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Two-dimensional Model Testing System for Analysis of PVD Installation and Soil Disturbance

PVD 설치 및 지반교란의 분석을 위한 2차원 모형실험 시스템

  • 김재현 (한국과학기술원 건설및환경공학과) ;
  • 추연욱 (한국과학기술원 건설및환경공학과) ;
  • 박현일 ((주)삼성물산 기술연구소) ;
  • 김동수 (한국과학기술원 건설및환경공학과)
  • Received : 2012.01.27
  • Accepted : 2012.04.26
  • Published : 2012.07.15

Abstract

In order to investigate the soil disturbance induced by anchor-shoe for PVD installation and the anchoring mechanism, a new two dimensional testing system was developed. By using the developed testing system, 1g and centrifuge model tests were performed, simulating the driving-retrieval process of both conventional symmetric anchor shoe and new asymmetric anchor shoe. Various size anchor-shoes were simulated and the results were compared. The images recorded during the installation were analyzed by image processing technique. The results of the image analysis presented the clay disturbance depending on the size and type of anchor shoe. In addition, from the retrieval process, the anchoring mechanism was revealed and the holding capacity was measured. As results, the size of anchor shoe influences the soil disturbance and holding capacity. The new asymmetric anchor shoe reduces the soil disturbance and improves anchoring performance.

본 논문에서는 PVD의 설치를 위하여 사용되는 앵커슈에 의한 지반교란과 정착 메커니즘을 연구하기 위하여, 맨드렐-앵커슈의 관입과정과 인발과정을 모사하고, 시각화 할 수 있는 2차원 모형실험 시스템을 개발하였다. 개발된 시스템을 활용하여, 기존 사각판형 앵커슈와 쐐기가 달린 비대칭 앵커슈의 관입과 인발 과정을 모사하는 1g 모형실험과 원심모형실험을 수행하였다. 앵커슈 크기 및 종류에 따라 지반교란과 앵커슈 정착 성능을 확인하기 위해 크기가 다른 기존 사각판형 앵커슈와 쐐기형 비대칭 앵커슈의 설치과정을 모사하였다. 관입과정에서 촬영된 영상을 이미지 분석하여, 앵커슈의 크기 및 형태에 따른 점토의 교란을 시각화하고 분석하였다. 또한, 인발과정 모사를 통하여 앵커슈의 정착 메커니즘을 밝히고 인발시 정착력을 측정하여 정착 성능을 비교하였다. 그 결과, 앵커슈의 크기는 지반교란과 인발저항력 모두에 영향을 미치며, 비대칭 앵커슈가 기존의 앵커슈에 비해 지반교란 및 배수재 정착 성능을 향상시키는 것을 확인하였다.

Keywords

References

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