Journal of Korean Tunnelling and Underground Space Association (한국터널지하공간학회 논문집)

Korean Tunnelling and Underground Space Association (한국터널지하공간학회)
권호 표지
DOI QR코드

DOI QR Code

Influence analysis of continuous pile walls on the behavior of a soil tunnel at the shallow depth through a parametric study

민감도 분석을 통한 주열식벽체가 저토피 토사터널 거동에 미치는 영향 분석

  • 유광호 (수원대학교 토목공학과) ;
  • 윤우진 (수원대학교 토목공학과)
  • Received : 2014.01.09
  • Accepted : 2014.01.24
  • Published : 2014.01.29
Download PDF
⟨ Previous Next ⟩

Abstract

In recent years, utilization of underground space has been increasing in various parts of the world. In particular, open-cut method is usually applied to the shallow depth excavation. However some problems such as extreme traffic congestion and unstability of adjacent structures etc. might occur. In order to cope with these problems, the M-CAM (Modified Cellular Arch Method) method was proposed to excavate soil tunnels at shallow depth with secured enough stability and minimized construction period. In this study, sensitivity analysis was performed to predict the influence of the size of CPW(Continuous Pile Wall) and ground conditions on the behavior of the tunnel. First of all, embedded depth and diameter (or thickness) of CPW, coefficient of lateral earth pressure, and ground conditions were selected as parameters that could affect tunnel stability. Meanwhile, FLAC 2D based on finite difference method was used for numerical analysis. As a result of this study, it was checked out that embedded depth among sizes of CPW had a greatest influence on the stability of a tunnel.

최근 세계 여러 나라에서는 지하공간의 활용이 증가하고 있다. 특히, 저심도 굴착의 경우 대부분 개착식 굴착공법을 적용하는데, 극심한 교통 체증 및 인접구조물의 불안정 등의 문제가 발생될 수도 있다. 이러한 문제를 극복하기 위해서 저토피 토사구간에서 충분한 안정성을 확보하고 공사기간을 최소화하며 터널을 굴착할 수 있는 M-CAM공법(Modified Cellular Arch Method)이 제안되었다. 본 연구에서는 M-CAM공법 적용 시 주열식 수직연속벽체(Continuous Pile Wall, CPW)의 규격 및 지반조건이 터널 거동에 미치는 영향을 파악하기 위해 민감도분석을 수행하였다. 우선 터널의 안정성에 영향을 주는 매개변수로는 수직연속벽체의 근입깊이, 직경, 측압계수 그리고 지반상태를 선정하였다. 한편 수치해석을 위해서, 유한차분법에 기초를 둔 FLAC 2D가 이용되었다. 본 연구결과 수직연속벽체의 규격 중 근입깊이가 터널 안정성에 가장 큰 영향을 주는 것을 확인되었다.

Keywords

References

  1. Bishop, A.W. (1955), "The use of pore pressure coefficient in practice", Geotechnique, Vol. 5, pp. 7-17.
  2. Dawson, E.M., Roth, W.H., Drescher, A. (1999), "Slope stability analysis by strength reduction", Geotechnique, Vol. 49, pp. 835-840. https://doi.org/10.1680/geot.1999.49.6.835
  3. Duncan, J.M. (1996), "State of the art : limit equilibrium and finite element analysis of slopes", Journal of Geotechnical Engineering, Vol. 122, pp. 577-596. https://doi.org/10.1061/(ASCE)0733-9410(1996)122:7(577)
  4. Itasca Consulting Group, Inc. (2005), Fast Lagrangian Analysis of Continua, Ver. 5.0, Itasca Consulting Group, Minnesota, USA.
  5. Kim, U.J., Sohn, Y.J., Cho, H., Lim, J.S. (2010), "Tunnel design of using M-CAM method", Korean Society of Civil Engineers Conference, pp. 1748-1751.
  6. Lim, J.S., Choi, J.H., J, H. (2011), "Tunneling method of using continuous pile wall at shallow depth", Journal of the Korea Association of Geotechnical Professional Engineers, Vol. 8, No. 1, pp. 3-10.
  7. You, K.H., Park, Y.J., Bae, G.J. (2000), "An assessment of safety factor for tunnels excavated in a weak rock layer", Journal of the Korean Tunnelling Association, Vol. 2, No. 3, pp. 47-57.
  8. You, K.H., Park, Y.J., Kang, Y. (2001), "A numerical study on the estimation of safety factor of tunnels excavated in jointed rock mass", Journal of the Korean Society for Rock Mech., Vol. 11, No. 3, pp. 279-288.
  9. You, K.H., Park, Y.J., Hong, K.Y., Lee, H.K., Kim, J.K. (2005), "Numerical estimation for safety factors of tunnels considering the failure of supports", Journal of the Korean Tunnelling Association, Vol. 7, No. 1, pp. 37-48.
  10. You, K.H., Yoon, W.J., Park, G.S., Cho, H., Lim, J.S. (2013), "A study on the stability of M-CAM construction method using finite difference method", Korean Society of Civil Engineers Conference, pp. 950-953.