Modelling upheaval buckling in marine buried pipelines by coupling the shear stresses and soft soil stiffness

• Published in: Marine structures 2023-09, Vol.91, p.103475, Article 103475
• Main Authors: Cuamatzi-Meléndez, Ruben, Salazar-Martínez, M., Montoya, D.J., Hernández-Noriega, M.
• Format: Article
• Language: English
• Subjects: Pipelines; Shear stresses; Soft soil stiffness; Upheaval failure
• ISSN: 0951-8339; 1873-4170
• DOI: 10.1016/j.marstruc.2023.103475

Buried marine pipelines employed in the Oil & Gas industry are subjected to pressure and temperature gradients, which cand produce local high compression loads leading to the onset of upheaval buckling failure. Upheaval buckling occurs when the localized stresses across the pipeline are high enough to induce constant deformation due to the low soil restriction in the upward direction. Therefore, models to predict upheaval buckling in buried marine pipes caused by high pressure and high temperature (HP/HT) and soil stiffness have been developed based on Euler-Bernoulli beam theory (EBT). However, this theory does not consider stresses and strains due to shear stresses which can play an important role in upheaval buckling failure. Therefore, in this work an analytical model that takes into account Engesser-Timoshenko beam theory (TBT) and considers the shear effects on pipelines was developed to predict upheaval buckling in buried marine pipelines. Furthermore, equations that govern vertical buckling of buried pipelines considering a plastic soil with initial imperfection were considered. Analytical results were compared with finite element models of buried pipeline and other models reported in the literature, and it was observed that analytical results fall in the range of those reposted in the literature. It was also observed that the incorporation of shear stresses in buried marine pipelines has low effect on upheaval buckling onset and propagation, but the soil stiffness has a strong influence on upheaval failure in buried marine pipelines. •This work integrates shear stress effect and soil stiffness to model upheaval in buried marine pipelines.•The work contributes to the prediction of upheaval buckling in buried marine pipelines.•Analytical and finite element analyses may provide a better understanding of upheaval failure of buried marine pipelines.•The results showed the levels of upheaval that can occur in buried marine pipelines.