Improving Plate Anchor Design with a Keying Flap
Publication: Journal of Geotechnical and Geoenvironmental Engineering
Volume 140, Issue 5
Abstract
Suction embedded plate anchors have been increasingly applied in deepwater projects because of their efficiency and limited cost. Current industry practice equips the fluke of the anchor with an outwardly rotating keying flap aiming at a reduction of the loss of embedment during keying. However, recent experimental and numerical research has questioned the efficiency of the keying flap currently used in practice because it has demonstrated that the flap does not open during keying as was intended. This paper presents a two-dimensional plain strain large deformation finite-element analysis by assuming the soil as homogenous to investigate the performance of plate anchors equipped with various keying flap designs. The results of the paper agree with previous centrifuge and finite-element analysis that the outwardly keying flap has no effect on the loss of embedment and results in a reduction of the bearing capacity postkeying. The performance of an alternative keying flap design where the flap is rotating inward is also discussed. The new design effectively reduces the loss of embedment during keying and exhibits a bearing capacity higher than the current design.
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Acknowledgments
This research was undertaken with support from the Australia-China Natural Gas Technology Partnership Fund and the Lloyd’s Register Foundation (LRF). The LRF, a U.K.-registered charity and the sole shareholder of Lloyd’s Register Group, invests in science, engineering, and technology for public benefit worldwide. This study comprises part of the activities of the Centre for Offshore Foundation Systems, currently supported as a node of the Australian Research Council Centre of Excellence for Geotechnical Science and Engineering. The helpful discussions with Professor Mark Randolph are much appreciated.
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Published In
Journal of Geotechnical and Geoenvironmental Engineering
Volume 140 • Issue 5 • May 2014
Copyright
© 2014 American Society of Civil Engineers.
History
Received: Mar 20, 2013
Accepted: Jan 4, 2014
Published online: Jan 28, 2014
Published in print: May 1, 2014
Discussion open until: Jun 28, 2014
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