Tunnel and Underground Space (터널과지하공간)

Korean Society for Rock Mechanics and Rock Engineering (한국암반공학회)
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Estimation of Strength and Deformation Modulus of the 3-D DFN System Using the Distinct Element Method

개별요소법을 이용한 삼차원 DFN 시스템의 강도 및 변형계수 추정

  • Ryu, Seongjin (Dept. of Energy Resources Engineering, Pukyong National University) ;
  • Um, Jeong-Gi (Dept. of Energy Resources Engineering, Pukyong National University) ;
  • Park, Jinyong (Dept. of Radioactive Waste Disposal Regulation, Korea Institute of Nuclear Safety)
  • 류성진 (부경대학교 에너지자원공학과) ;
  • 엄정기 (부경대학교 에너지자원공학과) ;
  • 박진용 (한국원자력안전기술원 처분규제실)
  • Received : 2020.01.06
  • Accepted : 2020.01.10
  • Published : 2020.02.29
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Abstract

In this study, a procedure was introduced to estimate strength and deformation modulus of the 3-D discrete fracture network(DFN) systems using the distinct element method(DEM). Fracture entities were treated as non-persistent square planes in the DFN systems. Systematically generated fictitious fractures having similar mechanical characteristics of intact rock were combined with non-persistent real fractures to create polyhedral blocks in the analysis domain. Strength and deformation modulus for 10 m cube domain of various deterministic and stochastic 3-D DFN systems were estimated using the DEM to explore the applicability of suggested method and to examine the effect of fracture geometry on strength and deformability of DFN systems. The suggested procedures were found to effective in estimating anisotropic strength and deformability of the 3-D DFN systems.

본 연구는 개별요소법을 이용하여 삼차원 불연속절리망 시스템의 강도 및 변형계수를 추정하기 위해 제안된 기법을 소개하였다. DFN(discrete fracture network) 시스템에서 개별 절리는 유한 길이의 정사각 평면으로 취급하였다. 해석영역은 무결암과 유사한 거동을 하도록 설정된 가상절리와 실제 개별 절리의 조합으로 형성된 다면체로 이산화하였다. 제안된 기법의 적용성을 검토하기 위하여 확정적 및 추계론적 삼차원 DFN 시스템으로 이루어진 한 변이 10m인 정육면체 해석영역에 대하여 개별요소법에 의한 강도 및 변형계수를 추정하는 수치실험이 수행되었다. 또한, 본 연구는 절리의 기하학적 속성이 DFN 시스템의 강도 및 변형 특성에 미치는 영향을 살펴보았다. 제안된 기법은 삼차원 DFN 시스템의 이방적 강도 및 변형 특성을 효과적으로 추정하는 것으로 평가되었다.

Keywords

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