Tunnel and Underground Space (터널과지하공간)

Korean Society for Rock Mechanics and Rock Engineering (한국암반공학회)
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Influence of Joint Secondary Roughness on Roughness Parameter in Direct Shear Test

직접전단시험에서 절리면의 2차 거칠기가 거칠기 정량화 파라미터에 미치는 영향

  • Lee, Deok-Hwan (Dept. of Energy & Resources Engineering, Kangwon National University) ;
  • Choi, Sung-Oong (Dept. of Energy & Resources Engineering, Kangwon National University)
  • 이덕환 (강원대학교 에너지.자원공학과) ;
  • 최성웅 (강원대학교 에너지.자원공학과)
  • Received : 2014.01.28
  • Accepted : 2014.02.18
  • Published : 2014.02.28
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Abstract

Rock joint surface roughness, which is known to be one of the most important factors for defining shear strength of rock mass, has been researched in various methods. However, approaches to separate a roughness into two groups (primary and secondary) for evaluating the roughness have been rarely performed. In this study, elements of secondary roughness were eliminated through direct shear testing with tensile joint specimen and they were quantified with joint parameters. It is revealed that roughness parameters decrease with increasing the normal stress and sampling intervals, except for the case in which the normal stress is larger than 1.5 MPa. Also it is analyzed that ratio of area reduction in the opposite direction of shearing decreases with increasing the roughness parameter.

절리면의 전단강도를 결정하는 중요한 인자로 알려진 암반 절리면의 거칠기는 여러 가지 방법에 의해 연구되어 왔다. 하지만, 거칠기를 구성하는 요소인 1차 거칠기와 2차 거칠기를 분리하여 거칠기를 평가하려는 시도는 매우 제한적으로 수행되고 있다. 본 연구에서는 인장절리 시험편을 이용하여 직접전단시험을 통해 2차 거칠기 요소를 파괴하고 이를 거칠기 파라미터를 이용하여 정량화 하였다. 거칠기 파라미터는 수직응력과 측정 간격이 증가할수록 감소하였으나, 1.5 MPa 이상의 수직응력에서는 일정한 경향을 나타내지 않았다. 또한 전단 반대방향의 거칠기 면적 감소율은 거칠기 파라미터가 증가할수록 감소하였다.

Keywords

References

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