ON EXPERIMENTAL PREDICTION OF LOW-FREQUENCY OSCILLATIONS OF MOORED OFFSHORE STRUCTURES

This report discusses the effect which different methods of simulating an irregular seaway has on the ability to predict second order behaviour of moored offshore structures by model tests. A theoretical discussion of the problem is given. This is followed by the experimental results obtained from model tests of an offshore platform subjected to different simulated irregular seaways. These were produced by the two main methods of simulation applied today. One is to superimpose a finite number of regular wave trains. The other consists in filtering white noise so as to obtain a time series with the correct spectral shape, usually in the form of an electric signal, which is then used to guide a wave maker. The conclusion to be drawn from the obtained results is that the second method of simulating an irregular seaway gives us the most reliable estimate of the second order behaviour of moored offshore structures.

• Supplemental Notes:
  • Paper presented at the 9th Annual ITC in Houston, Texas, May 2-5 1977.
• Corporate Authors:

  Offshore Technology Conference

  6200 North Central Expressway
  Dallas, TX  United States  45206
• Authors:
  • Naess, A
  • Borresen, R
• Publication Date: 1977

Media Info

• Features: References;
• Pagination: p. 7-18
• Serial:
  • Publication of: Offshore Technology Conference
  • Publisher: Offshore Technology Conference

Subject/Index Terms

• TRT Terms: Force; Moored structures; Moorings; Offshore moorings; Simulation; Waves
• Old TRIS Terms: Irregular waves; Oscillating mooring systems; Wave forces on structures
• Subject Areas: Bridges and other structures; Design; Marine Transportation;

Filing Info

• Accession Number: 00158023
• Record Type: Publication
• Source Agency: Offshore Technology Conference
• Report/Paper Numbers: V3, OTC 2879 Proceeding
• Files: TRIS
• Created Date: Aug 15 1977 12:00AM