Geomechanics and Engineering

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Infiltration characteristic of modified slurry and support efficiency of filter cake in silty sand strata

  • Sai Zhang (Department of Underground Engineering, Southeast University) ;
  • Jianwen Ding (Department of Underground Engineering, Southeast University) ;
  • Ning Jiao (Department of Underground Engineering, Southeast University) ;
  • Shuai Sun (Department of Underground Engineering, Southeast University) ;
  • Jinyu Liu (Department of Underground Engineering, Southeast University)
  • Received : 2022.08.08
  • Accepted : 2023.04.18
  • Published : 2023.07.25
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Abstract

To improve the understanding of infiltration characteristic of modified slurry and the support efficiency of filter cake in silty sand strata, the slurry infiltration (SI) and filter cake formation (FCF) were investigated in a laboratory apparatus. The water discharge and the excess pore pressure at different depths of silty sand strata were measured during SI. The relationship between permeability coefficient/thickness ratio of filter cake (kc/ΔL) and effective slurry pressure conversion rate of filter cake (η) were analyzed. Moreover, the SI and FCF process as well as the modification mechanism of CMC (carboxymethyl cellulose) were clarified. The experimental results indicate the formation of only external filter cake in the silty sand strata. The slurry particles obtain thicker water membrane after being modified by CMC, which blocks partial water path in filter cake and decreases the water discharge significantly. The silty sand excavated from tunnel face also contributes to the water discharge reduction. The kc of the external filter cake ranges from 3.83×10-8 cm/s to 7.44×10-8 cm/s. The η of the external filter cake is over 96%, which decreases with increasing kc/ΔL. A silty sand content within 10% is suggested during construction to ensure the uniformity of the filter cake.

Keywords

Acknowledgement

This study is partially supported by the National Natural Science Foundation of China (Grant No. 51978159), National Key R&D Program of China (Grant No. 2015BAB07B06).

