Tunnel and Underground Space (터널과지하공간)

Korean Society for Rock Mechanics and Rock Engineering (한국암반공학회)
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Review of Numerical Approaches to Simulate Time Evolution of Excavation-Induced Permeability in Argillaceous Rocks

점토질 퇴적암 내 굴착영향영역 투수특성의 시간경과 변화 파악을 위한 수치해석기법에 대한 고찰

  • Kim, Hyung-Mok (Department of Energy Resources and Geosystems Engineering, Sejong University) ;
  • Park, Eui-Seob (Deep Subsurface Research Center, Korea Institute of Geoscience and Mineral Resources)
  • 김형목 (세종대학교 지구자원시스템공학과) ;
  • 박의섭 (한국지질자원연구원 지질환경연구본부)
  • Received : 2020.12.14
  • Accepted : 2020.12.23
  • Published : 2020.12.31
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Abstract

We reviewed numerical approaches to assess a hydraulic properties of excavation-disturbed zone (EDZ)created in argillaceous sedimentary rocks. It has been reported that fractures in the sedimentary rocks containing expansive clays are gradually closing due to swelling and their permeabilities are evolving to the level of in-tact rock, which is known as a self-healing or self-sealing process. The numerical approaches introduced here are capable of simulating spatio-temporal variation of EDZ permeability during long-term operation of a repository by including the self-healing characteristics of fractures, which wa observed in laboratory as well as in-situ experiments, The applicability of the numerical approaches was verified from the comparison to in-situ measurements of EDZ permeability at underground research laboratories.

본 고에서는 점토질 퇴적암 부지에 건설되는 처분갱도 주변 굴착영향영역에서의 투수특성을 평가하기 위한 수치해석기법을 검토하였다. 팽창성 점토를 함유한 퇴적암에 형성된 굴착영향영역 내 균열은 포화과정에서 점진적으로 간극을 상실하고 주변 모암의 투수계수에 수렴해 가는 자기 치유(self-healing) 혹은 자기 밀봉(self-sealing) 특성을 보이는 것으로 알려져 있다. 본고에 소개된 수치해석기법은 실내 및 현장실험을 통해 관측된 균열의 자기 치유 거동을 고려함으로써 처분장 건설 후 장기 운영과정에서 예상되는 굴착영향영역 투수계수의 시공간적 변화를 파악할 수 있는 특징이 있다. 지하연구시설 내 굴착 갱도 주변에서 현장투수시험을 통해 획득한 투수계수 측정치와 수치해석에 의한 결과를 비교 분석함으로서 활용타당성을 검증하였다.

Keywords

Acknowledgement

한국지질자원연구원 2020년 주요사업의 일환으로 수행되었으며, 제1저자는 과학기술정보통신부의 재원으로 수행되는 한국연구재단의 기초연구사업(2019R1F1A1058711)의 지원을 받았습니다. 지원에 감사드립니다.

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