Tunnel and Underground Space (터널과지하공간)

Korean Society for Rock Mechanics and Rock Engineering (한국암반공학회)
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Fault Reactivation Modeling Using Coupled TOUGH2 and FLAC3D Interface Model: DECOVALEX-2019 Task B

TOUGH2-FLAC3D Interface 모델을 통한 단층 재활성 모델링: DECOVALEX-2019 Task B

  • Park, Jung-Wook (Geologic Environment Division, Korea Institute of Geoscience of Mineral Resources) ;
  • Park, Eui-Seob (Geologic Environment Division, Korea Institute of Geoscience of Mineral Resources) ;
  • Lee, Changsoo (Radioactive Waste Disposal Research Division, Korea Atomic Energy Research Institute)
  • 박정욱 (한국지질자원연구원 지질환경연구본부) ;
  • 박의섭 (한국지질자원연구원 지질환경연구본부) ;
  • 이창수 (한국원자력연구원 방사성폐기물처분연구부)
  • Received : 2020.08.13
  • Accepted : 2020.08.26
  • Published : 2020.08.31
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Abstract

We present a numerical model to simulate coupled hydro-mechanical behavior of fault using TOUGH-FLAC simulator. This study aims to develop a numerical method to estimate fluid injection-induced fault reactivation in low permeability rock and to access the relevant hydro-mechanical stability in rock as part of DECOVALEX-2019 Task B. A coupled fluid flow and mechanical interface model to explicitly represent a fault was suggested and validated from the applications to benchmark simulations and the field experiment at Mont Terri underground laboratory in Switzerland. The pressure build-up, hydraulic aperture evolution, displacement, and stress responses matched those obtained at the site, which indicates the capability of the model to appropriately capture the hydro-mechanical processes in rock fault.

본 연구에서는 TOUGH-FLAC 연동해석기법을 통해 단층의 수리역학적 거동을 평가할 수 있는 수치해석 모델을 제안하였다. 이는 국제공동연구 DECOVALEX-2019 Task B의 일환으로 수행되었으며, 불투수성 암반 내 유체 주입으로 인한 단층의 재활성을 예측하고 주변 암반의 수리역학적 안정성을 평가할 수 있는 해석모델을 개발하는 데에 그 목적이 있다. 본 연구에서는 TOUGH2 수리유동모델과 FLAC3D의 역학적 인터페이스 모델의 연동을 통해 단층의 역학적 거동을 보다 합리적으로 구현할 수 있는 해석기법을 제안하고, 벤치마크 해석과 스위스 Mont Terri 지하연구시설 현장시험에 적용하여 그 타당성과 유효성을 검증하였다. 개발된 해석 모델은 유체의 주입으로 인한 단층 내 압력 분포의 발달, 역학적 변형에 따른 수리간극의 변화, 변위와 응력 등 단층의 수리역학적 거동을 적절히 재현할 수 있는 것으로 나타났다.

Keywords

References

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