PROBABILISTIC FATIGUE ANALYSIS OF FIXED OFFSHORE STRUCTURES

This paper describes the application of probabilistic techniques to the detailed determination of local stress histories, thus permitting a detailed member-by-member fatigue analysis of fixed offshore structures. Using a suitable static or dynamic structural analysis program, the transfer functions for hot spot stresses at four points around each member end in the structure are generated as a function of wave frequency and direction. For each given sea state and wave direction, short-term stress statistics at the hot spots are calculated from the associated wave spectrum and transfer function. The resulting short-term stress statistics in all the yearly sea states in the wave scatter diagram, and for given probabilities of occurrence of the various wave directions, are then combined to yield long-term stress statistics at each hot spot. Finally, Miner's cumulative damage law is applied to evaluate local fatigue damage.

• Supplemental Notes:
  • Presented at the Eighth Annual Offshore Technology Conference, Houston, Texas, May 3-6, 1976.
• Corporate Authors:

  Offshore Technology Conference

  6200 North Central Expressway
  Dallas, TX  United States  45206
• Authors:
  • Vughts, J H
  • Kinra, R K
• Conference:
  • Presented at the Eighth Annual Offshore Technology Conference, Houston, Texas, May 3-6, 1976.
• Publication Date: 1976-5

Media Info

• Features: References;
• Pagination: p. 889-906

Subject/Index Terms

• TRT Terms: Loads; Mechanical fatigue; Offshore structures; Structural analysis; Structural mechanics; Water waves
• Old TRIS Terms: Wave loads
• Subject Areas: Bridges and other structures; Hydraulics and Hydrology; Marine Transportation; Materials;

Filing Info

• Accession Number: 00138234
• Record Type: Publication
• Source Agency: Offshore Technology Conference
• Report/Paper Numbers: V2, OTC 2608 Proceeding
• Files: TRIS
• Created Date: Aug 23 1976 12:00AM