Journal of the Korean Society of Hazard Mitigation (한국방재학회 논문집)

Korean Society of Hazard Mitigation (한국방재학회)
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Slope Stability Analysis based on Probabilistic Characteristics of Unsaturated Soil Properties of Weathered Granite Soil

화강풍화토의 확률론적 불포화 지반정수 특성에 따른 사면안정해석

  • 전경한 (한국과학기술원 건설 및 환경공학과) ;
  • 이승래 (한국과학기술원 건설 및 환경공학과) ;
  • 윤석 (한국과학기술원 건설 및 환경공학과) ;
  • 김윤태 (국립부경대학교 해양공학과)
  • Received : 2012.10.09
  • Accepted : 2012.10.23
  • Published : 2013.02.28
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Abstract

The unsaturated soil properties such as soil-water characteristic curve, unsaturated permeability and unsaturated shear strength, always involve uncertainties associated, making it hard to obtain a representative value in analyzing the stability of slopes. Because a deterministic approach use a representative value, soil properties with severe variance sometimes lead to misestimate and hence the consequence also varies from person to person. To address this problem, a probabilistic approach to the analysis of slope stability has been adopted. Even though the probabilistic characteristics of soil are essential for probabilistic approach, it has not been established. Therefore, in this paper, the probabilistic characteristics of the unsaturated soil properties were defined. A simple procedure for the probabilistic approach was proposed to obtain the unsaturated soil properties for the slope stability analysis. Finally, the probabilistic analysis of unsaturated slope stability using monte-carlo simulation method was conducted for the Korean weathered granite soil.

함수특성곡선, 불포화투수곡선, 불포화전단강도와 같은 불포화 지반정수는 필연적으로 불확실성을 내포하기 때문에 사면안정해석에 사용될 대표적인 값을 획득하기 힘들다. 결정론적인 방법은 하나의 대표적인 값을 사용하기 때문에 분산이 심한 지반정수일 경우 잘못된 평가를 초래할 수 있다. 이를 해결하기 위해 확률론적 해석방법이 이용되고 있다. 하지만 지반정수에 대한 확률론적 특성 연구가 확률론적 해석을 위해 선행되어야 함에도 불구하고, 불포화 지반정수에 대한 확률론적 특성 연구는 아직 부족한 실정이다. 따라서 본 연구에서는 국내 화강풍화토의 불포화 지반정수에 대한 확률론적 특성을 파악하고, 이를 바탕으로 사면안정해석을 위한 불포화지반정수를 획득하기 위한 간단한 절차도를 제안하였다. 또한 불포화 화강풍화토 사면에 대하여 몬테카를로 시뮬레이션 방법을 사용한 확률론적 사면안정해석을 수행하였다.

Keywords

Acknowledgement

Supported by : 한국연구재단, 한국건설교통기술평가원

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