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Study of physical simulation of electrochemical modification of clayey rock

  • Chai, Zhaoyun (Mining Technology Institute, Taiyuan University of Technology) ;
  • Zhang, Yatiao (Mining Technology Institute, Taiyuan University of Technology) ;
  • Scheuermann, Alexander (School of Civil Engineering, the University of Queensland)
  • Received : 2015.01.28
  • Accepted : 2016.04.22
  • Published : 2016.08.25

Abstract

Clayey rock has large clay mineral content. When in contact with water, this expands considerably and may present a significant hazard to the stability of the rock in geotechnical engineering applications. This is particularly important in the present work, which focused on mitigating some unwelcomed properties of clayey rock. Changes in its physical properties were simulated by subjecting the rock to a low voltage direct current (DC) using copper, steel and aluminum electrodes. The modified mechanism of the coupled electrical and chemical fields acting on the clayey rock was analyzed. It was concluded that the essence of clayey rock electrochemical modification is the electrokinetic effect of the DC field, together with the coupled hydraulic and electrical potential gradients in fine-grained clayey rock, including ion migration, electrophoresis and electro-osmosis. The aluminum cathodes were corroded and generated gibbsite at the anode; the steel and copper cathodes showed no obvious change. The electrical resistivity and uniaxial compressive strength (UCS) of the modified specimens from the anode, intermediate and cathode zones tended to decrease. Samples taken from these zones showed a positive correlation between electric resistivity and UCS.

Keywords

Acknowledgement

Supported by : National Natural Science Foundation of China, Shanxi Province Science Foundation for Youths

