Tunnel and Underground Space (터널과지하공간)

Korean Society for Rock Mechanics and Rock Engineering (한국암반공학회)
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Sensitivity Analyses of Three-Dimensional Discrete Fracture Network Modeling of Rock Mass

암반의 3차원 불연속균열망(DFN)에 관한 연구 및 민감도분석

  • 박정찬 (인하대학교 에너지자원공학과) ;
  • 박승훈 (인하대학교 에너지자원공학과) ;
  • 김하영 (인하대학교 에너지자원공학과) ;
  • 김건영 (한국원자력연구원) ;
  • 권상기 (인하대학교 에너지자원공학과)
  • Received : 2015.06.16
  • Accepted : 2015.08.11
  • Published : 2015.08.31
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Abstract

This study analyzes the relationship between parameters of the discontinuity in Discrete Fracture Network model such as fracture intensity, fracture orientation, fracture size, fracture shape etc. In this paper, FracMan code was used to model and analyze 3D DFN. A sensitivity analysis was performed in order to analyze the relationship between linear fracture intensity measure ($P_{10}$) and parameters of the discontinuity in $100m{\times}100m{\times}100m$ model area. As a result the sensitivity analysis showed that key parameters affecting fracture intensity are fracture orientation (Trend / Plunge). Conversion factor($C_{13}$) for $P_{10}$, to calculate volumetric fracture intensity measure ($P_{32}$), is derived in case of vertical well and horizontal well when trend is $10^{\circ}$, $30^{\circ}$, $60^{\circ}$, $90^{\circ}$, $120^{\circ}$, $150^{\circ}$, $180^{\circ}$ (7cases) and plunge is $5^{\circ}$, $15^{\circ}$, $30^{\circ}$, $45^{\circ}$, $60^{\circ}$, $75^{\circ}$, $85^{\circ}$ (7cases). It is expected that this paper can be used effectively for modeling and understanding DFN model.

본 연구에서는 불연속암반의 모사기법인 3차원 불연속균열망(Discrete Fracture Network, DFN)모델의 구성 및 해석 코드인 FracMan을 이용하여, DFN모델에서의 불연속면의 밀도(fracture intensity), 불연속면의 방향성(fracture orientation), 불연속면의 크기(fracture size), 불연속면의 모양(fracture shape) 등의 불연속면의 특성인자간의 관계를 분석하고자 하였다. $100m{\times}100m{\times}100m$ 모델영역에서 균열의 선형밀도($P_{10}$)와 불연속면을 구성하는 인자 간의 상관관계 분석을 위해 민감도 분석을 수행하였다. 본 연구 결과, 불연속면의 밀도에 가장 큰 영향을 미치는 인자로는 불연속면의 방향성 인자인 선주향(Trend)과 선경사(Plunge)로 나타났다. 불연속면의 체적밀도($P_{32}$)의 계산을 위해서 불연속면의 선주향이 $10^{\circ}$, $30^{\circ}$, $60^{\circ}$, $90^{\circ}$, $120^{\circ}$, $150^{\circ}$, $180^{\circ}$인 7가지 경우와 선경사가 $5^{\circ}$, $15^{\circ}$, $30^{\circ}$, $45^{\circ}$, $60^{\circ}$, $75^{\circ}$, $85^{\circ}$인 7가지 경우에서의 수직, 수평시추일 경우에 관한 $P_{10}$의 환산인자($C_{13}$)를 도출하였다. 본 연구의 결과가 불연속균열망 모델을 구성하고 이해하는 데 효과적으로 사용될 수 있을 것이다.

Keywords

References

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