대한토목학회논문집 (KSCE Journal of Civil and Environmental Engineering Research)

  • 제33권3호
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  • Pages.1017-1025
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  • 2013
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  • 1015-6348(pISSN)
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  • 2799-9629(eISSN)
대한토목학회 (Korean Society of Civil Engeneers)
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불포화 풍화토 사면의 모관흡수력 분포에 대한 지반조건과 강우강도의 영향

Influence of Soil Characteristic and Rainfall Intensity on Matric Suction of Unsaturated Weathered Soil Slope

  • 김용민 (연세대학교 토목환경공학과) ;
  • 이광우 (연세대학교 토목환경공학과) ;
  • 김정환 (연세대학교 토목환경공학과)
  • 투고 : 2012.06.06
  • 심사 : 2013.04.01
  • 발행 : 2013.05.30
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초록

본 연구에서는 강우 침투에 의한 사면의 모관흡수력 분포특성을 분석하기 위하여 수리학적-역학적 특성을 고려한 동시연계해석을 수행하였다. 이를 위해, 국내 3가지 지역에서 채취한 풍화토를 대상으로 함수특성곡선(SWCC)을 산정하였으며, 이를 토대로 지반조건, 강우특성, 사면경사에 따른 모관흡수력의 변화를 관측하였다. 그 결과, 강우강도가 증가함에 따라 사면내의 모관흡수력은 급격히 감소하는 경향이 나타났으며, 사면 경사에는 큰 영향을 받지 않는 것으로 나타났다. 또한 강우강도보다 포화투수계수가 작은 지반은 표층에서 포화가 쉽게 일어나는 것을 확인하였으며, 다층으로 존재하는 경우에도 사면표층 지반의 수리학적 특성이 모관흡수력 분포에 큰 영향을 주는 것으로 나타났다.

The monolithically coupled finite element analysis for a deformable unsaturated soil slope is performed to investigate matric suction distribution on a soil slope subjected to rainfall infiltration, which can consider the hydraulic-mechanical characteristics for the analysis. The soil-water characteristic curves (SWCC) are experimentally determined to estimate three types of hydraulic properties of domestic areas. Based on the physical properties, the distribution of matric suction is investigated by considering the major factors, such as soil conditions, rainfall intensities, and slope angles. It is found from the results of this study that the matric suction rapidly decreases with an increase in rainfall intensity, regardless a slope angle. The slope surface is more easily saturated when its saturated hydraulic conductivity is smaller than rainfall intensity, and for the case of multi-layered soil slope, hydraulic characteristics of slope surface has a significant influence on matric suction distribution.

키워드

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피인용 문헌

  1. Influence of Antecedent Rainfall in Stability Analysis of Unsaturated Soil Slope vol.35, pp.5, 2015, https://doi.org/10.12652/Ksce.2015.35.5.1073
  2. Slope Stability Assessment on a Landslide Risk Area in Ulsan During Rainfall vol.32, pp.6, 2016, https://doi.org/10.7843/kgs.2016.32.6.27