References

  1. Acar, Y.B. and Alshawabkeh, A.K. (1993), "Principles of electrokinetic remediation", Environ. Sci. Technol., 37(13), 2638-2647.
  2. Aggour, M.A. and Muhammadain, A.M. (1992), "Investigation of water-flooding under the effect of electrical potential gradient", J. Petrol. Sci. Eng., 7(3/4), 319-327. https://doi.org/10.1016/0920-4105(92)90027-X
  3. Aggour, M.A., Tchelepi, H.A. and Yousef, H.Y. (1994), "Effect of electroosmosis on relative permeability of sandstones", J. Petrol. Sci. Eng., 11(2), 91-102. https://doi.org/10.1016/0920-4105(94)90031-0
  4. Alejano, L.R., Rodriguez-Dono, A., Alonso, E. and Fdez-Manin, G. (2009), "Ground reaction curves for tunnels excavated in different quality rock masses showing several types of post-failure behaviour", Tunn. Undergr. Space Technol., 24(6), 689-705. https://doi.org/10.1016/j.tust.2009.07.004
  5. Arya, A.L. and Ian, J. (2013), "Collapsibility in calcareous clayey loess: A factor of stresss-hydraulic history", Int. J. GEOMATE, 5(1), 620-627.
  6. Bernabeu, A., Exposito, E., Montiel, V., Ordonez, S. and Aldaz, A. (2001), "A new electrochemical method for consolidation of porous rocks", Electrochem. Commun., 3(3), 122-127. https://doi.org/10.1016/S1388-2481(01)00117-5
  7. Burnotte, F., Lefebvre, G. and Grondin, G. (2004), "A case record of electroosmotic consolidation of soft clay with improved soil-electrode contact", Can. Geotech. J., 41(6), 1038-1053. https://doi.org/10.1139/t04-045
  8. Chai, Z.Y., Kang, T.H. and Feng, G.R. (2014a), "Effect of aqueous solution chemistry on the swelling of clayey rock", Appl. Clay Sci., 48(93/94), 12-15.
  9. Chai, Z.Y., Kang, T.H. and Chen, W.Y. (2014b), "Effects of organic silicone additive material on physical and mechanical properties of mudstone", Geomech. Eng., Int. J., 6(2), 139-151. https://doi.org/10.12989/gae.2014.6.2.139
  10. Chilingar, G. (1970), "Effect of direct electrical current on permeability of sandstone cores", J. Pet. Technol., 22(7), 8-17.
  11. Corkum, A.G. and Martin, C.D. (2007), "The mechanical behaviour of weak mudstone (Opalinus Clay) at low stresses", Int. J. Rock Mech. Min. Sci., 44(2), 196-209. https://doi.org/10.1016/j.ijrmms.2006.06.004
  12. Dong, X., Su, N., Huang, X. and Bai, X. (2014) "Effect of sewage on electrical resistivity and strength of cemented soil", Rock Soil Mech., 35(7), 1855-1862.
  13. Erguler, Z.A. and Ulusay, R. (2009), "Water-induced variations in mechanical properties of clay-bearing rocks", Int. J. Rock Mech. Min. Sci., 46(2), 355-370. https://doi.org/10.1016/j.ijrmms.2008.07.002
  14. Hideo, K. (2004), "Simplified evaluation for swelling characteristics of Bentonites", Eng. Geol., 71(3/4), 265-279. https://doi.org/10.1016/S0013-7952(03)00140-6
  15. Jeng, F.S., Wang, M.C., Huang, T.H. and Liu, M.L. (2002), "Deformational characteristics of weak sandstone and impact to tunnel deformation", Tunn. Undergr. Space Technol., 17(3), 263-274. https://doi.org/10.1016/S0886-7798(02)00011-1
  16. Lo, K.Y., Inculet, I.I. and Ho, K.S. (1991), "Electroosmotic strengthening of soft sensitive clays", Can. Geotech. J. 28(1),62-73. https://doi.org/10.1139/t91-007
  17. Mikhajlovich, P.S. (2001), "Process of electrochemical strengthening of rock", Russia Patent; No. 2299294.
  18. Mikhajlovich, P.S. (2006), "Method for electrochemical rock consolidation", Russia Patent; No. 2175040.
  19. Mitchell, J.K. (1993), Fundamentals of Soil Bahaviour, (2nd Ed.), John Wiley & Sons Inc., New York, NY, USA.
  20. Nasim, M., Erwin, O. and Gary, C. (2012), "A review of electrokinetic treatment technique for improving the engineering characteristics of low permeable problematic soils", Int. J. GEOMATE, 2(2), 266-272.
  21. Ou, C., Chien, S. and Chang, H. (2009), "soil improvement using electroosmosis with the injection of chemical soluteions: Field fests", Can. Geotech. J., 46(6), 727-733. https://doi.org/10.1139/T09-012
  22. Pham, Q.T., Vales, F., Malinsky, L., Minh, D.N. and Gharbi, H. (2007), "Effects of desaturation resaturation on mudstone", Phys. Chem. Earth, Parts A/B/C, 32(8-14), 646-655. https://doi.org/10.1016/j.pce.2006.03.012
  23. Pinzari, U. (1962), "Indagine sul trattamento elettrosmotico di un materiale argilloso", Geotecnica, 9(3), 101-114.
  24. Shao, J.F., Ata, N. and Ozanam, O. (2005), "Study of desaturation and resaturation in brittle rock with anisotropic damage", Eng. Geol., 81(3), 341-352. https://doi.org/10.1016/j.enggeo.2005.06.015
  25. Wang, D., Kang, T., Chai, Z., Han, W. and Liu, Z. (2009), "Experimental studies of subsidence and expandability of montmorillonitic soft rock particles under electrochemical treatment", Chin. J. Rock Mech. Eng., 28(9), 1876-1883.
  26. Wang, D., Kang, T.H., Han, W.M., Liu, Z.P. and Chai, Z.Y. (2010), "Electrochemical modification of the porosity and zeta potential of montmorillonitic soft rock", Geomech. Eng., Int. J., 2(3), 191-202 https://doi.org/10.12989/gae.2010.2.3.191
  27. Wang, D., Kang, T.H., Han, W.M. and Liu, Z.P. (2011), "Electrochemical modification of tensile strength and pore structure in mudstone", Int. J. Rock Mech. Min. Sci., 48(4), 687-692. https://doi.org/10.1016/j.ijrmms.2011.02.012

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