Study on the non-uniformity of rust layer and residual rebar caused by pitting corrosion in mortar

Rebar corrosion and non-uniformity in remaining rebar and corrosion products are critical factors influencing the durability of reinforced concrete structures. This study investigates pit corrosion non-uniformity by designing mortar- rebar samples of three different cover thicknesses. The non-uniformity of rebar and corrosion products' distribution is explored using mu CT techniques, and parameter variation laws are derived under different corrosion levels. This study proposes a novel non-uniform rust layer model based on a sine function, which is compared with the existing linear decreasing, semi-elliptic and Gaussian function models. The proposed model provides high goodness-of-fit results and accurately simulates the morphological properties of actual rust layers.