Note on the Interaction Factor for Two Laterally Loaded Piles
Publication: Journal of Geotechnical and Geoenvironmental Engineering
Volume 134, Issue 11
Abstract
This technical note revisits the interaction factors for two piles under lateral loading by means of a rigorous analytical method. The basic idea of the approach presented is to decompose the problem into an extended elastic soil and two fictitious piles having Young’s modulus equal to the difference between the modulus of the real pile and the surrounding soil. By considering the displacement compatibility condition, the pile–soil interaction problem is found to be governed by a Fredholm equation of the second kind. The displacement and bending moment distribution along the fictitious piles, and consequently, the desired interaction factor at the pile head are obtained. Comparison with existing solutions validates the accuracy of the present formulation and confirms that the conventional interaction factor approach would exaggerate the interaction effect for long flexible piles. Some numerical examples are presented to illustrate the influences of the pile spacing, pile–soil stiffness ratio, pile slenderness ratio, and departure angle of the loading direction on the calculated results. A set of interaction factor charts is also provided.
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Acknowledgments
The writers gratefully acknowledge the financial support from the National Natural Science Foundation of China, under Grant No. 50478022. The first writer also wants to thank Prof. Abousleiman, PoroMechanics Institute, University of Oklahoma, for reading the manuscript and valuable comments. Please note that the work reported in this technical note was finished in Shanghai Jiaotong University under the financial support from the National Natural Science Foundation of China (No. 50478022), when the first writer held a position of Associate Professor in Dept. of Civil Engineering, SJTU. So, the first writer S. L. Chen is still affiliated to “Shanghai Jiaotong Univ”.
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Information & Authors
Information
Published In
Journal of Geotechnical and Geoenvironmental Engineering
Volume 134 • Issue 11 • November 2008
Pages: 1685 - 1690
Copyright
© 2008 ASCE.
History
Received: Feb 13, 2007
Accepted: Dec 21, 2007
Published online: Nov 1, 2008
Published in print: Nov 2008
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