPC and FA plain specimens with a thickness of 50 mm without construction joints, no gas permeation occurred below 300 psi. At 300 psi, the gas permeation rates of the specimens with rough and smooth construction joint surfaces were 0.28 L/min and 0.31 L/min, respectively, which were 1.7 times higher than those of the specimens without construction joints. This is because the construction joints affected the distribution of the pores and coarse aggregates and the penetration path within the concrete. The porosity in the construction joint was the highest at about 2 %, and it was confirmed that the pore ratio gradually increased as it approached the joint.

이 연구에서는 0~300 psi의 압력조건에서 콘크리트의 시공이음 생성에 따른 기체 투기특성을 평가하였으며, X-ray CT를 통하여 공극분포와 공극률을 분석하였다. OPC 시험체의 평균 공극률은 0.74 %이며, FA 시험체는 시공이음 여부와 관계없이 0.51~0.65 %로 상대적으로 낮은 공극률을 나타내었다. 시험체 두께가 50 mm일 때. 일체 타설로 제작한 OPC와 FA 시험체는 300 psi 미만에서 기체가 투기되지 않았다. 300 psi에서 FA 배합으로 시공이음면을 거칠게 제작한 시험체와 시공이음면을 가공하지 않은 시험체의 투기량은 각각 0.28 L/min과 0.31 L/min로 일체타설 시험체 대비 1.7배 이상 높았다. 이는 시공이음이 콘크리트 내부의 공극과 굵은골재의 분포 및 투기경로에 영향을 주었기 때문으로 판단된다. 시공이음부의 공극률은 2 % 내외로 가장 높았으며, 시공이음부에 가까워질수록 공극률이 점점 높아지는 것을 확인하였다.

Keywords

Acknowledgement

이 연구는 정부(과학기술정보통신부)의 재원으로 한국연구재단의 지원을 받아 수행된 연구임(No. RS-2022-00143120).

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