Theoretical Study on Pile Length Optimization of Pile Groups and Piled Rafts
Publication: Journal of Geotechnical and Geoenvironmental Engineering
Volume 136, Issue 2
Abstract
Pile groups are frequently designed with equal or similar pile lengths. However, the significant interaction effects among equal-length piles imply that this may not be the optimized configuration. This paper presents the optimization analyses of piled rafts and freestanding pile groups, where pile lengths are varied across the group to optimize the overall foundation performance. The results of the analyses are applicable in cases where the piles derive a majority of the capacity from the frictional resistance. It is demonstrated that, with the same amount of total pile material, an optimized pile length configuration can both increase the overall stiffness of the foundation and reduce the differential settlements that may cause distortion and cracking of the superstructure. The benefits of the optimization can be translated to economic and environmental savings as less material is required to attain the required level of foundation performances. The reliability of the optimization benefits in relation to construction-induced variability is also discussed.
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Acknowledgments
The work presented in this paper is part of the Smart Foundations project (Grant No. UNSPECIFIEDEP/D040000/1) funded by the Engineering and Physical Sciences Research Council (EPSRC). Their financial support is gratefully acknowledged. The first writer would also like to express his gratitude to the Cambridge Overseas Trust (COT) for additional funding supporting his study at the Cambridge University.UNSPECIFIED
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Information & Authors
Information
Published In
Journal of Geotechnical and Geoenvironmental Engineering
Volume 136 • Issue 2 • February 2010
Pages: 319 - 330
Copyright
© 2010 ASCE.
History
Received: Jun 4, 2008
Accepted: Jul 26, 2009
Published online: Aug 1, 2009
Published in print: Feb 2010
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