Comparative Study on Unsaturated Characteristic Curves of Boeun Granite Weathered Soil during Drying and Wetting Paths

건조 및 습윤과정에서 보은 화강암 풍화토의 불포화특성곡선 비교

Song, Young-Suk

  • Received : 2016.04.18
  • Accepted : 2016.06.28
  • Published : 2016.07.31


To investigate the unsaturated characteristics of the Boeun granite weathered soil, matric suction and volumetric water content were measured in both drying and wetting paths using Automated Soil-Water Characteristics Curve Apparatus. Based on the measured results, Soil-Water Characteristics Curve was estimated by van Genuchten (1980) model. The relationship between effective degree of saturation and matric suction showed the non-linear curve with S-shape and the hysteresis phenomenon occurred during drying and wetting paths. Suction Stress Characteristics Curve was estimated by the Lu and Likos (2006) model. The suction stress in drying path was constantly maintained and that in wetting path tended to increase when the effective degree of saturation was low. But the suction stress in drying path was larger than that in wetting path at the same degree of saturation when the effective degree of saturation became larger. Meanwhile, Hydraulic Conductivity Function was evaluated by the van Genuchten (1980) model which is one of the parameter estimation methods. The unsaturated hydraulic conductivity decreased with increasing the matric suction, and the decreasing velocity regarding to the matric suction in drying path was larger than that in wetting path.


Granite weathered soil;Drying and wetting paths;Soil-Water Characteristics Curve;Suction Stress Characteristics Curve;Hydraulic Conductivity Function


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Grant : 실시간 모니터링 기반의 산사태 신속탐지기술 개발

Supported by : 한국지질자원연구원