Probabilistic Combination of Forces in Tension Leg Platform Tethers
Publication: Journal of Structural Engineering
Volume 117, Issue 5
Abstract
Tension leg platforms (TLPs) are a class of compliant offshore structures that respond dynamically to ocean winds, waves, and currents. A TLP is tied to the ocean floor by tethers that, due to hull buoyancy, are in tension in the absence of environmental loads. Motions of a TLP lead to additional dynamic forces in the tethers. Also, depending on the deck height, there is a small likelihood of waves impacting the TLP deck. Wave impact induces tether forces that increase rapidly as a function of wave‐immersion distance into the deck. In this study, an extension of the point‐crossing method was used to predict the probability of waves impacting the deck of a TLP. This method was also used to predict the combination of dynamic forces (including wave‐impact loads) acting on a TLP tether. The results are used to calculate the reliability of a TLP tether under maximum tension loads.
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Information & Authors
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Published In
Journal of Structural Engineering
Volume 117 • Issue 5 • May 1991
Pages: 1532 - 1548
Copyright
Copyright © 1991 ASCE.
History
Published online: May 1, 1991
Published in print: May 1991
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