Reinforced Soil Using Cohesive Fill and Electrokinetic Geosynthetics
Publication: International Journal of Geomechanics
Volume 5, Issue 2
Abstract
An electrokinetic geosynthetic (EKG), is a polymeric geosynthetic material, enhanced to conduct electricity, which can be used to transport water in fine-grained soils by electrokinetic means. This paper describes the design, construction details, and analysis of a reinforced soil wall using EKG and wet cohesive fill. In order to establish an initial design layout, a long-term stability analysis of the wall was carried out using the soil’s critical state shear strength parameters. The long-term design was then checked for short-term stability based upon a minimum required undrained shear strength for the clay utilizing four different short-term analytical methods: critical height, Coulomb, discrete theory, and composite theory. The electroosmosis design was then undertaken, based upon the water content—undrained shear strength curve for the fill material ascertained from laboratory testing. Using this curve the difference between the as-placed water content and the water content corresponding to an undrained shear strength of was calculated, giving the volume of water that needed to be removed from each lift of clay fill. Using this volume of water the electroosmosis calculations were undertaken. A simplistic analysis was undertaken using a linear voltage gradient and fixed soil parameters, followed by a more complex analysis using finite difference techniques to establish the voltage gradient. The variation in the value of electro-osmotic permeability were estimated using both an empirical model and a graphical interpretation of the actual variation of measured in the laboratory. The results of these analyses yielded estimated treatment times and undrained shear strength of the clay.
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Acknowledgments
The writers would like to thank the Engineering and Physical Sciences Research Council for supporting the work. Skanska Cementation, Tensar International Ltd. CAPITOL, Naue Fasertechnik GmbH, Okasan Livic Co., Ltd. provided funding, materials, construction equipment, and invaluable advice.
Reference
Bjerrum, L., Moum, J., and Eide, G. (1967). “Application of electroosmosis to a foundation problem in a Norwegian quick clay.” Geotechnique, 17, 214–235.
British Standards Institution (BSI). (1990). “British standard methods of test for soils for civil engineering purposes.” BS 1377, London.
British Standards Institution (BSI). (1995). “Code of practice for strengthened/reinforced soil and other fills.” BS 8006, London.
Casagrande, L. (1952). “Electro-osmotic stabilisation of soils.” J. Boston Soc. Civ. Eng., 39, 51–83.
Coulomb, C. A. (1776). “Essai sur une application des régeles des maximus et minimus a quelque problémes de statique re’latif à l’architecture.” Memoirs Divers Savants, Vol. 7, Académie Sciences, Paris.
Hamir, R. B. (1997). “Some aspects and applications of electrically conductive geosynthetic materials.” Doctor of Philosophy thesis, Univ. of Newcastle upon Tyne, Newcastle upon Tyne, U.K., 225–225.
Hamir, R. B., Jones, C. J. F. P., and Clarke, B. G. (2001). “Electrically conductive geosynthetics for consolidation and reinforcement.” Geotext. Geomembr., 19(8), 455–483.
Jones, C. J. F. P. (1990). “Construction influences on the performance of reinforced soil structures, state-of-the-art review.” Proc., Int. Conf. on Reinforced Soil, Glasgow, Scotland, 97–116.
Jones, C. J. F. P. (1996). Earth reinforcement and soil structures, Thomas Telford, London, 379–379.
Jones, C. J. F. P., Fakher, A., Hamir, R., and Nettleton, I. M. (1996). “Geosynthetic materials with improved reinforcement capabilities.” Proc., Int. Symp. on Earth Reinforcement, Fukuoka, Kyushu, Japan, 865–883.
Lo, K. Y., Ho, K. S., and Inculet, I. I. (1991a). “Field test of electroosmotic strengthening of soft sensitive clay.” Can. Geotech. J., 28, 74–83.
Lo, K. Y., Inculet, I. I., and Ho, K. S. (1991b). “Electroosmotic strengthening of soft sensitive clay.” Can. Geotech. J., 28, 62–73.
Mitchell, J. K. (1993). Fundamentals of soil behaviour, 2nd Ed., Wiley, New York, 437–437.
Mitchell, J. K., and Wan, T. Y. (1977). “Electro-osmotic consolidation—Its effects on soft soils.” Proc., 9th Int. Conf. on Soil Mechanics and Foundation Engineering, Tokyo, Vol. 1, Balkema, Rotterdam, The Netherlands, 219–224.
Netlon Ltd. (1998). Winwall Version 6.14., Reinforced Soil Design Package, Tensar International, Blackburn, U.K.
Nettleton, I. M., Jones, C. J. F. P., Clarke, B. G., and Hamir, R. (1998). “Electrokinetic geosynthetics and their applications.” Proc., 6th Int. Conf. on Geosynthetics, Atlanta, Vol. 2, 871–876.
Pugh, R. C. (2002). “The application of electrokinetic geosynthetic materials to uses in the construction industry.” PhD thesis, Univ. of Newcastle upon Tyne, Newcastle upon Tyne, U.K.
Stroud, K. A. (1990). Further engineering mathematics—Programmes and problems, 2nd Ed., Macmillan Education, London, 1063–1063.
Terzaghi, K., and Peck. (1967). Soil mechanics in engineering practice, 2nd Ed., Wiley, New York, 566–566.
Williams, B. P, Smyrell, A. G., and Lewis, P. J. (1993). “Flownet diagrams—The use of finite differences and a spreadsheet to determine potential heads.” Ground Eng., 32–38.
Young, H. D., and Freedman, R. A. (1996). University physics, 9th Ed., Addison-Wesley, Reading, Mass., 1259–1259.
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© 2005 ASCE.
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Received: Feb 18, 2004
Accepted: Oct 25, 2004
Published online: Jun 1, 2005
Published in print: Jun 2005
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