View all text of Subjgrp 112 [§ 250.904 - § 250.908]

§ 250.908 - What are the minimum structural fatigue design requirements?

(a) API RP 2A-WSD, Recommended Practice for Planning, Designing and Constructing Fixed Offshore Platforms (as incorporated by reference in § 250.198), requires that the design fatigue life of each joint and member be twice the intended service life of the structure. When designing your platform, the following table provides minimum fatigue life safety factors for critical structural members and joints.

If . . . Then . . . (1) There is sufficient structural redundancy to prevent catastrophic failure of the platform or structure under consideration,The results of the fatigue analysis must indicate a minimum calculated life of twice the design life of the platform. (2) There is not sufficient structural redundancy to prevent catastrophic failure of the platform or structure,The results of a fatigue analysis must indicate a minimum calculated life or three times the design life of the platform. (3) The desirable degree of redundancy is significantly reduced as a result of fatigue damage,The results of a fatigue analysis must indicate a minimum calculated life of three times the design life of the platform.

(b) The documents incorporated by reference in § 250.901 may require larger safety factors than indicated in paragraph (a) of this section for some key components. When the documents incorporated by reference require a larger safety factor than the chart in paragraph (a) of this section, the requirements of the incorporated document will prevail.

[76 FR 64462, Oct. 18, 2011, as amended at 81 FR 36150, June 6, 2016]