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2023 Vol.24, Issue 10 Preview Page
Stability Evaluation of Weathered Gneiss Soil Slopes according to Clay Content

점토함유량에 따른 편마풍화토 비탈면의 안정성 평가

Hyunsu Park1
,
Byeongsu Kim2*
박 현수1
,
김 병수2*
1Docteral Student, Doctoral Student, Dept. of Civil & Environ. Eng., Dankook University
2Associate Professor, Dept. of Civil & Environ. Eng., Dankook University
*Corresponding Author
1 October 2023. pp. 15-23
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Abstract

In this study, the infiltration behavior of slopes composed of mixed soils with clay contents of 0%, 5%, and 10% in weathered Gneiss soil, which is a representative weathered soil in Korea, was investigated, and the stability of unsaturated slopes due to rainfall infiltration was examined. For this, in this study, the soil water characteristic curve was obtained through the water retention test, and the strength constant was obtained through the triaxial compression test. Based on the obtained results, the influence of clay content and antecedent rainfall effect (i.e., initial suction) on the formation of saturated zone (i.e., wetting band) and slope stability due to rainfall infiltration was examined through infiltration and stability analyses. As a result, it was found that the higher the initial suction, the slower the formation of the saturated zone on the slope. In addition, it was found that as the clay content increases, the shear strength of the ground increases and the resistance to rainfall infiltration increases, and eventually the slope stability is greatly improved.

Keywords
Clay content
Slope stability
Initial suction
Antecedent rainfall effect
Weathered Gneiss

본 연구에서는 국내의 대표적 풍화토인 편마풍화토에 점토함유량 0%, 5%, 10%의 혼합토로 조성된 비탈면에 대해 강우 시 침투거동을 조사하고, 강우침투로 인한 불포화 비탈면의 안정성을 검토했다. 이를 위해 본 연구에서는 불포화 함수특성시험을 통해 함수특성곡선을 획득했고, 포화 삼축압축시험을 통해 강도정수를 얻었다. 얻어진 결과를 토대로, 침투해석과 안정해석을 통해 비탈면의 강우침투로 인한 포화대 형성과 안전성에 점토함유량과 선행강우 효과를 나타내는 초기흡수력이 미치는 영향에 대해 조사하였다. 그 결과, 지반의 초기흡수력이 높을수록 비탈면의 포화대 형성이 늦춰졌다는 것을 알았다. 또한 점토함유량이 증가할 수록 지반의 전단강도 증대와 더불어 강우침투에 대한 저항성을 높이는 효과를 가지며, 비탈면의 안전성을 크게 향상시킨다는 것을 알 수 있었다.

키워드
점토함유량
비탈면안정성
초기흡수력
선행강우효과
편마풍화토
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Information
  • Publisher :Korean Geo-Environmental Society
  • Publisher(Ko) :한국지반환경공학회
  • Journal Title :Journal of the Korean Geo-Environmental Society
  • Journal Title(Ko) :한국지반환경공학회 논문집
  • Volume : 24
  • No :10
  • Pages :15-23
  • Received Date : 2023-08-03
  • Revised Date : 2023-08-08
  • Accepted Date : 2023-09-25
  • DOI :https://doi.org/10.14481/jkges.2023.24.10.15
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