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

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

DOI QR Code

A numerical study on squeezing of overstressed rock around deep tunnels

심부 터널 주변 과응력 암반의 압출 거동에 관한 수치해석적 연구

  • Lee, Kun-Chai (Dept. of Natural Resources and Env. Engr., Hanyang University) ;
  • Moon, Hyun-Koo (Dept. of Natural Resources and Env. Engr., Hanyang University)
  • 이근채 (한양대학교 자원환경공학과) ;
  • 문현구 (한양대학교 자원환경공학과)
  • Received : 2016.11.03
  • Accepted : 2016.11.22
  • Published : 2016.11.30
Download PDF
⟨ Previous Next ⟩

Abstract

Squeezing is a phenomenon that may occur in deep tunneling and could bring about a large plastic deformation, tunnel closure and collapse of tunnel supports. Therefore, quantitative estimations of deformation and stress from squeezing and its possibility are necessary for establishment of a rational tunneling method. This study carried out three dimensional numerical analyses using a strain softening model in order to simulate the behaviour of squeezing and to estimate deformation and yield area around tunnels quantitatively. Numerical analyses were performed for 42 cases of various stress and strength conditions. As a result, the maximum tangential stress and strength of rock mass ratio could estimate plastic deformation and yield depth around tunnels and equations of relations between them were proposed.

심부 터널을 굴착하는 동안 발생할 수 있는 현상인 압출은 큰 소성 변형과 터널 축소 그리고 지보 붕괴를 일으킬 수 있다. 따라서 압출 현상의 발생 가능성과 변형량, 응력 변화의 정량적 예측은 합리적인 시공 방안을 수립하기 위하여 매우 중요하다. 본 연구는 변형률 연화 구성모델을 이용한 3차원 수치해석을 수행하여 압출 거동을 합리적으로 모사하고 변형량과 소성 범위 등을 정량적으로 예측하고자 하였다. 다양한 범위의 응력 조건과 강도 조건의 42가지 경우에 대한 해석을 수행한 결과 최대접선응력과 암반강도비가 소성 변형량과 소성 깊이를 합리적으로 예측할 수 있었으며 이들의 관계식을 제안하였다.

