Magnetic Field Effects on Q355B Steel Corrosion Morphology and Helical Anchor Uplift Behavior

This study quantitatively characterized corrosion morphology evolution of Q355B steel under magnetic fields (MFs) using non-contact 3D scanning. MFs exert a threshold-dependent effect on the corrosion morphology and spatial distribution of Q355B steel, while the macroscopic mass loss rate remains largely stable across different MF intensities, the maximum local pit depth peaks at 60 mT, increasing by 42.9%. Spatial autocorrelation shifts from longitudinal long-range to enhanced transverse continuity. Depth distributions follow lognormal distributions. Under uplift, corroded helical anchor bearing capacity varies nonlinearly with MF intensity, reaching a maximum at 30 mT due to the optimal synergy between enhanced surface roughness-induced interface friction and localized cross-sectional reduction. These findings support corrosion assessment and mechanical prediction for Q355B components in MF-coupled environments.