Tunnel and Underground Space (터널과지하공간)

Korean Society for Rock Mechanics and Rock Engineering (한국암반공학회)
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Pattern of Shear-induced Fracture Development in en Echelon Array : Discrete-element Approach

전단변형 시 안행상 균열의 끝에서 형성되는 새로운 균열 발달 형태 연구 : 개별요소적 접근

  • 권순달 ((주)희송지오텍 자원환경사업부) ;
  • 유승완 (대우인터내셔널 석유가스탐사실) ;
  • 권상훈 (연세대학교 지구시스템과학과) ;
  • 김기석 ((주)희송지오텍)
  • Received : 2015.06.23
  • Accepted : 2015.07.27
  • Published : 2015.08.31
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Abstract

Rock masses include various rock discontinuities such as faults, joints, and bedding planes. These discontinuities appear as complex structures in geometry. In this study, growth patterns of fractures between two stepping shear fracture tips are numerically modeled using PFC2D (Particle Flow Code). The numerical model showed not only incipient growth of fractures at the tips of preexisting fractures but also subsequent growth of the new fractures. It is observed from all of the experiments that the incipient fractures are tensile cracks developed at $30{\sim}57^{\circ}$ to the preexisting fractures and the subsequent growth of these fractures were at low angles to the preexisting fractures this study.

암반에는 단층, 절리, 층리 등의 불연속면이 많이 포함되어 있다. 이러한 불연속면은 기하학적 복합성에 의해 복잡한 구조로 나타난다. 이 연구는 스텝으로 배열된 두 전단균열의 끝에서 나타나는 구조 발달을 수치해석적으로 연구하였다. 이 연구에서는 PFC2D(Particle Flow Code) 프로그램을 이용하여 두 전단균열의 끝에서 형성되는 초기균열(incipient fracture)뿐만 아니라 초기균열에서 덧자라는 균열의 성장과정을 살펴보았으며, 균열 발생 시 나타나는 주변응력상태를 관찰하였다. 모든 실험 결과에서는 균열 끝에서 발생한 초기 균열 대부분이 인장균열에 의한 것으로 나타났으며, 균열의 전파각은 초기에 $30{\sim}57^{\circ}$에서 실험이 더 진행되면 저각으로 발달하는 것으로 나타났다.

Keywords

References

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