Analysis of the Collapse Mechanism and Stabilization Optimization of the Composite Stratum at the Boundary between Prereinforced and Unreinforced Areas near a Shield Launching Area
Publication: International Journal of Geomechanics
Volume 23, Issue 5
Abstract
Grouting reinforcement methods are usually employed in shield launching sections due to shallow burial depths and poor stratigraphic conditions. Hence, grouting reinforcement provides an increase in buried depth and better formation conditions. The length of prereinforcement is often determined by engineering experience. Excessive ground settlement, collapse, and even buried machine accidents may occur when shield tunneling occurs at the boundary between prereinforced and unreinforced areas. The case of the collapse of the composite stratum at the boundary between prereinforced and unreinforced areas near the shield launching area of the Shumuling shield tunnel in Changsha was analyzed in combination with monitoring data around the collapse area. Based on the slip-line theory and limit analysis method, the evolution pattern instability of the tunnel face soils around the collapse area was analyzed by means of FLAC3D5.0. This model provides a failure mechanism used to analyze the stability of the tunnel face of a shallow circular shield tunneling through the composite stratum at the boundary between prereinforced and unreinforced areas. The limit-supporting force that maintains the stability of the tunnel face was calculated. The rationale behind the proposed failure mechanism was validated by comparing the calculated value of the limit-supporting force with the monitoring value in the chamber of the earth press balance shield machine (EPB). Based on the proposed failure mechanism and considering the influence of the surrounding environment (nearby railroad), a reasonable reinforcement method was selected, and the design reinforcement scheme for the soil in the collapse area was optimized. The research results are expected to provide useful guidance for the stability analysis and safe construction of shield excavation at the boundary between prereinforced and unreinforced areas near shield launching areas.
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Data Availability Statement
All codes written in FLAC that support the findings of this study are available from the corresponding author upon reasonable request.
This work was supported by the Natural Science Foundation of Shandong Province (Grant Number ZR2021ME135).
References
Ads, A., M. Shariful Islam, and M. Iskander. 2021. “Effect of face losses and cover-to-diameter ratio on tunneling induced settlements in soft clay, using transparent soil models.” Geotech. Geol. Eng. 39: 5529–5547. https://doi.org/10.1007/s10706-021-01843-7.
Alagha, A., and D. N. Chapman. 2019. “Numerical modelling of tunnel face stability in homogeneous and layered soft ground.” Tunnelling Underground Space Technol. 94: 103096. https://doi.org/10.1016/j.tust.2019.103096.
Anagnostou, G., and K. Kovari. 1996. “Face stability conditions with earth-pressure-balanced shields.” Tunnelling Underground Space Technol. 11 (2): 165–173. https://doi.org/10.1016/0886-7798(96)00017-X.
Broere, W. 2001. Tunnel face stability and new CPT applications. Delft, Netherlands: Delft Univ.
Broms, B. B., and H. Bennermark. 1967. “Stability of clay at vertical openings.” J. Soil Mech. Found. Div. 93: 71–94.
Chen, R. P., J. Li, L. G. Kong, and L. J. Tang. 2013. “Experimental study on face instability of shield tunnel in sand.” Tunnelling Underground Space Technol. 33: 12–21. https://doi.org/10.1016/j.tust.2012.08.001.
Chen, R. P., L. J. Tang, D. S. Ling, and Y. M. Chen. 2011. “Face stability analysis of shallow shield tunnels in dry sandy ground using the discrete element method.” Comput. Geotech. 38 (2): 187–195. https://doi.org/10.1016/j.compgeo.2010.11.003.
Cheng, C., P. J. Jia, W. Zhao, P. P. Ni, Q. Bai, Z. J. Wang, and B. Lu. 2021. “Experimental and analytical study of shield tunnel face in dense sand strata considering different longitudinal inclination.” Tunnelling Underground Space Technol. 113: 103950. https://doi.org/10.1016/j.tust.2021.103950.
Davis, E. H., M. J. Gunn, R. J. Mair, and H. N. Seneviratne. 1980. “The stability of shallow tunnels and underground openings in cohesive material.” Geotechnique 30 (4): 397–416. https://doi.org/10.1680/geot.1980.30.4.397.
Ding, W. T., K. Q. Liu, P. H. Shi, M. J. Li, and M. L. Hou. 2019. “Face stability analysis of shallow circular tunnels driven by a pressurized shield in purely cohesive soils under undrained conditions.” Comput. Geotech. 107: 110–127. https://doi.org/10.1016/j.compgeo.2018.11.025.
Ellstein, A. R. 1986. “Heading failure of lined tunnels in soft soils.” Tunnels Tunnelling Int. 18 (6): 51–54.
Fernandez, F., J. E. G. Rojas, E. A. Vargas, R. Q. Velloso, and D. Dias. 2021. “Three-dimensional face stability analysis of shallow tunnels using numerical limit analysis and material point method.” Tunnelling Underground Space Technol. 112: 103904. https://doi.org/10.1016/j.tust.2021.103904.
Gong, X. N. 1990. Soil plastic mechanics. Hangzhou, China: Zhejiang University Press.
Horn, M. 1961. “Horizontal earth pressure on perpendicular tunnel face.” In Proc., Hungarian National Conf. of the Foundation Engineer Industry, 7–16. Budapest, Hungary: Hungary Press.
Hu, X. Y., W. Fu, S. Z. Wu, Y. Fang, and C. He. 2021. “Numerical study on the tunnel stability in granular soil using dem virtual air bag model.” Acta Geotech. 16: 3285–3300. https://doi.org/10.1007/s11440-020-01130-4.
