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Short- and Long-term Load Carrying Capacity of Geogrid-encased Stone Column - A numerical investigation

지오그리드 감쌈 쇄석기둥 공법의 장.단기 하중 지지 특성 - 유한요소해석을 통한 고찰

  • Lee, Dae-Young (Department of Geotechnical Engrg., Korea Institue of Construction Technology) ;
  • Song, Ah-Ran (Dept. of Civil & Environ. Engrg., Sungkyunkwan Univ.) ;
  • Kim, Sun-Bin (Dept. of Civil & Environ. Engrg., Sungkyunkwan Univ.) ;
  • Yoo, Chung-Sik (Dept. of Civil & Environ. Engrg., Sungkyunkwan Univ.)
  • 이대영 (한국건설기술연구원) ;
  • 소아란 (성균관대학교 토목환경공학과) ;
  • 김선빈 (성균관대학교 토목환경공학과) ;
  • 유충식 (성균관대학교 토목환경공학과)
  • Published : 2007.08.31

Abstract

The stone column method is widely used in Europe as an alternative to conventional pile foundations. Several benefits of using the stone column method include sound performance, low cost, expediency of construction, and liquefaction resistance among others. Recently, geosynthetic-encased stone column approach has been developed to improve its load carrying capacity through increasing confinement effect. Although such a concept has been successfully applied in practice, fundamentals of the method have not been fully explored. This paper presents the results of an investigation on the load carrying capacity of geogrid-encased stone column using a series of 2D finite element analyses. A parametric study was then conducted for influencing factors such as effect of geogrid encasement, encasement length, geogrid strength, among others. The results of the analyses indicated improved short- and long-term load carrying capacity of the geogrid-encased stone column method has advantages over the conventional stone column method without encasing.

유럽 등지에서 연약지반 개량 또는 제방기초로서 적용되는 쇄석기둥 공법은 일반적인 파일기초의 대안공법으로 경제성 및 시공성 측면에서 효율적이며, 액상화 방지에도 효과가 있는 것으로 알려져 있다. 또한 최근 들어서는 더욱 발전된 형태의 지오그리드 보강 쇄석기둥 공법에 관한 연구가 활발히 진행되고 있는 실정이다. 이와 관련하여 본 논문에서는 지오그리드 보강 쇄석기둥 공법의 성토하중에 대한 쇄석기둥의 하중지지 특성을 고찰하기 위해 2차원 유한요소해석을 수행하였고, 지오그리드 보강효과, 지오그리드 강성, 지오그리드 감쌈깊이 등 영향인자에 대한 매개변수 연구를 수행하였다. 해석결과로부터 지오그리드 보강은 쇄석기둥 공법의 장 단기 하중지지 특성 개선시켜 주는 것으로 나타났다.

Keywords

References

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