Limit Analysis of Rigid Foundations on Floating Columns
Publication: International Journal of Geomechanics
Volume 9, Issue 3
Abstract
This study applies the limit analysis to estimate the bearing capacity of a rigid foundation on a soil reinforced by a group of floating columns. The lower bounds of the bearing capacity are derived in terms of a dimensionless factor that depends on the characteristics of the soil and the inclusion, the area replacement ratio, the columns length, and a uniform surcharge surrounding the foundation. The established results are valid for a variety of reinforcing configurations in terms of arbitrary foundation shape and any randomly distributed column arrangements under the foundation. The computation of the bearing capacity is extended to the kinematic approach of the limit analysis for reinforcement of purely cohesive soils. For symmetrical column arrangement the upper bound of bearing capacity factor is calculated by the Prandtl’s mechanism failure. Previous results established for the reinforcement case by end-bearing columns remain valid when considering floating columns. Nevertheless, a limitation on the length of columns is required for some reinforcement cases. The reliability of the results of limit analysis is illustrated by comparison with two other published methods.
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Acknowledgments
The writers appreciate the comments by the anonymous reviewers that enhanced the quality of this presentation. Financial support by a U.S. Fulbright program for the first writer is gratefully acknowledged.
References
Barksdale, R. D. (1987). “Applications of the state of the art of stone columns—Liquefaction, local bearing and example calculations.” Technical Rep. No. REMR GT-7, U.S. Corps of Engineers, Washington, D.C.
Barksdale, R. D., and Bachus, R. C. (1983). “Design and construction of stone columns.” Vol., 1 Rep. No., 1, FHWA/RD 83/026, Federal Highway Administration, Washington, D.C.
Bouassida, M. (1996). “Etude expérimentale du renforcement de la vase de Tunis par colonnes de sable—Application pour la validation de la résistance en compression théorique d’une cellule composite confinée.” Revue Française de Géotechnique, 75, 3–12.
Bouassida, M., de Buhan, P., and Dormieux, L. (1995). “Bearing capacity of a foundation resting on a soil reinforced by a group of columns.” Geotechnique, 45(1), 25–34.
Bouassida, M., and Hadhri, T. (1996). “Closure to Extreme load of soils reinforced by columns: The case of an isolated column.” Soils Found., 36(1), 118–119.
Bouassida, M., and Hadhri, T. (1998). “Capacité portante d’une fondation posée sur un sol renforcé par un groupe de colonnes.” Revue Marocaine de Génie Civil, 78, 2–16.
Bouassida, M., and Porbaha, A. (2004). “Ultimate bearing capacity of soft clays reinforced by a group of columns—Application to a deep mixing technique.” Soils Found., 44(3), 91–101.
Brauns, J. (1978). “Die anfangstraglast von schottersäulen im bindigen untergrund.” Die Bautechnik, 55(8), 263–271.
Broms, B. G. (1982), “Lime columns in theory and practice.” Proc. Int. Conf. of Soil Mechanics, Mexico, 149–165.
Chen, W. F. (1975). Limit analysis and soil plasticity, Elsevier, Amsterdam, The Netherlands.
Davis, R. O., and Selvadurai, A. P. S. (2002). Plasticity and geomechanics, Cambridge University Press, London.
Drucker, D. C., and Prager, W. (1952). “Soil mechanics and plasticity analysis or limit design.” Q. Appl. Math., 10, 157–165.
Hughes, J. M., and Withers, N. J. (1974). “Reinforcing of soft cohesive soils with stone columns.” Ground Eng.
Jellali, B., Bouassida, M., and de Buhan, P. (2005). “Homogenisation method for bearing capacity estimation.” Int. J. Numer. Analyt. Meth. Geomech., 29(10), 989–1004.
Jellali, B., Bouassida, M., and de Buhan, P. (2007). “A homogenization approach to estimate the ultimate bearing capacity of a stone column reinforced foundation.” Int. J. Geotechnical Engineering, 1, 61–69.
Kasama, K., Zen, K., and Whittle, A. J. (2006). “Effects of spatial variability of cement-treated soil on undrained bearing capacity.” Numerical modeling of construction processes in geotechnical engineering for urban environment, T. Triantafyllidis, ed., Ruhr University Press, Bochum, Germany, 305–313.
Porbaha, A., and Bouassida, M. (2004). “Bearing capacity of foundations resting on soft ground improved by soil cement columns.” Proc., Int. Conf. on Geotechnical Engineering, A. Basma and M. Omar, eds., University of Sharjah, United Arab Emirates, 173–180.
Salençon, J. (1990). “An introduction to the yield design theory and its applications to soil mechanics.” Eur. J. Mech. A/Solids, 9(5), 477–500.
Information & Authors
Information
Published In
International Journal of Geomechanics
Volume 9 • Issue 3 • May 2009
Pages: 89 - 101
Copyright
© 2009 ASCE.
History
Received: May 18, 2007
Accepted: Nov 11, 2008
Published in print: May 2009
Published online: May 15, 2009
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