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Analysis of Whole Tunnel Stability by Using Rock Mass Classification and Mohr-Coulomb Analytical Solution

암반분류와 Mohr-Coulomb 이론해를 이용한 터널 전구간 안정성 분석

  • 정용복 (한국지질자원연구원 지구환경연구본부 심지층활용연구센터 지하공간 연구팀) ;
  • 박의섭 (한국지질자원연구원 지구환경연구본부 심지층활용연구센터 지하공간 연구팀) ;
  • 류동우 (한국지질자원연구원 지구환경연구본부 심지층활용연구센터 지하공간 연구팀) ;
  • 천대성 (한국지질자원연구원 지구환경연구본부 심지층활용연구센터 지하공간 연구팀)
  • Received : 2013.07.03
  • Accepted : 2013.08.05
  • Published : 2013.08.31

Abstract

Finite element or difference methods are applied to the analysis of the tunnel stability and they provide detailed behaviour of analyzed tunnel sections but it is rather inefficient to analyze all the section of tunnel by using these methods. In this study, the authors suggest a new stability analysis method for whole tunnel to provide an efficient and easy way to understand the behaviour of whole tunnel by using an analytical solution with the assumption of equivalent circular tunnel. The mechanical behaviour, radial strain and plastic zone radius of whole tunnel were analyzed and appropriate support pressure to maintain the displacement within the allowable limit was suggested after the application of this method to the tunnel. Consequently, it was confirmed that this method can provide quick analysis of the whole tunnel stability and the quantitative information for subsequent measures such as selection of tunnel sections for detailed numerical analysis, set up of the monitoring plan, and so on.

터널의 안정성 평가방법 중 유한요소법이나 유한차분법과 같은 수치해석을 수행하면 정밀한 지반거동을 예측할 수 있으나 터널노선 전구간에 대한 수치해석은 경제적으로 비효율적이다. 따라서 본 연구에서는 이론해를 사용하고 이를 적용할 수 있도록 터널을 등가면적의 원형으로 가정하여 터널 전구간에 대한 안정성을 분석하는 방법을 제시하였다. 이를 실제 터널에 적용하여 터널 전구간에 대해 예상되는 변형거동과 정량적인 변형률 및 소성반경을 계산하였고 이로부터 변형을 적정한 수준 이내로 제한하기 위한 지보압을 제시하였다. 적용 결과 제안된 방법은 전체 터널 구간에 대한 신속한 안정성 평가와 주요 불안정 구간에 대한 정밀 해석이나 계측설계와 같은 후속조치를 위한 정량적 자료를 제공할 수 있음을 확인하였다.

Keywords

References

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