Buckle Propagation in Submarine Pipelines

Abstract

A relatively simple approach is first presented for the approximate analysis of the collapse of circular rings under external pressure. It accounts for geometrical and material nonlinearities, and is able to approximate the precollapse and postcollapse behaviors of rings. Applications of the approach to selected rings are made, and the resulting solutions are shown to be in good agreement with those of accurate finite element analyses. An examination is then made of the relationship between the ring‐collapse problem and the buckle‐propagation phenomenon in submarine pipelines, leading to an improved understanding of the phenomenon and to the development of a simple expression for the associated buckle‐propagation pressure. Relevant information and concepts of structural behavior are also reported, which are useful for practical applications. Predictions of the developed expression for the buckle‐propagation pressure are shown to be in good agreement with available experimental data, and it is proposed that the expression be used for design purposes.