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2018 Vol.34, Issue 3
Back Analysis of Unsaturated Hydraulic Conductivities for Transient Water Release and Imbibitions Measurement

부정류 유출 및 흡입시험에 대한 불포화 투수계수의 역해석

Seboong Oh1*
,
Do-Hyung Kim2
,
Young-Sug Song3
오 세붕1*
,
김 도형2
,
송 영석3
1Prof., Dept. of Civil Eng., Yeungnam Univ.
2M.Sc., Dept. of Civil Eng., Yeungnam Univ.
3Principal Researcher, Geologic Environment Division, Korea Institute of Geoscience and Mineral Resources
1영남대학교 건설시스템공학과 교수
2영남대학교 건설시스템공학과 석사
3한국지질자원연구원 지질환경연구본부 책임연구원
*교신저자. *Corresponding Author. 
31 March 2018. pp. 5-12
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Abstract

Tests for transient water release and imbibitions measurement were conducted to estimate the unsaturated hydraulic conductivities by using back analysis. By using transient hydraulic characteristics, both the soil water retention curve and hydraulic conductivity fuction can be evaluated effectively and accurately. In this study the experiment for three samples were conducted accurately to measure the change of water content with time for various steps of matric suction. The back analysis calculated the amount of transient flow reliably in comparison with the experimental results. In the soil water retention curve there was no significant difference between the result of back analysis and that of experiment. The hydraulic conductivity function from back analysis was compared with the theoretical relation based on retention curve but they showed much difference. However, the unsaturated hydraulic behavior obtained by the combination of experimental and analytical techniques are considered to agree with the actual behavior.

Keywords
Unsaturated soil
Hydraulic conductivity
Soil water retention

불포화 투수계수 추정을 위하여 부정류 유출 및 흡입시험을 수행하였고 그 결과를 이용하여 역해석을 수행하였다. 부정류 수리특성을 이용하면 함수특성곡선 및 불포화투수계수를 정확하고 효율적으로 구할 수 있다. 본 연구에서 세가지 시료에 대한 실험을 세분화된 모관흡수력에 대하여 실행하고 시간에 따른 함수비의 변화를 정밀하게 측정하였다. 역해석과 실험결과를 비교한 결과, 시간에 따른 유량의 변화를 신뢰성 있게 계산할 수 있었다. 역해석의 해로 구한 함수특성곡선에서는 실험결과와 근사하게 나타났다. 불포화 투수계수곡선에서는 함수특성곡선으로부터 이론적으로 구한 곡선과 비교하였으나 역해석 결과와는 다소 차이를 보였다. 하지만 실험적 및 해석적 기법을 병행하여 획득한 불포화 수리적 거동이 실제거동에 부합된다고 판단된다.

References
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Fredlund, D. G., Xing, A., and Huang, S. (1994), “Predicting the Permeability Function for Unsaturated Soils Using the Soil-water Characteristic Curve”, Canadian Geotechnical Journal, Vol.31, No.3, pp.533-546.
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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 : 34
  • No :3
  • Pages :5-12
  • Received Date : 2017-10-24
  • Revised Date : 2018-03-12
  • Accepted Date : 2018-03-13
  • DOI :https://doi.org/10.7843/kgs.2018.34.3.5
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