Journal of the Korean Geotechnical Society (한국지반공학회논문집)

Korean Geotechnical Society (한국지반공학회)
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Load Carrying Capacity of Geosynthetic-Reinforced Stone Column in Cohesionless Ground

사질토 지반에 시공되는 지오그리드 보강 쇄석말뚝의 지지력 거동특성

  • Yoo, Chung-Sik (Dept. of Civil & Environ. Engrg., Sungkyunkwan Univ.) ;
  • Song, Ah-Ran (Dept. of Civil & Environ. Engrg., Sungkyunkwan Univ.) ;
  • Kim, Sun-Bin (Dept. of Civil & Environ. Engrg., Sungkyunkwan Univ.) ;
  • Lee, Dae-Young (Department of Geotechnical Engrg., Korea Institute of Construction Technology)
  • 유충식 (성균관대학교 토목환경공학과) ;
  • 송아란 (성균관대학교 토목환경공학과) ;
  • 김선빈 (성균관대학교 토목환경공학과) ;
  • 이대영 (한국건설기술연구원 국토지반연구부)
  • Published : 2007.05.31
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Abstract

This paper deals with the bearing capacity behaviour of geosynthetic-reinforced stone column(GRSC) constructed in soft ground, as part of an investigation regarding the applicability of GRSC in Korea. In this study, two-dimensional finite element analyses were performed to investigate the effect of relevant design factors on the bearing capacity behaviour. The parametric study is performed for various influencing factors. The results indicated that the geogrid encasement tends to significantly improve the load carrying capacity of a stone column. Also found were that the geogrid encasement length and its stiffness significantly affect the load carrying capacity behaviour of GRSC, and that the encasement length of three times the stone column diameter is sufficient in mobilizing the full reinforcement effect. Practical implications of the findings are discussed.

본 논문에서는 사질토 지반에 시공되는 고강도 지오그리드 보강 쇄석말뚝(Geosynthetic-Reinforced Stone Column, GRSC)의 다양한 영향인자 검토를 통한 지지력 거동특성을 다루었다. 본 연구는 GRSC의 국내 적용을 위한 사전연구로서 대형 구조물의 기초지지 말뚝으로 적용시를 대상으로 2차원 유한요소 해석을 수행하였다. 유한요소해석 결과 GRSC와 쇄석말뚝(Stone Column, SC)의 비교를 통해 지오그리드 보강이 지지력 증가에 현저히 영향을 미치는 것으로 나타났다. 또한 지반강도와 쇄석기둥 직경, 지오그리드 강성에 대해 지지력은 증가하는 것으로 나타난 반면, 감쌈길이에 대해서는 3D(D=쇄석기둥 직경)이상의 감쌈에 대해 지지력이 수렴하는 것으로 분석되었다. 따라서 본 연구에서는 GRSC 적용시 효율적인 지오그리드 보강의 최적조건을 제안하였다.

Keywords

References

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