An Assessment of Rock Pillar Stability in Tunnel Asymmetric Diverging Area using the Mohr-Coulomb Failure Theory

Choul-Kyu Lee; Kang-Il Lee; Jae-Gi Kang

doi:10.12814/jkgss.2016.15.4.017

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2016 Vol.15, Issue 4 Preview Page Next Page

An Assessment of Rock Pillar Stability in Tunnel Asymmetric Diverging Area using the Mohr-Coulomb Failure Theory Mohr-Coulomb 파괴접근도 방법을 이용한 비대칭 분기부 암반필러의 안정성 평가

30 December 2016. pp. 17-23

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Abstract

This study assessed the behavior of rock pillar in tunnel asymmetric diverging area by using a three dimensional numerical analysis. The stability of pillar is very important for the ensure the stability of the tunnel asymmetric diverging area. Based on parameters affecting the behavior of rock pillar, this study evaluated different safety factors according to pillar width, depth and rock conditions. It turned out that as the rock pillar width increases, the change curve of safety factors in accordance with depth and rock conditions shows more of the nonlinear behavior. By the assessment of the minimum safety factor, a safety factor chart on the behavior of rock pillar in tunnel asymmetric diverging area was suggested.

Keywords

Tunnel asymmetric diverging area

Rock pillar

Numerical analysis

Safety factor chart

본 연구에서는 터널을 대상으로 비대칭 분기부 암반 필러의 거동을 3차원 수치해석 방법으로 검토하였다. 터널 비대칭 분기부의 경우 필러부의 안정성을 확보하는 것이 본 터널의 안정성을 좌우하는 매우 중요한 요소라 할 수 있다. 암반 필러의 거동에 영향을 미치는 매개변수로 암반 필러의 이격거리, 토피고, 암반등급 변화에 따른 안전율을 평가하였다. 터널 비대칭 분기부 암반 필러의 이격거리가 증가할수록 토피고와 암반등급에 따른 안전율 변화 곡선은 비선형 거동을 보였으며, 터널 비대칭 분기부에서 암반 필러의 거동 특성을 최소 안전율을 기준으로 안전율 도표로서 제안하였다.

References

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Information

Publisher :Korean Geosythetics Society
Publisher(Ko) :한국지반신소재학회
Journal Title :Journal of the Korean Geosynthetics Society
Journal Title(Ko) :한국지반신소재학회 논문집
Volume : 15
No :4
Pages :17-23
Received Date : 2016-10-05
Revised Date : 2016-11-12
Accepted Date : 2016-11-25
DOI :https://doi.org/10.12814/jkgss.2016.15.4.017

Journal of the Korean Geosynthetics Society ISSN:2508-2876(Print) 2287-9528(Online) 한국지반신소재학회 논문집

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