Coupled-Consolidation Modeling of a Pile in Consolidating Ground
Publication: Journal of Geotechnical and Geoenvironmental Engineering
Volume 138, Issue 7
Abstract
When a pile is embedded in a consolidating ground (e.g., newly reclaimed land), soil may settle more than the pile, thus generating negative skin friction along the pile shaft. This negative friction induces additional axial load to the pile (dragload) and pulls the pile further downward (downdrag). In this paper, the problem is investigated numerically with the finite-element package ABAQUS. It was found that the package defaults an interface model that models the mobilized interface strength in a way that the effect of water pressure was overlooked. Therefore, a modified numerical algorithm is proposed in this study. It amends the model by correctly bringing pore water pressure into the calculation steps. which properly simulates the effective stress-dependent nature of the shear strength at the soil-pile interface. The algorithm is then verified by a self-contained simple to understand simulation. A case history of two piles (one of them coated with bitumen) embedded in a consolidating soft ground is then back analyzed with the proposed algorithm. Fully coupled consolidation and geometric nonlinearity are also considered in the analyses. The transient response of the problem is investigated, including the development of dragload, downdrag, and neutral plane with time. The simulation generally fits well with the field measurements. Parametric studies of the effects of pile head loading reveal that the position of the neutral plane depends not only on the magnitude of the applied pile head loading, but is also affected when the load is applied with respect to the consolidation process.
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Acknowledgments
The writers wish to thank the anonymous reviewers, whose valuable comments and suggestions improved the quality of this paper.
References
ABAQUS [Computer software]. Providence, RI, ABAQUS Inc.
Acar, Y. B., Avent, R., and Taha, M. R. (1994). “Downdrag on friction piles: a case history.” Proc., Settlement 94: Vertical and Horizontal Deformation of Foundations and Embankment, ASCE GSP, 40, 986–999.
Alonso, E. E., Josa, A., and Ledesma, A. (1984). “Negative skin friction on piles: a simplified analysis and prediction procedure.” Geotechnique, 34(3), 341–357.GTNQA8
Bozozuk, M. (1970). “Field observations of negative skin friction loads on long piles in marine clay.” Proc., Conf. on Design and Installation of Pile Foundations and Cellular Structure., Lehigh University, Bethlehem, PA, 279–279.
Bozozuk, M. (1972). “Downdrag measurements on a 160-ft floating pipe test pile in marine clay.” Can. Geotech. J.CGJOAH, 9(2), 127–136.
Endo, M., Minou, A., Kawasaki, T., and Shibata, T.(1969). “Negative skin friction acting on steel piles in clay.” Proc., 8th Int. Conf. on Soil Mechanics and Foundation Engineering, Mexico City, 2, 85–92.
Fellenius, B. H. (1972). “Down-drag on piles in clay due to negative skin friction.” Can. Geotech. J.CGJOAH, 9(4), 323–337.
Fellenius, B. H. (1999). Basics of foundation design. Second expanded edition. Static analysis of pile load-transfer, BiTech Publishers Ltd., Richmond, British Columbia, 172–173.
Fellenius, B. H. (2006). “Results from long-term measurement in piles of drag load and downdrag.” Can. Geotech. J.CGJOAH, 43(4), 409–430.
Fukuya, T., Todoroki, T., and Kasuga, M. (1982). “Reduction of negative skin friction with steel tube NF pile.” Proc., 7th Asian Geotech. Conf., Hong Kong, 333–347.
Guo, W. D., and Randolph, M. F. (1997). “Vertically loaded piles in non-homogeneous media.” Int. J. Numer. Anal. Methods Geomech., 21(8), 507–532.IJNGDZ
Horpibulsuk, S., Shibya, S., Fuenkajorn, K., and Katkan, W. (2007). “Assessment of engineering properties of Bangkok clay.” Can. Geotech. J.CGJOAH, 44(2), 173–187.
Indraratna, B., Balasubramaniam, A. S., Phamvan, P., and Wong, Y. K. (1992). “Development of negative skin friction on driven piles in soft Bangkok clay.” Can. Geotech. J.CGJOAH, 29(3), 393–404.
Jeong, S., Kim, S., and Briaud, J. L. (1997). “Analysis of downdrag on pile groups by the finite element method.” Comput. Geotech., 21(2), 143–161.CGEOEU
Jeong, S., Lee, J., and Lee, C. J. (2004). “Slip effect at the soil-pile interface on dragload.” Comput. Geotech., 31(2), 115–126.CGEOEU
Lam, S. Y., Ng, C. W. W., Leung, C. F., and Chan, S. H. (2009). “Centrifuge and numerical modeling of axial load effects on piles in consolidating ground.” Can. Geotech. J.CGJOAH, 46(1), 10–24.
Lee, P. K. K., and Lumb, P. (1982). “Field measurements of negative skin friction on steel tube piles in Hong Kong.” Proc., 7th Asian Geotechnical Conf. Hong Kong, 363–374.
Lee, C. J., and Ng, W. W. (2004). “Development of downdrag on piles and pile groups in consolidating soil.” J. Geotech. Geoenviron. Eng., 130(9), 905–914.JGGEFK
Leung, C. F., Radhakrishnan, R., and Tan, S. A. (1991). “Performance of precast driven piles in marine clay.” J. Geotech. Eng.117(4), 637–657.JGENDZ
Poulos, H. G. (1997). “Piles subjected to negative friction: a procedure for design.” Geotech. Eng., 28(1), 23–44.GTEGB2
Shakir, R. R., and Zhu, J. (2009). “Behavior of compacted clay-concrete interface.” Front. Archit. Civ. Eng. China, 3(1), 85–92.
Tsubakihara, Y., and Kishida, H. (1993). “Frictional behaviour between normally consolidated clay and steel by two direct shear type apparatuses.” Soil Found., 33(2), 1–13.
Walker, L. K., and Darvall, P. (1973). “Downdrag on coated and uncoated piles.” Proc., 8th Int. Conf. in Soil Mech. & Found. Engrg., Moscow, USSR, 2(1), 257–262.
Wong, K. S., and Teh, C. I. (1995). “Negative skin friction on piles in layered soil deposits.” J. Geotech. Eng., 121(6), 457–465.JGENDZ
Information & Authors
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Published In
Journal of Geotechnical and Geoenvironmental Engineering
Volume 138 • Issue 7 • July 2012
Pages: 789 - 798
Copyright
© 2012. American Society of Civil Engineers.
History
Received: Dec 28, 2010
Accepted: Oct 20, 2011
Published online: Jun 15, 2012
Published in print: Jul 1, 2012
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