BUCKLE PROPAGATION AND ARRESTING IN OFFSHORE PIPELINES

A summary is presented of recent developments that contribute to reliably predicting the magnitude of the buckle propagation pressure for deep-water offshore pipelines. The associated problem of buckle arresting is then addressed, and a study is made of the relationship between the external pressure and the buckle length for conditions representative of those involved in the arresting of a propagating buckle. Using energy methods, an analytical expression that defines that relationship is obtained, and it is shown that its predictions are in very good agreement with those of accurate finite element solutions. The relationship between the pressure and the buckle length reported herein could be useful in improving the understanding of the forces exerted by a buckle on an arrestor during a buckle arresting process. Furthermore, an examination is made of the magnitude of the dynamic effects induced on an arrestor by a propagating buckle, and it is demonstrated that such effects are usually small.