점토함량에 따른 미고결 이암의 시간 의존적 변형 비교

Comparison of Time-Dependent Deformation in Unconsolidated Mudstones with Different Clay Content

  • 장찬동 (충남대학교 지질환경과학과) ;
  • 명우호 (충남대학교 지질환경과학과) ;
  • 이태종 (한국지질자원연구원 지하수지열연구부)
  • Chang, Chan-Dong (Department of Geology, Chungnam National University) ;
  • Myoung, Woo-Ho (Department of Geology, Chungnam National University) ;
  • Lee, Tae-Jong (Groundwater & Geothermal Resources Division, Korea Institute of Geoscience & Mineral Resources)
  • 발행 : 2008.06.30

초록

점토함량에 따른 미고결 이암의 시간 의존적 변형을 비교하기 위해 측방변형이 구속된 상태에서의 일축압밀시험을 수행하였다. 미고결 이암의 변형은 응력의 증가에 따른 즉각적인 변형과 일정한 응력 하의 크리프 변형으로 구분되었다. 응력 증가분이 동일한 경우에 시간 의존적 변형은 거의 일정한 크기로 발생하였으며 응력 증가분이 증가할수록 크리프변형의 크기도 증가하여 선형점성변형의 특성을 보였다. 점토함량이 증가함에 따라 시간 의존적 변형은 증가하는 경향을 보여 점토가 이암의 시간 의존적 변형 발생에 중요한 역할을 하는 것으로 사료된다. 크리프 변형은 시간에 따라 지수함수 형태를 보여 크립 모델 중 하나인 power-law 모델로 잘 예측될 수 있었다.

We conducted uniaxial consolidation tests in mudstone samples with different clay content, in order to investigate time-dependent deformation and its characteristics. A significant amount of time-dependent strain was observed at a constant stress level immediately after a jump of stress was applied. For a given mudstone, the amount of time-dependent deformation was nearly proportional to the increment of stress, suggesting a linear viscous rheology. The amount of time-dependent strain increases with clay content, implying that clay plays an important role in creep of the unconsolidated mudstone. A power-law model was suitably applied to our results, suggesting that a short-term prediction of time-dependent deformation of the mudstone is tentatively feasible.

키워드

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