References

  1. Anagnostou, G. and Kovari, K. (1994), "The face stability of slurry-shield-driven tunnels", Tunn. Undergr. Sp. Tech., 9(2), 165-174. https://doi.org/10.1016/0886-7798(94)90028-0.
  2. ASTM (American Society for Testing and Materials) (2006), Standard test method for permeability of granular soils (constant head). ASTM D2434-06. ASTM, West Conshohocken, PA, USA.
  3. ASTM (American Society for Testing and Materials) (2007), Standard test method for particle-size analysis of soils. ASTM D422, West Conshohocken, PA, USA.
  4. Aydin, A., Ozbek, A. and Cobanoglu, I. (2004), "Tunnelling in difficult ground: a case study from dranaz tunnel, sinop, turkey", Eng. Geol., 74(3), 293-301. https://doi.org/10.1016/j.enggeo.2004.04.003.
  5. Bezuijen, A., Pruiksma, J.P. and van Meerten, H.H. (2006), Pore Pressures in front of Tunnel, Measurements, Calculations and Consequences for Stability of Tunnel Face. In Tunnelling. A Decade of Progress. GeoDelft 1995-2005 (Eds., A. Bezuijen and H. van Lottum), 35-41. Leiden, the Netherlands: Taylor & Francis (Balkema).
  6. Braga, M., Pato, M., Silva, H., Ferreira, E.I., Gil, M.H. and Duarte, C. (2008), "Supercritical solvent impregnation of ophthalmic drugs on chitosan derivatives", J. Supercritical Fluid., 44(2), 245-257. https://doi.org/10.1016/j.supflu.2007.10.002.
  7. Broere, W. (2001), "Tunnel face stability & new CPT application", PhD Dissertation. Delft University of Technology, Delft, Netherlands.
  8. Broere, W. (2016), "Urban underground space: solving the problems of today's cities", Tunn. Undergr. Sp. Tech., 55, 245-248. https://doi.org/10.1016/j.tust.2015.11.012.
  9. Duong, T.V., Trinh, V.N., Cui, Y.J., Tang, A.M. and Calon, N. (2013), "Development of a large-scale infiltration column for studying the permeability of unsaturated fouled ballast", Geotech. Test. J., 36, 1-10. https://doi.org/10.1520/GTJ20120099.
  10. Dixon, D.A., Gray, M.N. and Thomas, A.W. (1985), "A study of the compaction properties of potential clay-sand buffer mixtures for use in nuclear fuel waste disposal", Eng. Geol., 21, 247-255. https://doi.org/10.1016/0013-7952(85)90015-8.
  11. Fritz, P., Stengele, R.H. and Heinz, A. (2002), "Modified bentonite slurries for slurry shields in highly permeable soils", Proceedings of the 4rth International Symposium Geotechnical Aspects of Underground Construction in Soft Ground, Toulouse, France.
  12. Fritz, P. (2007), "Additives for slurry shields in highly permeable ground", Rock Mech. Rock Eng., 40(1), 81-95. https://doi.org/10.1007/s00603-006-0090-y.
  13. Hu, X.Y. and Zhang, Z.X. (2009), "Analysis of effect of slurry infiltration on shear strength of soil of excavation face in slurry shield under general stress condition", Chinese J. Rock Mech. Eng., 28(5), 1027-1036. (In Chinese).
  14. Lee, I.M., Nam, S.W. and Ahn, J.H. (2003), "Effect of seepage forces on tunnel face stability", Can. Geotech. J., 40(2), 342-350. https://doi.org/10.1139/t02-120.
  15. Li, X. and Yuan, D. (2018), "Creating a working space for modifying and maintaining the cutterhead of a large-diameter slurry shield: a case study of Beijing railway tunnel construction", Tunn. Undergr. Sp. Tech., 72, 73-83. https://doi.org/10.1016/j.tust.2017.11.008.
  16. Lin, C.G., Zhang, Z.M., Wu, S.M. and Yu, F. (2013), "Key techniques and important issues for slurry shield under-passing embankments: a case study of Hangzhou Qiantang river tunnel", Tunn. Undergr. Sp. Tech., 38(9), 306-325. https://doi.org/10.1016/j.tust.2013.07.004.
  17. Lin, Y., Fang, Y., He, C. and Wang, W. (2021), "Experimental study on degree of match between slurry and ground based on particle retention rate", Tunn. Undergr. Sp. Tech., https://doi.org/10.1016/j.tust.2021.104105.
  18. Liu, P.F., Wang, S.Y., Ge, L., Thewes, M., Yang, J.S. and Xia, Y.M. (2018), "Changes of atterberg limits and electrochemical behaviors of clays with dispersants as conditioning agents for EPB shield tunnelling", Tunn. Undergr. Sp. Tech., 73, 244-251. https://doi.org/10.1016/j.tust.2017.12.026.
  19. Lloret, A., Villar, M.V., Sa'nchez, M., Gens, A., Pintado, X. and Alonso, E.E. (2003). "Mechanical behaviour of heavily compacted bentonite under high suction changes", Geotechnique, 53(1), 27-40. https://doi.org/10.1680/geot.53.1.27.37258.
  20. Mao, J., Yuan, D., Jin, D., Wang, B. and Wu, S. (2021), "Experimental study on electrical resistivity characteristics of saturated sand mixes with bentonite slurry", Appl. Sci., 11, 12126. https://doi.org/10.3390/app112412126.
  21. Min, F.L. (2012), "Laws of slurry infiltration in soils and filter cake formation in slurry type shield", PhD Dissertation, college of environment, HoHai University, Nanjing, P.R. China (in Chinese).
  22. Min, F.L., Zhu,W. and Han, X.R. (2013), "Filter cake formation for slurry shield tunneling in highly permeable sand", Tunn. Undergr. Sp. Tech., 38, 423-430. https://doi.org/10.1016/j.tust.2013.07.024.
  23. Min, F.L., Zhu,W., Lin, C. and Guo, X. (2015), "Opening the excavation chamber of the large-diameter size slurry shield: a case study in Nanjing Yangtze river tunnel in China", Tunn. Undergr. Sp. Tech., 46, 18-27. https://doi.org/10.1016/j.tust.2014.10.002.
