The Effect of Seabottom Proximity of the Vortex-Induced Vibrations and Fatigue Life of Offshore Pipelines

The effect of the seabottom proximity on the vortex-induced vibrations of suspended spans of offshore pipelines is discussed in the light of recent relevant experimental results. It is shown that the effect of the seabottom proximity is to drastically alter the vortex-induced vibrations of supsended spans resulting into longer fatigue lives or equivalently longer safe lengths. A “generalized” fatigue damage is formulated universally applicable to all suspended spans.