A comprehensive failure analysis of corroded high-strength steel pipelines under seismic-induced landslide

In this work, a nonlinear finite element (FE) model was developed to investigate the synergistic effect of corrosion and seismic-induced landslides on the failure behavior of high-strength steel pipelines. This work integrated a permanent ground deformation (PGD) function and uniform corrosion modeling methodology. The failure mechanism, process, and path of high-strength steel pipelines under the action of corrosion, internal pressure, and landslide displacement were investigated. Findings indicated that the landslide impact caused significant stress concentrations at the corrosion defect, triggering failure. The corroded pipeline exhibited 8–54 % higher maximum von Mises stress in comparison with the intact pipeline. Among the defect parameters, corrosion depth (d/t = 0.1–0.5) had a more substantial impact on the pipeline's structural integrity than corrosion length (l/$\sqrt{\mathrm{Dt}}$=0.5–2.5) and width (CW = 0.01–0.05). The combined effects of landslides, corrosion, and internal pressure further accelerated pipeline failure. Additionally, failure was most likely to occur at the defect site when the defects was located circumstantially at the landslide-opposing side (95^o), and axially at the shear area center or near the landslide area center. In other cases, the failure location shifted to a pipe's undamaged area at the landslide center.