A study on the stability analysis for double deck tunnel branch geometry

복층터널 분기 기하구조에 따른 안정성 검토에 관한 연구

  • Park, Woo-Jeong (Geotechnical Department, Sambo Engineering Co., Ltd.) ;
  • Jang, Namju (Geotechnical Department, Sambo Engineering Co., Ltd.) ;
  • Kim, Kihwan (Geotechnical Department, Sambo Engineering Co., Ltd.) ;
  • Choi, Chang-rim (Geotechnical Department, Sambo Engineering Co., Ltd.)
  • 박우정 (삼보기술단 지반사업부) ;
  • 장남주 (삼보기술단 지반사업부) ;
  • 김기환 (삼보기술단 지반사업부) ;
  • 최창림 (삼보기술단 지반사업부)
  • Received : 2018.01.31
  • Accepted : 2018.02.27
  • Published : 2018.03.31


The tunnel can be planned to connect to underground roadway and surface road. The large tunnel and branch section are made when the ramp tunnel access to the main tunnel. In the branch section, stress concentration can be assigned and it can be very important for the stability of the tunnel. This study assessed the behavior of rock pillar in double deck tunnel diverging area by using a two dimensional numerical analysis. This study evaluated different safety factors according to pillar width and the ramp tunnel position in branch. By the assessment of the strength-stress ratio, tunnel pillar width is suggested in order to secure the safety factor 1.5.


Grant : 대심도 복층터널 설계기술 및 시공기술개발

Supported by : 국토교통과학기술진흥원


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