Mustafa Alhusain
Purpose This study aims to investigate the elastic hoop stress response of pressurized steel pipelines containing full-circumference longitudinal corrosion defects, with an emphasis on stress amplification, axial redistribution and the spatial extent of the disturbed region. Design/methodology/approach A three-dimensional finite element model of a straight pipeline segment subjected to internal pressure was developed. The corrosion defect was idealized as a region with uniform wall thinning. A parametric analysis was conducted for six normalized defect lengths (Ld/D = 0.05 − 2) and four depth ratios (a/t = 0.1 − 0.4). Inner- and outer-surface hoop stresses were extracted to evaluate the axial stress distribution, peak stress, stress concentration factors and recovery length based on the defined tolerance limits. Findings The defect depth governs the magnitude of stress amplification, whereas the defect length mainly controls whether the peak stress becomes fully developed. The maximum inner-surface stress reached 156.8 MPa (1.65 times the intact value), whereas the outer-surface stress increased to 108 MPa (1.27 times the intact value). Peak stresses became insensitive to defect length beyond Ld/D ≈ 0.5 at the inner surface and Ld/D ≈ 0.25 at the outer surface. The axial disturbance was strongly localized, with the hoop stress recovering within approximately 0.09–0.16D at the inner surface and 0.04–0.08D at the outer surface based on a 5% tolerance σθ/σθ,intact≤1.05. Originality/value This study provides a mechanics-based characterization of elastic stress amplification and localization associated with longitudinal wall thinning under service-level loading.