  24. Min, F.L., Song, H. and Zhang, N. (2018), "Experimental study on fluid properties of slurry and its influence on slurry infiltration in sand stratum", Appl, Clay Sci,, 161, 64-69. https://doi.org/10.1016/j.clay.2018.03.028.
  25. Min, F.L., Du, J.R. and Zhang, N. (2019), "Experimental study on property change of slurry and filter cake of slurry shield under seawater intrusion", Tunn. Undergr. Sp. Tech., 88, 290-299. https://doi.org/10.1016/j.tust.2019.03.006.
  26. Ni, L.A., Yu, A.B., Lu, G.Q. and Howes, T. (2006), "Simulation of the cake formation and growth in cake filtration", Miner. Eng., 19(10), 1084-1097. https://doi.org/10.1016/j.mineng.2006.03.012.
  27. Park, J.K. (2022), "Reliability analysis of tunnel face stability considering seepage effects and strength conditions", Geomech. Eng., 29(3), 331-338. https://doi.org/10.12989/gae.2022.29.3.331.
  28. Ray, S.S. and Bousmina, M. (2005), "Biodegradable polymers and their layered silicate nanocomposites: In greening the 21st century materials world", Progress Mater. Sci., 50(8), 962-1079. https://doi.org/10.1016/j.pmatsci.2005.05.002.
  29. Sherard, J.L., Dunnigan, L.P. and Talbot, J.R. (1984), "Basic properties of sand and gravel filters", J. Geotech. Eng., 110(6), 684-700. https://doi.org/10.1061/(ASCE)0733-9410(1984)110:6(684).
  30. Stutzmann, T. and Siffert, B. (1977), "Contribution to the adsorption mechanism of acetamide and polyacrylamide on to clays". Clays Clay Miner., 25(6), 392-406. https://doi.org/10.1346/CCMN.1977.0250604.
  31. Tien, Y.I.. and Wei, K.H. (2001), "Hydrogen bonding and mechanical properties in segmented montmorillonite/polyurethane nanocomposites of different hard segment ratios", Polymer, 42(7), 3213-3221. https://doi.org/10.1016/S0032-3861(00)00729-1.
  32. Talmon, A.M., Mastbergen, D.R. and Huisman, M. (2013), "Invasion of pressurized clay suspensions into granular soil", J. Porous Media, 16, 351-365. https://doi:10.1615/JPorMedia.v16.i4.70.
  33. Wang, S.W., Zhu, W., Fei, K., Xu, C.Y. and Zhang, N. (2018), "Study on non-darcian flow sand clay mixtures", Appl. Clay Sci., 151, 102-108. https://doi.org/10.1016/j.clay.2017.10.028.
  34. Wei, C., Liu, D., Song H.F., Zhang, S.R. and He, S.W. (2020), "Experimental study of salt-resisting slurry for undersea shield tunnelling", Tunn. Undergr. Sp. Tech., 98, 103322. https://doi.org/10.1016/j.tust.2020.103322.
  35. Wu, T., Wang, Z., Wang, H., Zhang, Z. and Van Loon, L.R. (2017), "Salt effects on Re(VII) and Se(IV) diffusion in bentonite". Appl. Clay Sci., 141, 104-110. https://doi.org/10.1016/j.clay.2017.02.021.
  36. Xu, T. and Bezuijen, A. (2018), "Bentonite slurry infiltration into sand, filter cake formation under various conditions", Geotechnique, 69(12), 1095-1106. https://doi.org/10.1680/jgeot.18.P.094.
  37. Xu, T. and Bezuijen, A. (2019), "Experimental study on the mechanisms of bentonite slurry penetration in front of a slurry TBM", Tunn. Undergr. Sp. Tech., 93, 1-10. https://doi.org/10.1016/j.tust.2019.103052.
  38. Zhang, L., Sun, D. and Jia, D. (2016), "Shear strength of GMZ07 bentonite and its mixture with sand saturated with saline solution", Appl. Clay Sci., 132-133, 24-32. https://doi.org/10.1016/j.clay.2016.08.004.
  39. Zhang, N., Yu, X.B., Pradhan, A. and Puppala, A.J. (2017), "A new generalized soil thermal conductivity model for sand-kaolin clay mixtures using thermo-time domain reflectometry probe test", Acta Geotechnica, 12(4), 739-752. https://doi.org/10.1007/s11440-016-0506-0.
  40. Zhao, J., Gong, Q.M. and Eisensten, Z. (2007), "Tunnelling through a frequently changing and mixed ground: a case history in Singapore", Tunn. Undergr. Sp. Tech., 22(4), 388-400. https://doi.org/10.1016/j.tust.2006.10.002.
  41. Zizka, Z., Schoesser, B., Thewes, M. and Schanz, T. (2018), "Slurry shield tunneling: new methodology for simplified prediction of increased pore pressures resulting from slurry infiltration at the tunnel face under cyclic excavation processes", Inte. J. Civil Eng., 15(4), 387-405. https://doi.org/10.1007/s40999-018-0303-2.
  42. Zizka, Z. and Thewes, M. (2016), Recommendations for Face Support Pressure Calculations for Shield Tunnelling in Soft Ground. In Deutscher Ausschuss fur unterirdisches Bauen e. V. (DAUB) - German Tunnelling Committee (ITA-AITES).
  43. Zizka, Z., Schoesser, B. and Thewes, M. (2021), "Investigations on the transient support pressure transfer at the tunnel face during slurry shield drive Part 2: Case B - Deep slurry penetration exceeds tool cutting depth", Tunn. Undergr. Sp. Tech., 118, 104196. https://doi.org/10.1016/j.tust.2021.104169.
  44. Zhang, N., Yu, X.B., Pradhan, A. and Puppala, A.J. (2017), "A new generalized soil thermal conductivity model for sand-kaolin clay mixtures using thermo-time domain reflectometry probe test", Acta Geotechnica, 12(4), 739-752. https://doi.org/10.1007/s11440-016-0506-0.
  45. Zou J.F., Wei. A. and Liang L. (2020), "Analytical solution for steady seepage and groundwater inflow into an underwater tunnel", Geomech. Eng., 20(3), 367-273. https://doi.org/10.12989/gae.2020.20.3.267.