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.
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Information & Authors
Information
Published In
International Journal of Geomechanics
Volume 7 • Issue 3 • May 2007
Pages: 194 - 205
Copyright
© 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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