Tunnel and Underground Space (터널과지하공간)

Korean Society for Rock Mechanics and Rock Engineering (한국암반공학회)
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Hydraulic Analysis of a Discontinuous Rock Mass Using Smeared Fracture Model and DFN Model

DFN 모델과 스미어드 균열 모델을 이용한 불연속 암반의 3차원 수리해석

  • Received : 2019.09.18
  • Accepted : 2019.10.09
  • Published : 2019.10.31
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Abstract

A three-dimensional(3D) equivalent continuum modeling was performed to analyze hydraulic behavior of rock mass considering discontinuities by using DFN model and smeared fracture model. DFN model was generated by FLAC3D and smeared fracture model was applied by using FISH functions, which is built-in functions in FLAC3D, for equivalent continuum model of fractured rock mass. Comparative analysis with 3DEC, which is for discontinuum analysis, was conducted to verify reliability of equivalent continuum analysis by using FLAC3D. Similar results of hydraulic analysis under the same conditions could be achieved. Equivalent continuum analysis of fractured rock mass by using DFN model was implemented to compare with existing analytical methods for inflow into the tunnel.

본 연구에서는 3차원 불연속균열망을 이용하여 불연속 암반을 모사하여 스미어드 균열 모델을 적용한 불연속 암반의 등가연속체 해석기법에 대해 연구를 실시했다. 연속체 해석 코드인 FLAC3D를 이용하여 모델링을 수행하였고, 해당 적용 모델의 신뢰성을 검증하기 위해 불연속체 해석에 널리 사용되는 3DEC 코드를 통해 모델의 메쉬 사이즈, 불연속면의 밀도 및 불연속면의 간극에 대한 민감도 분석을 함께 실시하여 제안 모델의 신뢰성을 검증할 수 있었다. 본 논문에서 제안된 등가연속체 해석기법을 이용한 불연속 암반의 수리해석에 대한 연구결과는 교통 터널, 석유비축기지, 방사성폐기물 처분장 등의 지하 구조물 설계 및 건설 분야에 기초자료로 활용될 것이라고 판단된다.

Keywords

References

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