Upheaval buckling of buried offshore pipelines -

Abstract

Offshore pipelines are used to transport oil and gas in different areas of the world. The economic importance of offshore pipelines has increased in recent years with the development of oil and gas transportation systems. Hydrocarbons are transported in the pipelines at high temperature and pressure in order to facilitate the flow of oil and to prevent its “solidification”. However, these high temperatures and pressures may force the pipeline to buckle either in the horizontal (lateral) or in the vertical direction (upheaval). The latter buckling mode may lead to pipeline failure that could cause massive oil leakage and severe environmental damages. Several studies have investigated the uplift resistance of buried pipelines. The objective of this thesis is to assess the effects of several parameters (soil burial depth, soil and pipeline properties and geometries) on the upheaval buckling of buried offshore pipelines by using the finite element software Abaqus to build the 3D model considering all pertinent factors. A new simplified empirical design approach is presented based on the parametric studies and analytical solutions explored and-or developed in the thesis herein.