Experimental Study on the Triaxial Compressive Behaviour of Unsaturated Soil

불포화토의 삼축압축거동에 관한 실험적 연구

  • Kim, Young-Seok (Dept. of Geotechnical Engineering, Korea Institute of Construction Technology) ;
  • Oka, Fusao (Dept. of Civil and Earth Resources Engineering, Kyoto University) ;
  • Cho, Sam-Deok (Dept. of Geotechnical Engineering, Korea Institute of Construction Technology)
  • 김영석 (한국건설기술연구원 지반연구부) ;
  • 오카 후사오 (교토대학 공학연구과 사회기반공학) ;
  • 조삼덕 (한국건설기술연구원 지반연구부)
  • Published : 2006.03.24

Abstract

It has been recognized unsaturated soil behaviour playing an important role in geomechanics. Up to now, only a few experimental data are available for the technical difficulties related to both volume changes and suction measurements. In this study, the volume changes of unsaturated compacted silty soil were monitored with proximeter (i.e. non-contactable transducer) during various triaxial compression tests, which gave a realistic estimation in the volume changes of unsaturated soil sample. The measurement of volume changes were performed with 0.5% of the maximum error under the axial strain ratio of less than 10%. The experimental results have revealed that the mechanical behaviour of unsaturated soil can be significantly affected by the matric suction. During the shearing processes, the level of maximum deviator stress under the initial suction pressure of 50kPa was higher than that under the initial suction pressure of 10kPa. On the other hand, the volume changes became smaller under the increase in the initial suction pressure.

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