Undrained Limit States of Shallow Foundations Acting in Consort
Publication: International Journal of Geomechanics
Volume 7, Issue 3
Abstract
There is no established procedure for the calculation of bearing capacity of a shallow foundation system comprising cojoined footings. Ad hoc approaches are relied on and may simply involve summing the ultimate limit states of the individual footings as if they acted independently; neglecting additional capacity of the system available from the kinematic constraint provided by the structural connection between the footings. In this study, the undrained capacity under general loading of rigidly connected two-footing systems at various separations has been investigated with finite-element analyses. Results are presented in terms of ultimate limit states under pure vertical , horizontal , and moment loading, and failure envelopes defining limiting load states under combined , , , and loads. Kinematic failure mechanisms observed in the finite-element analyses are presented and in cases used to provide the basis for upper bound solutions.
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Acknowledgments
The work described here forms part of the activities of the Special Research Centre for Offshore Foundation Systems, established and supported under the Australian Research Council’s Research Centres Program. This support is gratefully acknowledged. The writers would also like to express their thanks to Professor Guy Houlsby from the University of Oxford, U.K., for his advice regarding the upper bound solutions while a visitor at Centre for Offshore Foundation Systems.
References
Bransby, M. F., and Randolph, M. F. (1998). “Combined loading of skirted foundations.” Geotechnique, 48(5), 637–655.
Brinch Hansen, J. (1970). “A revised and extended formula for bearing capacity.” Danish Geotechnical Institute bulletin no. 28, Coperhagen, 5–11.
Butterfield, R., and Gottardi, G. (1994). “A complete three-dimensional failure envelope for shallow foundations on sand.” Geotechnique, 44(1), 181–184.
Butterfield, R., Houlsby, G. T., and Gottardi, G. (1997). “Standardised sign conventions and notation for generally loaded foundations.” Geotechnique, 47(5), 1051–1054.
Dean, E. T. R., James, R. G., Schofield, A. N., Tan, F. S. C., and Tsukamoto, Y. (1992). “The bearing capacity of conical footings on sand in relation to the behaviour of spudcan footings of jackups.” Proc., Wroth Memorial Symp. Predictive Soil Mechanics, Oxford, U.K., 230–253.
Fisher, R., and Cathie, D. (2003). “Optimisation of gravity based design for subsea applications.” Proc., Int. Conf. on Foundations (ICOF), Dundee, Scotland.
Green, A. P. (1954). “The plastic yielding of metal junctions due to combined shear and pressure.” J. Mech. Phys. Solids, 2(3), 197–211.
Gourvenec, S., and Randolph, M. R. (2003). “Effect of strength non-homogeneity on the shape and failure envelopes for combined loading of strip and circular foundations on clay.” Geotechnique, 53(6), 575–586.
Hibbit, Karlsson, and Sorensen, Inc. (HKS). (2002). ABAQUS users’ manual, version 6.1, Pawtucket, R.I.
Houlsby, G. T., and Puzrin, A. M. (1999). “The bearing capacity of a strip footing on clay under combined loading.” Proc. R. Soc. London, Ser. A, 455, 893–916.
Meyerhof, G. G. (1953). “The bearing capacity of foundations under eccentric and inclined loads.” Proc., 3rd Int. Conf. Soil Mechanics and Foundation Engineering, Vol. 1, 440–445.
Murff, J. D. (1994). “Limit analysis of multifooting foundation systems.” Proc., 8th Int. Conf. Computer Methods and Advances in Geomechanics, Morgantown, Vol. 1, 223–244.
Murff, J. D, and Hamilton, J. M. (1993). “ -ultimate for undrained analysis of laterally loaded piles.” J. Geotech. Engrg., 119(1), 91–107.
Osborne, J. J., Trickey, J. C., Houlsby, G. T., and James, R. G. (1991). “Findings from a joint industry study on foundation fixity of jackup units.” Proc., Annual Offshore Technology Conf., OTC 6615, Houston.
Prandtl, L. (1921). “Eindringungsfestigkeit und festigkeit von schneiden.” Angew. Math. U. Mech, 1(15).
Randolph, M. F., and Puzrin, A. M. (2003). “Upper bound limit analysis of circular foundations on clay under general loading.” Geotechnique, 53(9), 785–796.
Salençon, J., and Pecker, A. (1995) “Ultimate bearing capacity of shallow foundations under inclined and eccentric loads—I: Purely cohesive soil.” Eur. J. Mech. A/Solids, 4, 349–375.
Taiebat, H. A., and Carter, J. P. (2000). “Numerical studies of the bearing capacity of shallow foundations on cohesive soil subjected to combined loading.” Geotechnique, 50(4), 409–418.
Taiebat, H. A., and Carter, J. P. (2002). “Bearing capacity of strip and circular foundations on undrained clay subjected to eccentric loads.” Geotechnique, 52(1), 61–64.
Terzaghi, K. (1943). Theoretical soil mechanics, Wiley, New York.
Ukritchon, B., Whittle, A. J., and Sloan, S. W. (1998). “Undrained limit analysis for combined loading of strip footings on clay.” J. Geotech. Geoenviron. Eng., 124(3), 265–276.
Vesic, A. S. (1975). “Bearing capacity of shallow foundations.” Foundation engineering handbook, H. F. Winterkorn and H. Y. Fang, eds., Van Nostrand, New York, 121–147.
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© 2007 ASCE.
History
Received: Dec 8, 2005
Accepted: May 2, 2006
Published online: May 1, 2007
Published in print: May 2007
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