Abstract：In cable structures, the coupled corrosion-fatigue failure mode of steel wires is a common and critical form of failure. However, due to the presence of protective sheaths, corrosion and fatigue do not occur synchronously, posing challenges for failure analysis. Traditionally, methods based on damage mechanics and fracture mechanics have been widely used in the analysis of fatigue fracture. However, damage mechanics methods are limited in engineering practice due to their complexity, while fracture mechanics methods are often based on the premise of the existence of pre-cracks.To overcome the limitations of existing studies, this paper first employs the S-N curve of high-strength steel wires under non-corrosive conditions to evaluate the fatigue damage state of steel wires when the protective sheath is intact. Subsequently, utilizing a corrosion kinetics model, the growth of corrosion pits in steel wires after damage to the protective sheath is calculated, and the critical fatigue cycles for the transition of corrosion pits to cracks are predicted. Based on this, the crack propagation is further analyzed using fracture mechanics principles and the Franc3D software, which facilitates the prediction of the fatigue life of steel wires.To validate the accuracy of the above theoretical calculations, this paper also designs and implements an experiment on the coupled effect of fatigue and corrosion fatigue in high-strength steel wires, with fatigue preceding corrosion. By comparing the experimental results with the theoretical predictions, a small error is observed, thereby verifying the correctness and effectiveness of the proposed theoretical calculation method.In summary, the failure analysis theory proposed in this paper for steel wires in cable structures under coupled corrosion-fatigue failure mode is not only simple to calculate and easy to apply, but also aligns well with experimental results. It provides an important reference for the design, operation, and maintenance of cable structures.
2025, Vol. 46 
