Fatigue analysis on multi-spanning pipelines

Pipelines are used on the seabed for long periods of time,so the fatigue life of the pipeline is important.In considering this issue,pipeline fatigue life was investigated.The method of calculation of the load was obtained by analysis of the environmental load of a multi-spanning pipeline.Following that,the fatigue models of in-line and cross-flow vortex induced vibration(VIV) were investigated and the fatigue life of multi-spanning pipelines could be obtained.The in-line and cross-flow multi-modes of pipelines were calculated by the finite element method(FEM),making it possible to acquire the dynamic characteristics of the pipelines.In the end,the effects of different span lengths and soil types on the fatigue life of pipelines were illustrated.Consequently,this analysis of pipelines may provide useful information for further investigation on pipelines.