Numerical modeling of pipe-soil interaction under surface loading

Abstract

Buried steel pipelines (BSPs) subjected to large surface-induced ground movements (e.g., fault displacements) exhibit complex behavior that is not yet fully understood. Such ground-induced deformations give significant risks to pipeline integrity, motivating detailed investigation into BSP response under extreme conditions. This study addresses the problem by numerically modeling pipe–soil interaction under a 1.0 m vertical fault displacement, illustrating the pipeline’s stress–strain response and highlighting the challenges of this complex engineering scenario. The purpose of this paper is to demonstrate a robust simulation approach that captures the intricate BSP behavior under large ground shifts, thereby advancing understanding and aiding in the safe design of buried pipelines. The analysis employs a Pasternak elastic foundation model coupled with a finite element method (FEM) in Abaqus, using special pipe–soil interaction (PSI) elements to simulate the soil support and pipeline coupling. The numerical results provide detailed stress and displacement distributions along the pipeline, confirming an elastic–plastic deformation pattern. Permanent deformations (plastic yielding) develop primarily in the vicinity of the fault, while pipeline regions farther than roughly 100 m remain in the elastic region.