Geomechanics and Engineering

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Measures to control deformation in deep excavation for cut and cover tunneling

  • Received : 2021.12.12
  • Accepted : 2022.03.02
  • Published : 2022.05.10
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Abstract

The bored tunneling method is generally preferred for urban tunnel construction, However the cut & cover tunnel is still necessary for special conditions, such as metro station and access structures. In some case, deep excavation for cut & cover construction is planed of irregular and unusual shape, as a consequence, the convex and concave corner is often encountered during that excavation. In particular, discontinuity or imbalance of the support structure in the convex corner can lead to collapse, which may result in damages and casualties. In this study, the behavior of the convex corner of retaining structure were investigated using 3-dimensional numerical models established to be able to simulate the split-shaped behavior of convex corners. To improve the stability in the vicinity of the convex corner, several stabilizing measures were proposed and estimated numerically. It is found that linking two discretized wales at the convex corner can effectively perform the control of deformation. Furthermore, it was also confirmed that the stabilizing measures can be enhanced when the tie-material linking two discretized wales is installed at the depth of the maximum wall deflection.

Keywords

Acknowledgement

This work is supported by the Korea Agency for Infrastructure Technology Advancement(KAIA) grant funded by the Ministry of Land, Infrastructure and Transport (Research of Advanced Technology for Construction and Operation of Underground Transportation Infrastructure, Grant 22UUTI-C157786-03).

