Effect of apparent cohesion in unsaturated soils on the ground behavior during underground excavation

불포화토 겉보기 점착력이 지하굴착시 거동에 미치는 영향

  • 이인모 (고려대학교 건축.사회환경공학부) ;
  • 정지희 ((주)삼보기술단 지반사업부) ;
  • 김경렬 (한국전력공사 전력연구원) ;
  • 김도훈 (고려대학교 건축.사회환경공학부) ;
  • 현기창 (고려대학교 건축.사회환경공학부)
  • Received : 2009.12.16
  • Accepted : 2010.01.06
  • Published : 2010.03.31

Abstract

Gound excavation is frequently executed in unsaturated soil conditions. In this paper, the effect of apparent cohesion in unsaturated soils on the ground behavior during underground excavation is studied. The VPPE (Volumetric Pressure Plate Extractor) test, the unsaturated triaxial test and the trap-door test were carried out to figure out how the behavior of soils varies depending on the variation of apparent cohesion. The test results show that the ground behavior is almost identical if the soil is either fully dry or fully saturated. However, if the soil is partially-saturated with the increase of water content, the ground behaves quite differently. In summary, the apparent cohesion in unsaturated soils plays key roles when excavating underground structures.

Acknowledgement

Supported by : 한국전력공사 전력연구원

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