Fatigue reliability analysis of vortex-induced vibration of submarine pipeline span

In view of the submarine pipeline spans being vulnerable to considerable fatigue damage over its design life period due to the dynamic excitation caused by vortex-induced vibration (VIV) under wave and current, the reliability analysis method of nonlinear vortex-induced vibration fatigue failure of pipeline spans was proposed. The VIV equation was solved by the Galerkin method. Then fracture mechanics approaches were adopted to assess the fatigue reliability. In the assessment of fatigue failure the uncertainties associated with the parameters and procedures employed for the fatigue damage estimation were considered. The effects of some important factors on the fatigue failure of pipeline span was analyzed. Finally, based on the fatigue crack propagation theory, the fatigue reliability analysis method of pipeline span was established. By calculating an example, the applicability and reliability of the method were validated.