Bearing Capacity of a Skirted Square Footing under Eccentric Loading in Granular Soil
Publication: International Journal of Geomechanics
Volume 24, Issue 5
Abstract
The ultimate bearing capacity of a shallow footing decreases when it is subjected to a moment in addition to a centric vertical load. A centric vertical load with a moment on a footing is equivalent to an eccentric load on the footing. The result of this is a net reduction of the ultimate and allowable bearing capacity of the footing. In a situation like this, the bearing capacity of the footing can be improved by providing a skirt around the footing. The present study provides the results of a laboratory test program of a skirted square (B × B) model footing in dense and medium-dense sand as it relates to the ultimate bearing capacity. For the tests, the length of the skirt (L) was varied as L/B = 0, 0.25, 0.5, 0.75, and 1.0. Based on the model test results, relationships have been developed to estimate the ultimate bearing capacity of a skirted footing with eccentric vertical loading from the ultimate bearing capacity of a footing without a skirt subjected to vertical centric loading.
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Data Availability Statement
Some or all data, models, or codes that support the findings of this study are available from the corresponding author upon reasonable request. All data used to generate figures and tables in this paper are available.
Acknowledgments
The authors gratefully acknowledge the valuable and insightful suggestions made by the late Professor Braja M. Das in improving the technical manuscript.
Notation
The following symbols are used in this paper:
- B
- width of a footing;
- D
- embedment depth;
- D50
- median particle size;
- Dr
- relative density;
- e
- eccentricity;
- L
- length of a skirt;
- q
- pressure;
- qu
- ultimate bearing capacity;
- qu,sk
- ultimate bearing capacity of a skirted footing;
- qu,sp
- ultimate bearing capacity of a spread footing;
- qu(e)
- ultimate bearing capacity under an eccentric load;
- qu(e=0)
- ultimate bearing capacity under a centric load;
- su
- average settlement at ultimate load; and
- ϕ
- angle of internal friction.
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Published In
International Journal of Geomechanics
Volume 24 • Issue 5 • May 2024
Copyright
© 2024 American Society of Civil Engineers.
History
Received: May 15, 2023
Accepted: Nov 5, 2023
Published online: Feb 22, 2024
Published in print: May 1, 2024
Discussion open until: Jul 22, 2024
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