References

  1. Finno, R.J. and Roboski, J.F. (2005), "Three-dimensional response of a tied-back excavation through clay", J. Geotech. Geoenviron. Eng., 131(3), 273-282. https://doi.org/10.1061/(ASCE)1090-0241(2005)131:3(273)
  2. Finno, R.J., Blackburn, J.T. and Roboski, J.F. (2007), "Three-dimensional effects for supported excavations in clay", J. Geotech. Eng., 133(1), 30-36. https://doi.org/10.1061/(ASCE)1090-0241(2007)133:1(30).
  3. Imeni, H., Ghanbari, A., Rashidi F. and Shahir, H. (2017), "Numerical study on the effect of convex corner on the behavior of deep excavations", Elec. J. Geotech. Eng., 22(10), 3965-3984.
  4. Jeong, S.S. and Kim, Y.H. (2009), "Characteristics of collapsed retaining walls using ealsto-plastic method and finite element method", J. Kor. Geotech. Soc., 25(4), 19-29.
  5. Lee, F.H., Yong, K.Y., Quan, K.C.N. and Chee, K.T. (1998), "Effect of corners in strutted excavations: field monitoring and case histories", J. Geotech. Geoenviron. Eng., 124(4), 339-349. https://doi.org/10.1061/(ASCE)1090-0241(1998)124:4(339).
  6. Lee, S. and Kim, S.K. (2008), "A study on deformation analysis of the earth retaining wall", J. Kor. Geotech. Soc., 24(2), 27-36.
  7. Mansouri, H. and Asghari-Kaljahi. E. (2019), "Two dimensional finite element modeling of Tabriz metro underground station L2-S17 in the marly layers", Geomech. Eng., 19(4), 315-327. https://doi.org/10.12989/gae.2019.19.4.315.
  8. MIDAS (2013), GTS NX Analysis Reference.
  9. Nian, T.K., Huang, R.Q., Wan, S.S. and Chen, G.Q. (2012), "Three-dimensional strength-reduction finite element analysis of slopes: geometric effects", Can. Geotech. J., 49(5), 574-588. https://doi.org/10.1139/t2012-014.
  10. Ou, C.Y., Chiou, D. C. and Wu, T. S. (1996), "Three-dimensional finite element analysis of deep excavations", J. Geotech. Eng., 122(5), 337-345. https://doi.org/10.1061/(ASCE)0733-9410(1996)122:5(337).
  11. Ou, C.Y. (2006). Deep excavation: Theory and practice, Crc Press.
  12. Qian, J., Tong, Y., Mu, L., Lu, Q. and Zhao, H. (2020), "A displacement controlled method for evaluating ground settlement induced by excavation in clay", Geomech. Eng., 20(4), 275-285. https://doi.org/10.12989/gae.2020.20.4.275.
  13. Shin, J.H. (2015), Geomechanics and Engineering I, CIR, Seoul.
  14. Szepeshazi, A., Mahler, A. and Mozcar, B. (2016), "Three dimensional finite element analysis of deep excavations'concave corners", Per. Polytech. Civ. Eng., 60(3), 371-378. https://doi.org/10.3311/PPci.8608.
  15. Tan, Y., Wei, B., Diao, Y. and Zhou, X. (2013), "Spatial corner effects of long and narrow excavations in Shanghai soft clay", J. Perform. Const. Fac., 133(1). https://doi.org/10.1061/(ASCE)CF.1943-5509.0000475.
  16. Wei, W.B., Cheng, Y.M. and Li, L. (2009), "Three-dimensional slope failure analysis by the strength reduction and limit equilibrium method", Comp. Geotech., 36(1-2), 70-80. https://doi.org/10.1016/j.compgeo.2008.03.003.
  17. Xiang, Y., Goh, A.T.C., Zhang, W. and Zhang, R. (2018), "A multivariate adaptive regression splines model for estimation of maximum wall deflections induced by braced excavation in clays", Geomech. Eng., 14(4), 315-324. https://doi.org/10.12989/gae.2018.14.4.315.
  18. Yoo, C. (2001), "Behavior of braced and anchored walls in soils overlying rock", J. Geotech. Geoenviron. Eng., 127(3), 225-233. https://doi.org/10.1061/(ASCE)1090-0241(2001)127:3(225).
  19. Yu, Y., Damians, I.P. and Bathurst, R.J. (2015), "Influence of choice of FLAC and PLAXIS interface models on reinforced soil-structure interactions", Comput. Geotech., 65, 164-174. https://doi.org/10.1016/j.compgeo.2014.12.009.
  20. Zhang, M., Wang, X.C., Yang, G.C. and Wang, Y. (2011), "Numerical investigation of the convex effect on the behavior of crossing excavations", J. Zhejiang Univ.-Sci.A, 12(10), 747-757. https://doi.org/10.1631/jzus.A1100028.
  21. Zhang, Y., Chen, G., Wang, B. and Li, L. (2013a), "An analytical method to evaluate the effect of a turning corner on 3D slope stability", Comput. Geotech., 53, 40-45. https://doi.org/10.1016/j.compgeo.2013.05.002.
  22. Zhang, Y., Chen, G., Zheng, L., Li, Y. and Zhuang, X. (2013b), "Effects of geometries on three-dimensional slope stability", Can. Geotech. J., 50(3), 233-249. https://doi.org/10.1139/cgj2012-0279.
  23. Zhang, W., Zhang, R., Fu, Y., Goh, A.T.C. and Zhang, F. (2018), "2D and 3D numerical analysis on strut responses due to onestrut failure", Geomech. Eng, 15(4), 965-972. https://doi.org/10.12989/gae.2018.15.4.965.
  24. Zhao, W., Chen, C., Li, S. and Pang, Y. (2015), "Researches on the influence on neighboring buildings by concave and convex location effect of excavations in soft soil area", J. Intel. Rob. Syst., 79(3-4), 351-369. https://doi.org/10.1007/s10846-014-0109-7.
  25. Zheng, G., Du, Y., Cheng, X., Diao, Y., Deng, X. and Wang, F. (2017), "Characteristics and prediction methods for tunnel deformations induced by excavations", Geomech. Eng., 12(3), 361-397. https://doi.org/10.12989/gae.2017.12.3.361.
  26. Zdravkovic, L., Potts, D.M. and ST John, H.D. (2005), "Modeling of a 3D excavation in finite element analysis", Geotechnique, 55(7), 497-513. https://doi.org/10.1680/ssc.41080.0028.