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http://dx.doi.org/10.12989/sem.2003.16.3.317

Reliability of TLP tethers under extreme tensions  

Siddiqui, N.A. (Department of Civil Engineering, Aligarh Muslim University)
Ahmad, Suhail (Department of Applied Mechanics, Indian Institute of Technology)
Publication Information
Structural Engineering and Mechanics / v.16, no.3, 2003 , pp. 317-326 More about this Journal
Abstract
The tension leg platform (TLP) is a moored floating offshore structure whose buoyancy is more than its weight. The mooring system, known as tethers, is vulnerable to failure due to extreme (maximum and minimum) tensions. In the present study the reliability of these tethers under maximum and minimum tension (ultimate limit state) has been studied. Von-Mises failure criteria has been adopted to define the failure of a tether against maximum tension. The minimum tension failure criteria has been assumed to meet when the tethers slack due to loss of tension. First Order Reliability method (FORM) has been adopted for reliability assessment. The reliability, in terms of reliability index, and probability of failure has been obtained for twelve sea states. The probabilities of failure so obtained for different sea states have been adopted for the calculation of annual and life time probabilities of failure.
Keywords
structural reliability; TLP; offshore; ultimate limit state; tethers;
Citations & Related Records

Times Cited By Web Of Science : 2  (Related Records In Web of Science)
Times Cited By SCOPUS : 3
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