Abstract
To investigate the coupled effects of cable corrosion on the ultimate strength and fatigue performance of cable-stayed bridges, sophisticated numerical simulations incorporating established corrosion mechanisms were conducted. Corrosion-induced degradation was modeled through cross-sectional area reduction and material property deterioration, with specific emphasis on wire elongation capacity attenuation. Three finite element models representing steel cable-stayed bridges with distinct spans (300 m, 600 m, and 900 m) were subjected to progressive collapse analysis and fatigue assessment. The results indicate that: (1) Structural failure consistently manifested through plastic hinge formation and fracture at the mid-span girder across all models, accompanied by partial plastification at the tower base; (2) Increased span length elevated cable stress at failure, thereby amplifying the influence of cross-sectional area reduction on ultimate strength; (3) Reduction of wire elongation rate from 4% to 3% or 2% resulted in marginal ultimate strength reductions, whereas attenuation to 1% induced precipitous capacity decline; (4) Under concurrent minimum cable area and elongation rate conditions, the ultimate load-bearing capacity of all bridge configurations experienced an approximate 50% reduction; (5) Corrosion significantly compromised fatigue performance at all cable positions, with localized pitting corrosion exacerbating stress concentration effects and accelerating cross-sectional degradation, consequently diminishing fatigue life.