A Study on Permeability Characteristics of Damaged Granite

화강암 공시체의 응력레벨에 따른 투수특성에 대한 연구

  • Kim, Jong-Tae (Department of Earth and Environmental Sciences, Andong National University) ;
  • Seiki, T. (Department of Civil Engineering, Utsunomiya University) ;
  • Kang, Mee-A (Department of Environmental Engineering, Andong National University) ;
  • Jeong, Gyo-Cheol (Department of Earth and Environmental Sciences, Andong National University)
  • 김종태 (안동대학교 지구환경과학과) ;
  • ;
  • 강미아 (안동대학교 환경공학과) ;
  • 정교철 (안동대학교 지구환경과학과)
  • Published : 2007.03.30

Abstract

Although rock itself has high strength or low permeability, engineering properties of rock masses are significantly influenced by discontinuities such as cracks and joints. Considered with possibility of groundwater flow in massive rock mass of deep subsurface, the connectivity of micro cracks should be analyzed as a conduit of ground-water flow. The objective of this study is to estimate permeability characteristics of granite dependent on damage process with application of joint distribution analysis and modeling of permeability analysis in rock masses. In case of average permeability coefficients, the modeling results based on micro cracks data are well matched with the results from permeability tests. Based on the visualization result of three dimensional model, the average permeability coefficients through the discharge plane have a positive relationship with the number of microcrack induced by rock damage.

토목구조물의 기초가 되는 암반은 암석자체로서는 강도가 높고 투수성이 작지만 공학적 성질은 암반내의 존재하는 크랙, 절리 등 불연속면의 영향을 크게 받는다. 천부 암반내에 지배적으로 분포하는 것은 절리이지만 그 수가 적은 지하심부에 있어서 지하수 투수성의 가능성을 고려하면 암석자체의 미소크랙의 연결성이 투수성 크랙으로서 충분히 고려되어져야 한다. 이 연구에서는 절리성 암반의 절리분포 및 투수성 해석 모델화 방법을 화강암 공시체의 미소크랙에 응용하여 손상진행에 따른 화강암의 투수 특성을 추정하는 것을 목적으로 하였다. 미소크랙 데이터로부터 투수모델을 작성하여 해석한 결과 평균투수계수에 있어서 실제의 투수시험 값과 잘 일치하는 것으로 나타났다. 또한 3차원 모델의 가시화를 가지고 모델표면에서의 미소크랙과의 비교로부터 손상발달에 의한 미소크랙 발생수와 유출면으로부터 계산한 평균투수계수는 비례관계로 실험결과와 잘 일치하는 것으로 해석되었다.

Keywords

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