Journal of the Korea Academia-Industrial cooperation Society (한국산학기술학회논문지)

The Korea Academia-Industrial cooperation Society (한국산학기술학회)
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Case Study of Stress Concentration Ratio of Composite Ground Improved by Deep Cement Mixing Method

심층혼합처리공법으로 개량된 복합지반의 응력분담비에 대한 사례 연구

  • Yoo, Wan-Kyu (Department of Civil and Environmental Engineering, Myongji University) ;
  • Kim, Byoung-Il (Department of Civil and Environmental Engineering, Myongji University) ;
  • Kim, Young-Uk (Department of Civil and Environmental Engineering, Myongji University)
  • 유완규 (명지대학교 토목환경공학과) ;
  • 김병일 (명지대학교 토목환경공학과) ;
  • 김영욱 (명지대학교 토목환경공학과)
  • Received : 2012.04.05
  • Accepted : 2012.07.12
  • Published : 2012.07.31
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Abstract

Deep cement mixing method (DCM) is one of the most effective improving methods for deep soft ground. The strength of soft soil can be increased in a short period of time with less noise and vibration. However, it is necessary to determine the stress transferring and concentration ratio of the composite soft ground for estimating the settlement behaviors. In this study, a model test was undertaken to investigate the stress distribution of the improved soil. Results of the model test shows that stresses were concentrated mainly on the improved areas by DCM and the concentration ratios (35.4, 28.6, 27.02) were obtained using several different techniques. These were well in accordance with other previous research results (26.52, 32.5).

심층혼합처리(deep cement mixing, DCM)공법은 두꺼운 연약지반을 개량하는 공법 중 하나이다. 이 공법은 저소음, 저진동으로 공해가 적고 단시간에 큰 강도를 얻을 수 있는 장점이 있다. DCM공법과 같이 연약지반 개량 후 복합지반이 형성되는 지반의 침하량 산정을 위해서는 응력분담비의 결정이 필요하다. 이 연구에서는 DCM공법으로 개량된 복합지반 거동특성을 이해하기 위하여 모형재하시험을 실시하였다. 모형시험에서 측정한 토압과 침하량, 그리고 기존 제안도표를 이용하여 응력분담비를 산정하였는데 응력분담비는 각각 35.4, 28.6, 27.02로 DCM 개량체에 큰 응력집중이 발생하는 것으로 나타났다. 이러한 결과는 기존 연구결과에 의한 응력분담비(26.52, 32.5)와 비교할 때 유사한 값을 갖는 것으로 나타났다.

Keywords

References

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