Economic and Environmental Geology (자원환경지질)

The Korean Society of Economic and Environmental Geology (대한자원환경지질학회)
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Modeling Study for Effects of Hydrothermal Clay Vein on Slope Stability

열수변질 점토맥이 사면 안정성에 미치는 영향에 관한 모델링 연구

  • Jo, Hwan-Ju (Department of Earth and Environmental Sciences, Korea University) ;
  • Jo, Ho-Young (Department of Earth and Environmental Sciences, Korea University) ;
  • Jeong, Kyung-Mun (Dohwa Consulting Engineers Co. Ltd.)
  • 조환주 (고려대학교 지구환경과학과) ;
  • 조호영 (고려대학교 지구환경과학과) ;
  • 정경문 ((주)도화종합기술공사)
  • Received : 2010.03.30
  • Accepted : 2010.04.20
  • Published : 2010.04.28
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Abstract

Clay veins that occurred in a slope by hydrothermal alteration, can significantly affect its slope stability. The effect of clay veins on the slope stability was investigated by numerical modeling study. Various parameters such as cohesion, internal friction angle, orientation, groundwater level, rainfall intensity and duration, have been modelled. As shear strength increased, factor of safety increased. As groundwater level developed, factor of safety decreased. For the case of slip surface developed on interface, factor of safety was lower than that for case of slip surface developed on either weathered soil or clay vein. The effect of various soil types of the slope stability was also investigated by simulating seepage through the slopes with various soils. The groundwater level significantly increased on the slopes with silty and generic soils. For the slope with sandy soil, almost no change in groundwater level was observed due to rapid drainage.

열수변질에 의한 점토맥이 존재하는 사면 발생시 사면의 안전성에 영향을 미치는 것으로 알려져 있다. 파괴면의 형성 위치에 따라 접촉면 조건과 비접촉면 조건으로 분류하여 점토맥의 점착력, 내부마찰각, 방향성, 지하수위, 강우강도, 강우 지속시간 등의 인자에 따라 점토맥이 사면 안전율에 미치는 영향을 수치 모델링 연구를 통해 조사하였다. 지반 정수가 클수록 사면 안전율이 증가하였다. 사면 내 지히수위가 상승하면 사면 안전율이 감소하는 것을 확인하였다. 다양한 토양에 대한 강우 침투 모델링 결과 이질토는 강우강도에 따라 다양한 지하수위 발달 경향을 보인다. 반면에 사질토는 빠른 배수로 인해 지하수위의 상승이 거의 나타나지 않았다. 따라서 점토맥이 존재하는 사면에서 사질토는 이질토에 비해 사면 안전율에 미치는 영향이 적었다.

Keywords

References

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