Analysis of buried pipelines subjected to ground surface settlement and heave

Abstract

This paper presents an analytical methodology for the calculation of internal forces and strains developing in continuous buried pipelines that cross geotechnically problematic areas and are susceptible to permanent ground surface settlement or heave. Material nonlinearity effects are introduced in the solution via an iterative procedure, while taking into account the effect of pipeline elongation on its response. The use of a versatile bilinear expression to describe the stress-strain response of the pipeline material renders the method appropriate for steel, high-density polyethylene (HDPE), concrete, and cast iron pipelines alike. Comparison of the analytical results against those from benchmark finite element analyses highlights the effectiveness of the simplified analysis. The method is a potential alternative to elaborate three-dimensional nonlinear numerical analyses that are often used in pipeline design practice, and offers ease-of-use with no expense in accuracy, at least for problems involving simple pipeline geometries.