Finite-Element Analysis of Pipelines with Axial Walking and Lateral Buckling

Abstract

A pipeline is prone to axial movement, called pipeline walking, under heat-up and cooldown cycles. The build-up of axial force along the pipeline can result in the phenomenon referred to as lateral buckling. Walking and lateral buckling can both influence pipeline movement performance and threaten the safety of pipeline systems. The numerical simulation method is adopted to study the pipeline movement laws under walking and buckling interactions. Walking and buckling interactions are classified into three types for different forms of seabed slopes, and corresponding mitigation methods are proposed. The effects of buckling number, route bend, sleeper spacing, and anchor position on the lateral displacement amplitude, axial displacement, and effective axial force (EAF) of the pipeline are analyzed. Criteria for the mitigation methods are proposed based on parameters such as the pipeline end expansion, buckling failure parameter, maximum anchor force, and minimum compressive EAF. The results show that the anchor position has a great influence on the intertransformation of pipeline buckling and walking. The difference in anchor force can reach 51.1% considering different anchor positions.