Installation of Torpedo Anchors: Numerical Modeling
Publication: Journal of Geotechnical and Geoenvironmental Engineering
Volume 135, Issue 12
Abstract
Torpedo anchors are used as foundations for mooring deep-water offshore facilities, including risers and floating structures. They are cone-tipped cylindrical steel pipes ballasted with concrete and scrap metal and penetrate the seabed by the kinetic energy they acquire during free fall through the water. A mooring line is usually connected at the top of the anchor. The design of such anchors involves estimation of the embedment depth as well as short-term and long-term pullout capacities. This paper describes the development of a computational procedure that leads to prediction of torpedo-anchor embedment depth. The procedure relies on a computational fluid dynamics (CFD) model for evaluation of the resisting forces on the anchor. In the model, the soil is represented as a viscous fluid and the procedure is applied to axially symmetric penetration of the seabed. The CFD approach provides estimates of not only the embedment depth but the pressure and shear distributions on the soil-anchor interface and in the soil.
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Acknowledgments
This research was made possible with support from the UNSPECIFIEDU.S. Department of Interior’s Minerals Management Service and the Offshore Technology Research Center.
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Information & Authors
Information
Published In
Journal of Geotechnical and Geoenvironmental Engineering
Volume 135 • Issue 12 • December 2009
Pages: 1805 - 1813
Copyright
© 2009 ASCE.
History
Received: Jun 6, 2008
Accepted: May 25, 2009
Published online: May 29, 2009
Published in print: Dec 2009
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