Journal of Marine Science and Technology

, Volume 13, Issue 3, pp 308–315 | Cite as

Confidence bounds on structural reliability estimations for offshore platforms

Original Article
First Online:
Received:
Accepted:

Abstract

Second-order estimates to measure platform reliability are generated and used to provide an additional space to select safety margins appropriate to the owner's perception or for risk-averse managers. The aleatory and epistemic uncertainties in the parameters of an offshore platform are explicitly considered in the reliability analysis and the platform structural reliability becomes a random variable, assessing then the beneficial effects of a reduction on these uncertainties. One of these benefits is for risk-aversive managers who often demand additional room to make conservative decisions regarding reliability estimations. Proposed here is a procedure to generate the frequency diagram of platform reliability with the use of confidence bounds to support reliability and cost decisions based on percentiles instead of mean values. The concepts are illustrated through a typical offshore platform in Mexico. The frequency diagram of the platform reliability index is built for several alternative designs and three levels of epistemic uncertainty. The results may be applied for decision making on new designs and also on the assessment and optimal inspection, retrofit, and decommissioning of existing platforms.

Keywords

Epistemic uncertainty Structural reliability Risk management Offshore platforms 
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Notes

Acknowledgments

The results for the offshore platform illustrated in this paper were based on data from the IMP and PEMEX of Mexico. The authors are thankful for the opportunity to use these data in this study.

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Copyright information

© JASNAOE 2008

Authors and Affiliations

  1. 1.Autonomous University of Mexico StateTolucaMexico
  2. 2.University of CaliforniaIrvineUSA

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