Analytical Model for Vertically Loaded Anchor Performance
Publication: Journal of Geotechnical and Geoenvironmental Engineering
Volume 140, Issue 1
Abstract
Vertically loaded anchors (VLAs) are installed in a manner similar to drag-embedded anchors, except that after initial drag installation the anchor shank is released to enhance pullout capacity. Because of their lightness and relatively low installation cost, VLAs offer an attractive alternative for mooring systems. However, existing design procedures are largely empirically based, and uncertainties with regard to anchor trajectory and load capacity have limited their application to temporary mooring systems. This paper presents a design model for predicting VLA performance during drag installation, shank release, and subsequent loading beyond the installation load. Model-based parametric studies on the effects of VLA fluke–shank angle and anchor line angle at the mudline are also presented. Some aspects of the model have been benchmarked against limited available field data, but a broader validation is still needed.
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Acknowledgments
The authors acknowledge the support of the Joint Industry Project, which was operated for the participants by ABS Consulting, and especially John Stiff of ABS for his assistance and encouragement throughout the effort. The authors also acknowledge the support of the Offshore Technology Research Center and their colleagues at the University of Texas.
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Information & Authors
Information
Published In
Journal of Geotechnical and Geoenvironmental Engineering
Volume 140 • Issue 1 • January 2014
Pages: 14 - 24
Copyright
© 2014 American Society of Civil Engineers.
History
Received: Dec 2, 2012
Accepted: Jun 4, 2013
Published online: Jun 6, 2013
Published in print: Jan 1, 2014
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