Using a Pressurized Shield to Increase Face Stability of Circular Tunnels in Purely Cohesive Soil
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Volume 18, Issue 9
Abstract
To obtain the critical collapse pressure of a circular tunnel driven by a pressurized shield for purely cohesive soils, a two-dimensional analysis model is presented based on limit analysis and slip-line theories. When the ratio of the cover depth C to the tunnel diameter D equals 0.5, there are three regions, Zones I, II, and III. When the C/D value is greater than 0.5, the mechanism involves up to four regions, i.e., Zones I, II, III, and possibly IV. Zone II is a transition zone that satisfies the normality condition. Zone IV is a Rankine zone subjected to the influence of the vertical soil arching effect that appears at the top of Zone III. Under Terzaghi’s theory of relative soil pressure, the contribution of Zone IV, including the weight and cohesion of the soils and the uniform surcharge loading, to the critical collapse pressure of the tunnel face is equivalent to an additional load. The proposed failure mechanism improves the existing upper-bound solutions for the face stability of circular tunnels in purely cohesive soils.
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Acknowledgments
The authors acknowledge the financial support provided by the National Natural Science Foundation of China (Grant 41572275) and the Natural Science Foundation of Shandong Province (Grant ZR2012EEM006).
References
Augarde, C. E., A. V. Lyamin, and S. W. Sloan. 2003. “Stability of an undrained plane strain heading revisited.” Comput. Geotech. 30 (5): 419–430. https://doi.org/10.1016/S0266-352X(03)00009-0.
Berthoz, N., D. Branque, D. Subrin, H. Wong, and E. Humbert. 2012. “Face failure in homogeneous and stratified soft ground: Theoretical and experimental approaches on 1g EPBS reduced scale model.” Tunnelling Underground Space Technol. 30: 25–37.https://doi.org/10.1016/j.tust.2012.01.005.
Broms, B. B., and H. Bennermark. 1967. “Stability of clay at vertical openings.” Soil Mech. Found. Eng. 93 (1): 71–94.
Chambon, P., and J.-F. Corté. 1994. “Shallow tunnels in cohesionless soil: Stability of tunnel face.” J. Geotech. Eng. 120 (7): 1148–1165. https://doi.org/10.1061/(ASCE)0733-9410(1994)120:7(1148).
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.
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.” Géotechnique 30 (4): 397–416. https://doi.org/10.1680/geot.1980.30.4.397.
Ellstein, A. R. 1986. “Heading failure of lined tunnels in soft soils.” Tunnels Tunnelling Int. 18 (6): 51–54.
Ibrahim, E., A.-H. Soubra, G. Mollon, W. Raphael, D. Dias, and A. Reda. 2015. “Three-dimensional face stability analysis of pressurized tunnels driven in a multilayered purely frictional medium.” Tunnelling Underground Space Technol. 49: 18–34. https://doi.org/10.1016/j.tust.2015.04.001.
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 clay.” In Vol. 1 of Proc., 10th Int. Conf. on Soil Mechanics and Foundation Engineering, 319–322. Rotterdam, Netherlands: Balkema.
Klar, A., A. S. Osman, and M. Bolton. 2007. “2D and 3D upper bound solutions for tunnel excavation using ‘elastic’ flow fields.” Int. J. Numer. Anal. Methods Geomech. 31 (12): 1367–1374. https://doi.org/10.1002/nag.597.
Leca, E., and L. Dormieux. 1990. “Upper and lower bound solutions for the face stability of shallow circular tunnels in frictional material.” Géotechnique 40 (4): 581–606. https://doi.org/10.1680/geot.1990.40.4.581.
Lee, C. J., B. R. Wu, H. T. Chen, and K. H. Chiang. 2006. “Tunneling stability and arching effects during tunneling in soft clayey soil.” Tunnelling Underground Space Technol. 21 (2): 119–132. https://doi.org/10.1016/j.tust.2005.06.003.
Chen, W.-F., ed. 1975. Limit analysis and soil plasticity. Amsterdam, Netherlands: Elsevier.
Mollon, G., D. Dias, and A.-H. Soubra. 2009. “Probabilistic analysis and design of circular tunnels against face stability.” Int. J. Geomech. 9 (6): 237–249. https://doi.org/10.1061/(ASCE)1532-3641(2009)9:6(237).
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. 2011. “Rotational failure mechanisms for the face stability analysis of tunnels driven by a pressurized shield.” Int. J. Numer. Anal. Methods Geomech. 35 (12): 1363–1388. https://doi.org/10.1002/nag.962.
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.
Schofield, A. N. 1980. “Cambridge geotechnical centrifuge operations.” Géotechnique 30 (3): 227–268. https://doi.org/10.1680/geot.1980.30.3.227.
Zhang, C., K. Han, and D. 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.
Information & Authors
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Published In
International Journal of Geomechanics
Volume 18 • Issue 9 • September 2018
Copyright
© 2018 American Society of Civil Engineers.
History
Received: Jun 23, 2017
Accepted: Feb 2, 2018
Published online: Jun 22, 2018
Published in print: Sep 1, 2018
Discussion open until: Nov 22, 2018
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