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An experimental study for the effect of soil plug on the basal heave stability for the vertical shaft excavation in clay

점성토 지반 수직구 굴착 중 히빙 안정성 증가에 대한 관내토 효과에 대한 실험적 연구

  • Kang, Seok-Jun (Dept. of Civil and Environmental Engineering, KAIST) ;
  • Cho, Gye-Chun (Dept. of Civil and Environmental Engineering, KAIST) ;
  • Kim, Jung-Tae (Dept. of Civil and Environmental Engineering, KAIST) ;
  • Cha, Yohan (Dept. of Civil and Environmental Engineering, KAIST) ;
  • Hong, Eun-Soo (Dept. of Civil and Environmental Engineering, KAIST)
  • Received : 2017.12.12
  • Accepted : 2018.01.03
  • Published : 2018.01.31

Abstract

Recently, the need for research on vertical shaft excavation is increasing with the increase of the demands for the underground and utility tunnels. As a part of the R&D project of the Ministry of Land, Infrastructure and Transport, CUT (center for utility tunnel) has developed "Ring cut method". "Ring cut method" is a method to improve the stability of the ground against the basal heave by excavator wall pre-penetration during vertical shaft excavation. In this study, the basal heave was simulated by centrifugal model test. The basal heave, ground subsidence, and ground deformation of surrounding ground were analyzed by soil plug effect from wall pre-penetration. It was found that the soil plug could control the basal heaving and ground subsidence, and verified that the 'Ring cut method' could be a good countermeasure for the ground stability against the basal heave.

Acknowledgement

Supported by : Ministry of Land, Infrastructure, and Transport of the Korea government

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