A Stress-Corrosion Model to Simulate Degradation Process of Steel Structure in Marine Environment

Abstract Stress corrosion cracking poses a threat to the service safety and structural performance of steel structures in marine environments. Based on Peridynamics theory, a stress corrosion model is proposed, considering the dual mechanisms of stresspromoted corrosion dissolution and corrosion-accelerated fracture. To capture the heterogeneity of corrosion damage, a random bond-breaking algorithm is introduced, and a method for identifying both corrosion and mechanical damage is proposed based on the material’s chemical corrosion and fracture processes. The model’s validity is verified through comparison with experimental results. Based on this model, the effects of loading rate, pre-corrosion hole diameter, and corrosion dissolution coefficient on the failure mode, damage parameters, and mechanical properties of steel plates under stress in chloride ion corrosion environments are analyzed. The results show that a lower loading rate extends the corrosion time, leading to a larger corrosion damage area and significantly reducing yield strength. The pre-corrosion hole radius influences the damage failure mode and yield strength by changing the corrosion contact area and effective bearing area. The corrosion dissolution coefficient affects yield strength by adjusting the corrosion rate and duration.