Journal of the Korean Geotechnical Society (한국지반공학회논문집)

Korean Geotechnical Society (한국지반공학회)
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Undrained Characteristics of Geogrid-Encased Stone Column under Cyclic Load Using Reduced-Scale Model Tests

축소모형실험에 의한 반복하중 작용시 지오그리드 감쌈 쇄석말뚝의 비배수 거동 특성

  • 최진욱 (성균관대학교 초고층장대교량학과) ;
  • 이대영 (한국건설기술연구원 지반공학연구실) ;
  • 유충식 (성균관대학교 사회환경시스템공학과)
  • Received : 2012.10.26
  • Accepted : 2013.01.10
  • Published : 2013.01.31
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Abstract

This paper presents the results of a laboratory investigation into a study on undrained characteristics of a geogrid-encased stone column (GESC) installed in soft clay under cyclic load. In order to analyze behavior of settlement, pore water pressure, stress concentration ratio and strain of the GESC compared to a stone column, a series of reduced-scale laboratory tests were performed. The model tests show that GESC provides a simple and effective method of deformation resistance and settlement restraint when a short-term cyclic load is applied. The maximum strain of geogrid occurred at 1.2D and 1.5D from the top of the column. This paper highlights the importance of considering overlay effect and replacement ratio on cyclic load supporting GESC.

본 논문에서는 반복하중 작용시 연약지반에 설치된 토목섬유 감쌈 쇄석말뚝의 비배수거동특성을 다루었다. 모형실험을 통해 점성토 지반에 적용된 지오그리드 감쌈 쇄석말뚝의 침하량, 과잉간극수압, 응력분담비 그리고 지오그리드 변형률의 변화특성을 기존의 쇄석말뚝과 비교하여 분석하였다. 실험결과를 통하여 연약지반에 설치된 GESC는 단기하중 재하시 쇄석기둥의 변형을 토목섬유의 인장력으로 구속 시켜 변형저항력의 증가와 침하저감 효과가 있음을 알 수 있으며 지오그리드의 최대 변형률은 1.2D와 1.5D에서 발생하는 것으로 나타났다. 본 논문에서는 반복하중 재하시 지오그리드 감쌈 쇄석말뚝에서의 지오그리드 감쌈 효과와 치환율이 쇄석말뚝에 미치는 영향을 고찰하였다.

Keywords

References

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