Role of Linear Elasticity in Pile Group Analysis and Load Test Interpretation
Publication: Journal of Geotechnical and Geoenvironmental Engineering
Volume 136, Issue 12
Abstract
This paper compares linear-elastic and nonlinear pile group analysis methods through settlement analyses of hypothetical scenarios and real case studies, and elaborates on the implications for interpretation of pile load test data. Comparisons between linear-elastic and nonlinear methods justify the proposition that pile-to-pile interaction is dominated by linear elasticity, characterized by the small-strain soil stiffness. As the size of a pile group increases, nonlinearity in individual pile behavior becomes overwhelmed by the interaction effects. In such cases, similar estimates will be achieved by both linear and nonlinear methods if the soil modulus is derived from the initial tangent, rather than some secant stiffness, assessed from the load test data. The study clarifies the capabilities and limitations of linear elasticity in pile group analysis and provides guidance on pile test interpretation for analysis of pile group response.
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Acknowledgments
The writers would like to express their gratitude toward IOS Press and the writers of Mandolini et al. (2005) for their permission to use the material in the mentioned publication. 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 studies at the University of Cambridge.EPSRC
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Information & Authors
Information
Published In
Journal of Geotechnical and Geoenvironmental Engineering
Volume 136 • Issue 12 • December 2010
Pages: 1686 - 1694
Copyright
© 2010 ASCE.
History
Received: Apr 24, 2009
Accepted: May 13, 2010
Published online: May 22, 2010
Published in print: Dec 2010
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