Keywords

References

  1. Amadei, B. and Stephansson, O. (1997). Rock stress and its measurement. Chapman & Hall.
  2. Aydan, O., Akagi, T., Kawamoto, T. (1993). "The Squeezing potential of rocks around tunnels; Theory and Prediction", Rock Mech. Rock Eng., Vol. 26, No. 2, pp. 137-163. https://doi.org/10.1007/BF01023620
  3. Aydan, O., Akagi, T., Kawamoto, T. (1996). "The Squeezing potential of rock around tunnels: Theory and Prediction with Examples from Japan", Rock Mech. Rock Eng., Vol. 29, No. 3, pp. 125-143. https://doi.org/10.1007/BF01032650
  4. Barla, G. (1995). "Squeezing rocks in tunnels", ISRM News J., Vol. 2, No. 3&4, pp. 44-49.
  5. Barton, N., Lien, R., Lunde, J. (1974). "Engineering classification of rock masses for the design of tunnel support", Rock Mech. Rock Eng., Vol. 6, No. 4, pp. 189-236.
  6. Brown, E.T., editor (1981). Rock characterization test and monitoring: ISRM Suggested Methods. Pergamon Press.
  7. Brown, E.T., Bray, J.W., Ladanyi, B., Hoek, E. (1983). "Ground response curves for rock tunnels", J. Geotech. Engrg., Vol. 109, No. 1, pp. 15-39. https://doi.org/10.1061/(ASCE)0733-9410(1983)109:1(15)
  8. Brown, E.T., Hoek, E. (1978). "Trends in relationships between measured in-situ stresses and depth", Int. J. Rock Mech. Min. Sci. & Geomech. Abstr., Vol. 15, No. 4, pp. 211-215. https://doi.org/10.1016/0148-9062(78)91227-5
  9. Carranza-Torres, C., Fairhurst, C. (1999). "The elastoplastic response of underground excavations in rock masses that satisfy the Hoek. Brown failure criterion", Int. J. Rock Mech. Min. Sci., Vol. 36, No. 6, pp. 777-809. https://doi.org/10.1016/S0148-9062(99)00047-9
  10. Chung, S.-K. (2003). "Stability analysis of tunnels excavated in squeezing rock masses", Tunnel and Underground Space, Vol. 13, No. 4, pp. 245-259.
  11. Cundall, P., Carranza-Torres, C., Hart, R. (2003). A new constitutive model based on the Hoek-Brown criterion. In Brummer, R. et al., editor, FLAC and Numerical Modeling in Geomechanics. 2003 (Proceedings of the 3rd International FLAC Symposium, Sudbury, Ontario, Canada, October 2003), pp. 17-26, Lisse. Balkema.
  12. Duncan Fama, M.E. (1993). Numerical modelling of yield zones in weak rocks. In Hudson, J. A., editor, Comprehensive Rock Engineering, Vol. 2, pp. 49-75. Pergamon Press.
  13. Goel, R., Jethwa, J., Paithankar, A. (1995). "Indian experiences with Q and RMR systems", Tunnelling Underground Space Technol., Vol. 10, No. 1, pp. 97-109. https://doi.org/10.1016/0886-7798(94)00069-W
  14. Hoek, E., Brown, E.T. (1980a). "Empirical strength criterion for rock masses", J. Geotech. Engrg. Div., Vol. 106, No. GT9, pp. 1013-1035.
  15. Hoek, E., Brown, E.T. (1980b). Underground Excavations in Rock. Institution of Mining and Metallurgy, London.
  16. Hoek, E., Brown, E.T. (1988). The Hoek-Brown failure criterion - a 1988 update. In Curran, J. C., editor, Proceedings of 15th Canadian Rock Mechanics Symposium, pp. 31-38, Toronto.
  17. Hoek, E., Brown, E. T. (1997). "Practical Estimates of Rock Mass Strength", Int. J. Rock Mech. Min. Sci., Vol. 34, No. 8, pp. 1165-1186. https://doi.org/10.1016/S1365-1609(97)80069-X
  18. Hoek, E., Carranza-Torres, C., Corkum, B. (2002). Hoek-Brown failure criterion. 2002 Edition. In Proceedings of NARMS-TAC Conference, pp. 267-273, Toronto.
  19. Hoek, E., Kaiser, P.K., Bawden, W.F. (1995). Support of Underground Excavations in Hard Rock. A. A. Balkema, Rotterdam.
  20. Hoek, E., Marinos, P. (2000). "Predicting tunnel squeezing problems in weak heterogeneous rock masses - part 1, part 2", Tunnels and Tunnelling International, Vol. 32, No. 11, 12, pp. 45-51, 34-36.
  21. Kovari, K., Staus, J. (1996). "Basic considerations on tunnelling in squeezing ground", Rock Mech. Rock Eng., Vol. 29, No. 4, pp. 203-210. https://doi.org/10.1007/BF01042533
  22. Lee, K.-C., Moon, H.-K. (2016). "Numerical modeling of brittle failure of the overstressed rock mass around deep tunnel", J. of Korean Tunn. Undergr. Sp. Assoc., Vol. 18, No. 5, pp. 469-485. https://doi.org/10.9711/KTAJ.2016.18.5.469
  23. Muir Wood, A.M. (1972). "Tunnels for roads and motorways", Q. J. Eng. Geol. Hydrogeol., Vol. 5, No. 1-2, pp. 111-126. https://doi.org/10.1144/GSL.QJEG.1972.005.01.12
  24. Martin, C.D., Kaiser, P.K., McCreath, D.R. (1999). "Hoek-Brown parameters for predicting the depth of brittle failure around tunnels", Canadian Geotechnical Journal, Vol. 36, pp. 136-151. https://doi.org/10.1139/t98-072
  25. Palmstrom, A. (1995). Characterizing rock burst and squeezing by the rock mass index. In International Conference in Design and Construction of Underground Structures, volume 10, New Delhi.
  26. Panet, M. (1996). "Two case histories of tunnels through squeezing rocks", Rock Mech. Rock Eng., Vol. 29, No. 3, pp. 155-164. https://doi.org/10.1007/BF01032652
  27. Park, K.-H., Kim, Y.-J. (2006). "Analytical solution for a circular opening in an elastic. brittle. plastic rock", International Journal of Rock Mechanics & Mining Sciences, Vol. 43, No. 4, pp. 616-622. https://doi.org/10.1016/j.ijrmms.2005.11.004
  28. Ramoni, M., Anagnostou, G. (2008). TBM drives in squeezing rock - Shield-rock interaction. In Building underground for the future, pp. 163-172, Montecarlo, Monaco.
  29. Schubert, W. (1996). "Dealing with squeezing conditions in alpine tunnels", Rock Mech Rock Eng, Vol. 29, No. 3, pp. 145-153. https://doi.org/10.1007/BF01032651
  30. Sharan, S.K. (2003). Elastic.brittle.plastic analysis of circular openings in Hoek. Brown media. Int. J. Rock Mech. Min. Sci., Vol. 40, No. 6, pp. 817-824. https://doi.org/10.1016/S1365-1609(03)00040-6
  31. Singh, B., Jethwa, J., Dube, A., Singh, B. (1992). "Correlation between observed support pressure and rock mass quality", Tunnelling Underground Space Technol., Vol. 7, No. 1, pp. 59-74. https://doi.org/10.1016/0886-7798(92)90114-W
  32. Steiner, W. (1996). "Tunnelling in squeezing rocks: Case histories", Rock Mech. Rock Eng., Vol. 29, No. 4, pp. 211-246. https://doi.org/10.1007/BF01042534
  33. Vrakas, A., Anagnostou, G. (2016). "Ground response to tunnel re-profiling under heavily squeezing conditions", Rock Mech. Rock Eng., Vol. 49, No. 7, pp. 2753-2762. https://doi.org/10.1007/s00603-016-0931-2
  34. Zhao, K., Janutolo, M., Barla, G. (2012). "A Completely 3D model for the simulation of mechanized tunnel excavation", Rock Mech. Rock Eng., Vol. 45, No. 4, pp. 475-497. https://doi.org/10.1007/s00603-012-0224-3