Assessment of minimum pillar width and reinforcement of parallel tunnel using numerical analysis and field monitoring

수치해석과 현장계측을 통한 병렬터널의 최소 필라폭과 보강에 대한 평가

  • An, Yong-Koan (Dept. of Geotechnical, Highcon Engineering Consultants) ;
  • Kong, Suk-Min (Dept. of Civil Engineering, Seoul National University of Science & Technology) ;
  • Lee, Yong-Joo (Dept. of Civil Engineering, Seoul National University of Science & Technology)
  • 안용관 ((주)하이콘엔지니어링) ;
  • 공석민 (서울과학기술대학교 공과대학 건설시스템공학과) ;
  • 이용주 (서울과학기술대학교 공과대학 건설시스템공학과)
  • Received : 2014.04.21
  • Accepted : 2014.05.13
  • Published : 2014.05.31


Nationally, tunnel and underground constructions are necessary for the environmental sustainability and the efficient use of land space. For the importance of eco-friendly circumstances, 2-arch or large road tunnel has been designed so far. However, such a 2-arch or large tunnel has problems in terms of cost, constructability, construction period, and maintenance. Therefore, in this study, tunnel behavior and stability of rock pillar according to the pillar width and cover depth for parallel tunnels are investigated by performing FE analysis and using empirical formula. According to the results, Rock pillar is reinforced for distributed vertical load by Tie-Bolt due to unpredicted ground deformation, and the reinforced rock pillar's behaviour from the FE analysis shows a quite good agreement with field measurement. According to ground conditions, if the pillar width of the parallel tunnels is reduced, it can be more efficient in use of the tunnel space compared to previous tunnels.


Supported by : 서울과학기술대학교


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