Considerations on the Design of Keying Flap of Plate Anchors
Publication: Journal of Geotechnical and Geoenvironmental Engineering
Volume 139, Issue 7
Abstract
One of the critical issues associated with plate anchor performance and design relates to the reduction of the loss of embedment during the keying process. As deep water offshore sediments typically exhibit an increasing soil strength with depth, the loss of embedment results in a reduction in anchor bearing capacity. A keying flap hinged to the main plate has been developed and adopted by industry with the aim to reduce the loss of embedment by limiting the vertical motion of the anchor. However, uncertainties remain regarding the behavior and the performance of the keying flap. This paper presents a series of numerical analyses performed to investigate the flap rotation mechanism and the condition of activation of the flap. They are compared with existing centrifuge modeling. The numerical results validate the centrifuge observations and demonstrate the nonactivation of the keying flap for typical anchor pull-out conditions.
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Acknowledgments
This research is being undertaken with support from the Australia-China Natural Gas Technology Partnership Fund and the Lloyd's Register Foundation. The work forms part of the activities of the Centre for Offshore Foundation Systems (COFS), currently supported as a node of the Australian Research Council Centre of Excellence for Geotechnical Science and Engineering and through Centre of Excellence funding from the State Government of Western Australia.
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Information & Authors
Information
Published In
Journal of Geotechnical and Geoenvironmental Engineering
Volume 139 • Issue 7 • July 2013
Pages: 1156 - 1164
Copyright
© 2013 American Society of Civil Engineers.
History
Received: Aug 15, 2011
Accepted: May 14, 2012
Published online: May 17, 2012
Published in print: Jul 1, 2013
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