Journal of the Korean Geotechnical Society (한국지반공학회논문집)

Korean Geotechnical Society (한국지반공학회)
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Effect of the Overlapping Smear Zone on the Consolidation of Clayey Soil

스미어 영역 겹침이 점성토 지반의 압밀에 미치는 영향

  • Yune, Chan-Young (Dept. of Civil Engrg., Gangneung-Wonju National Univ.) ;
  • Kim, Beom-Jun (Dept. of Civil Engrg., Gangneung-Wonju National Univ.) ;
  • Kang, Hee-Woong (Dept. II Geotechnical Division., DASAN Engineering Co, Ltd)
  • 윤찬영 (강릉원주대학교 토목공학과) ;
  • 김범준 (강릉원주대학교 토목공학과) ;
  • 강희웅 (다산이엔지 지반사업팀)
  • Received : 2012.05.17
  • Accepted : 2013.04.01
  • Published : 2013.04.28
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Abstract

To simulate the soft ground improved by vertical drain method and to investigate the effect of overlapping smear on subsequent consolidation behavior, a series of consolidation tests with a large consolidation chamber and mandrel insertion device were conducted. Based on the test result, numerical analysis was also performed to analyze the efficiency of the vertical drain method. Laboratory test and numerical analysis results showed that the effect of smear zone increased consolidation settlement but the overlapping smear zone decreased the consolidation settlement. In addition, vertical drain accelerated consolidation rate but narrowing the drain spacing did not affect the consolidation rate because of the effect of smear. The efficiency of consolidation rather decreased substantially when the smear zone was overlapped.

본 연구에서는 스미어가 발생한 지반을 모사하고 배수재 간격비에 따른 스미어 영역 겹침 유 무가 차후의 압밀거동에 미치는 영향을 분석하기 위해 대형압밀챔버와 맨드렐 관입시험기를 이용하여 다양한 실내모형실험을 수행하였다. 또한, 이를 바탕으로 유한요소해석을 실시하였고 연직배수공법의 효율성을 분석하였다. 실험 및 해석결과 스미어 발생은 침하량을 증가시키지만 스미어 겹침은 반대로 침하량을 감소시키는 경향을 보였다. 또한 연직배수재를 설치하면 압밀이 촉진되지만 배수재 간격을 줄여도 스미어의 영향으로 압밀속도는 크게 빨라지지 않았으며, 오히려 스미어 영역이 겹칠 정도로 배수재 간격을 줄이면 압밀효율이 급격히 떨어지는 것으로 나타났다.

Keywords

References

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