Landslide Analysis Using the Wetting-Drying Process-Based Soil-Water Characteristic Curve and Field Monitoring Data

Seong-Cheol Lee; Moon-Hyun Hong; Sang-Seom Jeong

doi:10.7843/kgs.2023.39.5.13

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2023 Vol.39, Issue 5 Preview Page Next Page

Landslide Analysis Using the Wetting-Drying Process-Based Soil-Water Characteristic Curve and Field Monitoring Data 현장 함수비 모니터링과 습윤-건조 함수특성곡선을 이용한 산사태 취약성 분석

31 May 2023. pp. 13-26

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Abstract

This study examined the soil-water characteristic curve (SWCC), considering the volume change, using wetting curves on the field monitoring data of a wireless sensor network. Special attention was given to evaluating the landslide vulnerability by deriving a matric suction suitable for the actual site during the wetting process. Laboratory drying SWCC and shrinkage laboratory tests were used to perform the combined analysis of landslide and debris flow. The results showed that the safety factor of the wetting curve, considering the volume change of soil, was lower than that of the drying curve. As a result of numerical analyses of the debris flow simulation, more debris flow occurred in the wetting curve than in the drying curve. It was also found that the landslide analysis with the drying curve tends to overestimate the actual safety factor with the in situ wetting curve. Finally, it is confirmed that calculating the matric suction through SWCC considering the volume change is more appropriate and reasonable for the field landslide analysis.

Keywords

Debris flow

Hysteresis

Landslide

Soil-water characteristic curve

Unsaturated shear strength

Volume change

Volumetric water content

Wireless sensor network monitoring

불포화토의 함수특성곡선은 산사태 평가와 토석류 분석에 매우 중요한 요소이다. 본 연구에서는 현장에 적합한 모관흡수력을 통해 산사태 취약성을 분석하기 위하여 함수특성곡선과 체적변형을 고려한 수축시험을 수행하였다. 실험에 사용된 시료는 국내에 분포하는 세립분이 다량함유된 SM계열 화강 풍화토이며, 산사태 해석 시 사용된 강수량의 경우 실측된 데이터를 사용하였다. 실내실험 시 측정된 함수특성곡선은 건조과정에서 발생 된 곡선이며, 체적변형 확인할 수 있는 수축시험을 통하여 습윤과정에서 발생되는 곡선을 재 산정하여 산사태 취약성 분석을 하였다. 본 연구결과 습윤곡선의 안전율이 건조곡선의 안전율보다 낮게 나타남을 알 수 있었으며 그 결과 현장 사면지반의 체적변형을 고려한 모관흡수력 산정이 필요함을 확인 하였다.

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Information

Publisher :The Korean Geotechnical Society
Publisher(Ko) :한국지반공학회
Journal Title :Journal of the Korean Geotechnical Society
Journal Title(Ko) :한국지반공학회 논문집
Volume : 39
No :5
Pages :13-26
Received Date : 2023-03-03
Revised Date : 2023-05-03
Accepted Date : 2023-05-03
DOI :https://doi.org/10.7843/kgs.2023.39.5.13

Journal of the Korean Geotechnical Society ISSN:1229-2427(Print) 2288-646X(Online) 한국지반공학회 논문집

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