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Research Article

The Study on The Numerical Analysis Method for Ground Improved by Cement Mixing Method

시멘트혼합처리공법이 적용된 지반의 수치해석 방법에 관한 연구

Byung-Il Kim1*
,
Kang-Han Hong2
,
Young-Seon Kim3
,
Sang-Jae Han4
김 병일1*
,
홍 강한2
,
김 영선3
,
한 상재4
1Member, Research Director, Expert Group For Earth & Environment, #1020, 53 Seonggogae-ro, Uiwang-si, Gyeonggi-do 16006, Republic of Korea
2Member, General Manager, Expert Group For Earth & Environment, #1020, 53 Seonggogae-ro, Uiwang-si, Gyeonggi-do 16006, Republic of Korea
3Member, Manager, Expert Group For Earth & Environment, #1020, 53 Seonggogae-ro, Uiwang-si, Gyeonggi-do 16006, Republic of Korea
4Member, President, Expert Group For Earth & Environment, #1020, 53 Seonggogae-ro, Uiwang-si, Gyeonggi-do 16006, Republic of Korea
* Corresponding Author
30 December 2018. pp. 41-52
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Abstract

Since the composite ground design method is easy to apply for calculation or numerical analysis, it is applied to the design of cement mixing methods. However, the comparison studies between analysis and actual results such as a trial test and construction for the cement mixing method are few because the composite ground design method was developed for the compaction pile (SCP, GCP) methods. In this study, the results of various analysis methods, such as the composite ground analysis method (1 case) and the individual pile method (3 cases), were compared with actual measurements through a two-dimensional finite element numerical analysis. In case of the surface settlements, the results of study show that the individual plate method was larger than the actual measurements, while other methods are similar. The settlements at the under ground of the improved area is overestimated in all analysis methods. When comparing numerical analysis results for the horizontal displacement, and ground reaction forces, the individual pile method in equivalent wall concept was found to be the most similar to the measurements. The composite ground method was not able to predict the behavior of stress transfer (Arching effect) and it turned out that the prediction of horizontal displacement was too large.

Keywords
Composite ground
Cement mixing
Numerical analysis

복합지반 설계법은 계산이나 수치해석시 적용하기 편리하여 시멘트혼합처리공법의 설계시 많은 설계자들에 의해 적용되고 있다. 그러나, 복합지반 설계법은 다짐말뚝공법(SCP, GCP)에 관하여 개발된 것으로 시멘트혼합처리공법에 대한 시험시공 등의 실제 결과와의 비교 분석은 미미하다. 본 연구에서는 2차원 유한요소 수치해석을 통해 복합지반 해석법, 개별말뚝해석법 등 다양한 해석법의 결과를 실측과 비교 분석하였다. 본 연구 결과, 지표면에서의 침하는 Plate 요소만을 적용하는 방법의 침하량이 실측에 비해 크게 예측되었고, 기타 방법은 유사한 것으로 나타났다. 개량지반 직하부에서만 발생된 침하량의 크기가 크게 나타났고, 침하량, 수평변위 및 지반반력 등에 대하여 실측과 수치해석 결과를 비교하면 등가벽 개념의 개별말뚝 해석법이 가장 유사한 것으로 나타났다. 복합지반법의 경우 응력전이(지반아칭) 현상을 예측하지 못하였고, 수평변위를 과대 예측하는 것으로 나타났다.

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Information
  • Publisher :Korean Geosythetics Society
  • Publisher(Ko) :한국지반신소재학회
  • Journal Title :Journal of the Korean Geosynthetics Society
  • Journal Title(Ko) :한국지반신소재학회 논문집
  • Volume : 17
  • No :4
  • Pages :41-52
  • Received Date : 2018-10-15
  • Revised Date : 2018-11-01
  • Accepted Date : 2018-11-09
  • DOI :https://doi.org/10.12814/jkgss.2018.17.4.041
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