Setup Following Installation of Dynamic Anchors in Normally Consolidated Clay
Publication: Journal of Geotechnical and Geoenvironmental Engineering
Volume 135, Issue 4
Abstract
This paper describes a series of centrifuge model tests designed to assess the increase in capacity of dynamic anchors due to setup in normally consolidated clay. The tests involved measurement of the vertical capacity of 1:200 reduced scale model anchors following various periods of postinstallation consolidation. The short-term capacity was shown to be dependent on the anchor impact velocity. Cavity expansion solutions for consolidation around a solid driven pile were found to provide agreement with the experimental results. A simplified capacity calculation technique predicted higher friction ratio values than is typically observed for driven piles; however, these calculations were complicated by the unusual dynamic anchor load–displacement response and uncertainty regarding the true sample shear strength. Dynamic anchor consolidation proceeds at a slower rate than for suction caissons and open-ended piles of similar equivalent diameter. However, the results indicate that depending on the site conditions, dynamically installed anchors remain a viable alternative to conventional deep-water mooring techniques.
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Acknowledgments
The work described here forms part of the activities of the Centre for Offshore Foundation Systems, established under the Australian Research Council’s Research Centres Program and currently supported as a Centre of Excellence by the State of Western Australia. This project has been funded by the Australian Research Council and Woodside Energy under Grant No. LP0562561. The technical support provided by Mr. Bart Thompson and Mr. John Breen is gratefully acknowledged.
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Information & Authors
Information
Published In
Journal of Geotechnical and Geoenvironmental Engineering
Volume 135 • Issue 4 • April 2009
Pages: 487 - 496
Copyright
© 2009 ASCE.
History
Received: Aug 7, 2007
Accepted: Jun 16, 2008
Published online: Apr 1, 2009
Published in print: Apr 2009
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