Applicability discussion for multi-peak Gaussian model of corrosion layer at steel/concrete interfaces

The corrosion of the steel bars of two reinforced concrete specimens subjected to different chloride ingress environments for 13 years was evaluated by scanning electron microscopy. A multi-peak Gaussian model has been applied for the distinctive shape of the corrosion layer observed in these systems. The influence of macroscopic voids (10−5–10−2 m in diameter) at the steel–concrete interface (SCI) on the corrosion process and the relationship between the shape of the corrosion layer and the location of the cracks are discussed. The width-to-height ratio Rwh of the corrosion layer is proposed, according to the calculation of coefficients of the multi-peak Gaussian model to describe the shape of the corrosion products at the SCI. The distinctive influence of natural and artificial chloride environment on the corrosion process are quantified by this model, demonstrating the applicability of the model to reinforced concrete exposed for long durations to severed corrosive environments.