Keying of Rectangular Plate Anchors in Normally Consolidated Clays
Publication: Journal of Geotechnical and Geoenvironmental Engineering
Volume 137, Issue 12
Abstract
The loss in anchor embedment during keying, as it rotates to become normal to the cable load, reduces the uplift capacity of anchors in normally consolidated clay. The keying behavior of plate anchors has been studied previously by using centrifuge and field model tests. In this paper, a large deformation finite-element approach incorporating frequent mesh regeneration and allowing for evolution of the anchor-chain profile, was developed to simulate the keying process of rectangular and strip plate anchors. A parametric study was undertaken to quantify the loss in anchor embedment during keying in terms of the anchor geometry, soil properties, loading eccentricity, and inclination. The embedment loss decreased dramatically with increasing loading eccentricity and decreasing chain angle at the mudline to the horizontal. The loss in anchor embedment during keying increased as the local soil strength increased relative to the weight of the anchor, up to a limit determined by the eccentricity of loading. In contrast, the effect of the soil strength gradient was minimal. Findings of this study yield a recommendation that the most important factor in anchor keying, loading eccentricity, should not be less than half the anchor width for an effective design.
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Acknowledgments
The work described in this paper was supported by the Australian Research Council through the Discovery Project Scheme (UNSPECIFIEDDP 0344019) and contributes to the research program of the Centre for Offshore Foundation Systems supported by the State Government of Western Australia through the Centre of Excellence in Science and Innovation program. This support is gratefully acknowledged.
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Information & Authors
Information
Published In
Journal of Geotechnical and Geoenvironmental Engineering
Volume 137 • Issue 12 • December 2011
Pages: 1244 - 1253
Copyright
© 2011 American Society of Civil Engineers.
History
Received: Sep 8, 2009
Accepted: Nov 1, 2010
Published online: Nov 4, 2010
Published in print: Dec 1, 2011
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