KSCE Journal of Civil and Environmental Engineering Research (대한토목학회논문집)

Korean Society of Civil Engeneers (대한토목학회)
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Spatial Variation of Void Ratio and Permeability by Smear and Its Changing Behavior during Consolidation :Part I. Physical Model Test and Analysis

스미어로 의한 점성토 지반의 간극비 및 투수계수의 위치별 차이와 압밀 중 변화 거동에 대한 연구 : Part I. 실험 및 거동 분석

  • 윤찬영 (강릉원주대학교 토목공학과) ;
  • 손대진 (현대건설(주) 토목환경사업부 설계팀) ;
  • 천성호 (대림산업(주) 기술연구소 토목연구지원팀) ;
  • 정충기 (서울대학교 건설환경공학부)
  • Received : 2008.09.01
  • Accepted : 2009.05.19
  • Published : 2009.07.31
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Abstract

In this research, the ground with smeared zone was reconstructed using the large consolidation test apparatus. And the reconstituted kaolinite samples at different locations were retrieved for the oedometer test. From the oedometer test results the permeability- void ratio-effective stress behavior was investigated. Based on the experimental analysis, spatial differences of permeability according to the drainage distance by both smear and radial drainage consolidation reduced as the consolidation proceeds and eventually disappeared in normally consolidated region. And the spatial variation of permeability by radial drainage consolidation showed larger differences in smaller extent than the spatial variation of permeability by smear.

본 연구에서는 대형압밀시험 장비를 이용하여 연직배수재 타설로 스미어가 발생된 지반을 모사하고 실험을 수행하였다. 스미어가 발생한 카올리나이트 모형지반에서 배수재로부터의 거리에 따라 시료를 채취하고 이를 이용하여 표준압밀시험을 실시하였으며, 이로부터 투수계수-간극비-유효응력의 3차원 거동을 분석하였다. 실험결과 스미어 발생으로 나타나는 위치별 투수계수 차이와 스미어와 무관하게 방사배수 압밀 중 나타나는 위치별 투수계수 차이는 모두 압밀진행에 따라 감소하며 정규 압밀영역에서 거의 사라진다. 또한 스미어로 인한 것보다 방사배수 압밀로 인한 위치별 투수계수 차이가 상대적으로 더 작은 영역에서 더 크게 나타났다.

Keywords

References

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