Huang, M. S., S. Li, J. Yu, and J. Q. W. Tan. 2018. “Continuous field based upper bound analysis for three-dimensional tunnel face stability in undrained clay.” Comput. Geotech. 94: 207–213. https://doi.org/10.1016/j.compgeo.2017.09.014.
Idinger, G., P. Aklik, W. Wu, and R. I. Borja. 2011. “Centrifuge model test on the face stability of shallow tunnel.” Acta Geotech. 6 (2): 105–117. https://doi.org/10.1007/s11440-011-0139-2.
Kimura, T., and R. J. Mair. 1981. “Centrifugal testing of model tunnels in soft soil.” In Proc., 10th Int. Conf. on Soil Mechanics and Foundation Engineering, 319–322. Rotterdam, Netherlands: Balkema.
Leca, E., and L. Dormieux. 1990. “Upper and lower bound solutions for the face stability of shallow circular tunnels in frictional material.” Geotechnique 40 (4): 581–606. https://doi.org/10.1680/geot.1990.40.4.581.
Li, W., C. P. Zhang, Z. B. Tan, and M. S. Ma. 2021. “Effect of the seepage flow on the face stability of a shield tunnel.” Tunnelling Underground Space Technol. 112 (4): 103900. https://doi.org/10.1016/j.tust.2021.103900.
Li, Z., X. L. Yang, and T. Li. 2019. “Face stability analysis of tunnels under steady unsaturated seepage conditions.” Tunnelling Underground Space Technol. 93: 103095. https://doi.org/10.1016/j.tust.2019.103095.
Liu, K. Q., D. Dias, W. T. Ding, and R. Chen. 2021. “Influence of soil-arching effect on tunnel face stability.” Int. J. Geomech. 21 (7): 04021107. https://doi.org/10.1061/(ASCE)GM.1943-5622.0002060.
Mollon, G., D. Dias, and A. H. Soubra. 2010. “Face stability analysis of circular tunnels driven by a pressurized shield.” J. Geotech. Geoenviron. Eng. 136 (1): 215–229. https://doi.org/10.1061/(ASCE)GT.1943-5606.0000194.
Mollon, G., D. Dias, and A. H. Soubra. 2013. “Continuous velocity fields for collapse and blowout of a pressurized tunnel face in purely cohesive soil.” Int. J. Numer. Anal. Methods Geomech. 37 (13): 2061–2083. https://doi.org/10.1002/nag.2121.
Sagaseta, C. 1988. “Discussion: Analysis of undrained soil deformation due to ground loss.” Geotechnique 38 (4): 647–649. https://doi.org/10.1680/geot.1988.38.4.647.
Senent, S., and R. Jimenez. 2015. “A tunnel face failure mechanism for layered ground, considering the possibility of partial collapse.” Tunnelling Underground Space Technol. 47: 182–192. https://doi.org/10.1016/j.tust.2014.12.014.
Uriel, A. O., and C. Sagaseta. 1989. “Selection of parameters for underground construction.” In Vol. 4 of Proc., XIIth Int. Conf. on Soil Mechanics and Foundation Engineering, 2521–2551. Rotterdam, Netherlands: Balkema.
Verruijt, A. 1997. “A complex variable solution for a deforming circular tunnel in an elastic half-plane.” Int. J. Numer. Anal. Methods Geomech. 21: 77–89. https://doi.org/10.1002/(SICI)1096-9853(199702)21:2%3C77::AID-NAG857%3E3.0.CO;2-M.
Yin, X. S., R. P. Chen, and F. Y. Meng. 2021a. “Influence of seepage and tunnel face opening on face support pressure of EPB shield.” Comput. Geotech. 135: 104198. https://doi.org/10.1016/j.compgeo.2021.104198.
Yin, X. S., R. P. Chen, F. Y. Meng, Z. Ding, and M. A. Mooney. 2021b. “Face stability of slurry-driven shield with permeable filter cake.” Tunnelling Underground Space Technol. 111 (111): 103841. https://doi.org/10.1016/j.tust.2021.103841.
Zhang, C. P., K. H. Han, and D. L. Zhang. 2015. “Face stability analysis of shallow circular tunnels in cohesive–frictional soils.” Tunnelling Underground Space Technol. 50: 345–357. https://doi.org/10.1016/j.tust.2015.08.007.
Zhang, F., Y. F. Gao, Y. X. Wu, and N. Zhang. 2019. “Upper-bound solutions for face stability of circular tunnels in undrained clays.” Geotechnique 69 (1): 655–658. https://doi.org/10.1680/jgeot.18.d.003.
Zhang, Y. P., S. C. Wu, and Z. L. Fang. 2004. “Property analysis of rock and soil masses properties after cement-grouting.” J. Beijing Univ. Sci. Technol. 3: 16–19. https://doi.org/10.3321/j.issn:1001-053X.2004.03.004.
Zhang, Z. X., X. Y. Hu, and K. D. Scott. 2011. “A discrete numerical approach for modeling face stability in slurry shield tunnelling in soft soils.” Comput. Geotech. 38 (1): 94–104. https://doi.org/10.1016/j.compgeo.2010.10.011.
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Published In
International Journal of Geomechanics
Volume 23 • Issue 5 • May 2023
Copyright
© 2023 American Society of Civil Engineers.
History
Received: Jun 26, 2022
Accepted: Oct 22, 2022
Published online: Feb 22, 2023
Published in print: May 1, 2023
Discussion open until: Jul 22, 2023
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