The limits of reliability theory and the reliability of limit state theory applied to pipelines
Two distinct concepts have been developed in general structural engineering and are now being applied to pipelines. Limit state thinking focuses on conditions that directly threaten the security or operability of a system, and have already been adopted into several codes applicable to offshore pipelines. Reliability theory attempts to quantify the safety of a system by statistical arguments. The paper examines how far limit state methods can be exploited in marine pipeline engineering without underpinning them by reliability theory. It explores this application of reliability theory, and suggests that in this instance -- as in many others -- the data needed for confidence are not available (and in many instances can never by available). As in structural failures generally, a majority of pipeline failures are beyond the reach of reliability theory. Paradoxically, this fact may strengthen the case for the adoption of less conservative requirements on limit states, because the real increase in risk is often zero or extremely small. These arguments are then applied to a discussion of the allowable circumferential stress in pipelines, where traditional design factors have often been copied from code to code.
- OSTI ID:
- 434033
- Report Number(s):
- CONF-960525-; TRN: IM9709%%467
- Resource Relation:
- Conference: 28. offshore technology conference, Houston, TX (United States), 6-9 May 1996; Other Information: PBD: 1996; Related Information: Is Part Of 28. annual offshore technology conference: Proceedings. Volume 4: Field drilling and development systems; PB: 942 p.
- Country of Publication:
- United States
- Language:
- English
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