Effects of Isolated Spread Footings on the Dynamics of Soil-Structure Interaction
Publication: Journal of Geotechnical and Geoenvironmental Engineering
Volume 138, Issue 8
Abstract
The objective of this work is to examine the dynamics of soil-structure systems supported on isolated spread footings, in contradistinction with the rigid basemat often used in soil-structure interaction (SSI) studies. By considering a column-supported single-story structure on isolated footings, an explicit formula for the fundamental natural period of the system was obtained. This allows examination of the relative importance of the various system parameters that cause the natural period of the SSI system to increase compared with that of the corresponding fixed-base system. The key parameter is the relative stiffness of an individual column to the rocking stiffness of the corresponding footing. If this parameter is small (), there is little interaction (change in period ). If it is large (), the base of the column behaves essentially as a hinge, and the natural period tends to double with respect to that of the structure on a rigid base because of the effect of rocking of the individual footings. The lateral and vertical stiffness of the individual footings play a lesser role. Numerical results for a particular model illustrate this effect.
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Acknowledgments
The writers are grateful to the reviewers for their thoughtful comments and suggestions, which greatly helped them to improve the original article.
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Information & Authors
Information
Published In
Journal of Geotechnical and Geoenvironmental Engineering
Volume 138 • Issue 8 • August 2012
Pages: 1033 - 1036
Copyright
© 2012. American Society of Civil Engineers.
History
Received: Dec 3, 2010
Accepted: Nov 29, 2011
Published online: Dec 1, 2011
Published in print: Aug 1, 2012
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