Dynamic stability of submerged pipelines

The paper considers the dynamic stability of submerged pipelines with denudation and sagging depending on their stiffness and the river flow rate. The hydrodynamic force frequency and natural vibrations of the pipeline are calculated at the actual and critical length of the pipeline sagging. It is shown that the frequency of the external hydrodynamic force applied to the sagged pipeline with the length corresponding to the critical, coincides with the frequency of natural vibrations. It is found that the loss of stability of submerged pipelines occurs in the resonant region of the pipeline vibration due to the increased variable hydrodynamic force.

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