Displacement of Spread Footings on Aggregate Pier Reinforced Clay
Publication: Journal of Geotechnical and Geoenvironmental Engineering
Volume 140, Issue 1
Abstract
Aggregate piers, also known as stone columns, are commonly used to improve ground for the support of structure foundations. Despite the number of existing analytical and semiempirical methods available to predict the displacement of shallow foundations resting on aggregate pier reinforced clay, the accuracy of these models remains uncertain. After a brief review of existing load-displacement estimation methods, the accuracy of those models valid for isolated spread footings was investigated using a database of high-quality footing load test data. The methods were compared using the bias (i.e., the ratio of measured bearing capacity to that calculated) and were shown to exhibit a high degree of variability in the prediction of load and displacement. Then, the database was used to develop a multiple linear regression model for the prediction of footing displacements for aggregate pier reinforced clay under a wide range of pier configurations and soil conditions. The proposed statistical model is shown to produce unbiased displacement estimates with low prediction variability that is appropriate for planning and designing ground-improvement projects.
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Acknowledgments
The authors gratefully acknowledge Hayward Baker Inc. for construction of the aggregate piers and funding the field and laboratory test program. Additional support was provided by the Valle and ARCS Fellowship Programs through the University of Washington.
Disclaimer
None of the aggregate piers tested as part of this study were designed, installed, or tested by, under the supervision, with authorization from, or in compliance with the specifications for the patented and proprietary technology of Geopier. The installation and testing was not conducted by any independent party.
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Information & Authors
Information
Published In
Journal of Geotechnical and Geoenvironmental Engineering
Volume 140 • Issue 1 • January 2014
Pages: 36 - 45
Copyright
© 2014 American Society of Civil Engineers.
History
Received: May 22, 2012
Accepted: Jun 9, 2013
Published online: Jun 11, 2013
Published in print: Jan 1, 2014
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