Non-Gaussian Air Gap Response Models for Floating Structures
Publication: Journal of Engineering Mechanics
Volume 129, Issue 3
Abstract
The air gap response of a specific semisubmersible platform subjected to irregular waves is considered. Statistical analyses are performed on model test data for the absolute near-structure wave elevation, and these measured data are compared with predictions resulting from probabilistic models. Models applied are first-order and second-order diffraction models typical of standard practice, and two new hybrid models that include second-order effects in the incident wave, but not in the diffracted wave. The first of these hybrid models is moment based, while the second relies on narrow-band random process theory. Either of these new models can be implemented in place of the standard linear-only model with little additional computational effort, as only linear diffraction analysis is required. Both new models are found to better predict the air gap demand than standard linear diffraction analysis.
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Information & Authors
Information
Published In
Journal of Engineering Mechanics
Volume 129 • Issue 3 • March 2003
Pages: 302 - 309
Copyright
Copyright © 2003 American Society of Civil Engineers.
History
Received: Apr 3, 2001
Accepted: Aug 8, 2002
Published online: Feb 14, 2003
Published in print: Mar 2003
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