Rebar corrosion is a leading cause of degradation in reinforced concrete （RC） structures， particularly in coastal environments. This study investigated the corrosion-induced cracking mechanism of concrete cover， focusing on the localized accumulation of corrosion products （rust peaks） at the steel-concrete interface due to inherent defects. Micro-computed tomography （µCT） was employed to perform a non-destructive， three-dimensional analysis of rust peaks forming at the steel-concrete interface. A three‑dimensional rust peak fitting model based on a two‑dimensional Gaussian function was proposed， and its accuracy was verified with experimental data. Based on this model， the relations between rust peaks and natural interface defects were examined， and a corrosion-induced cracking model for the cover was established. The findings revealed that the crack width increased significantly with the growth of rust peak height， and specimens with thinner concrete cover were more prone to developing distinct cracks. The model demonstrated high prediction accuracy in laboratory testing， with most prediction errors remaining within 15%. These results provide theoretical support for understanding structural degradation induced by rebar corrosion in engineering practice， although their applicability in complex environments still requires further verification.
Jiang et al. (Wed,) studied this question.