## 3 Results
### Thickness and Distribution of Corrosion Products Around the Steel Rebar  
This subsection presents an analysis of the thickness and distribution of corrosion products around the steel rebar. In the measurement of the thicknesses of the corrosion products, the layer representing the transformed medium was not considered. Contrary to expectations, the largest thickness of corrosion products was observed for the impressed current density of 50 \(\upmu\)A/cm\({}^{2}\) and after 14 days (Table 3). For the current density of 100 \(\upmu\)A/cm\({}^{2}\), the overall thickness increased with the duration of the accelerated corrosion test, with the exception of the 21 st day (Table 3). The maximum thickness of  
Figure 8: Half-cell potential (\(E_{corr}\)) and corrosion current density (\(J_{corr}\)) of the RC prisms versus duration of the accelerated corrosion test in the first and second columns, respectively. Data obtained using different impressed current densities: (**a**) 50 \(\upmu\)A/cm\({}^{2}\) (represented by green triangles), (**b**) 100 \(\upmu\)A/cm\({}^{2}\) (represented by blue squares), (**c**) 200 \(\upmu\)A/cm\({}^{2}\) (represented by red circles). corrosion products at 200 \(\mu\)A/cm\({}^{2}\) impressed current density seemed to stabilize quickly (after 3.5 days of accelerated corrosion). Corrosion products may possibly increase rapidly until a threshold value and then stabilize due to the withdrawal of corrosion products along the cracks. The results do not permit showing a clear trend due to the dispersion of corrosion product thicknesses obtained around and along at the steel/concrete interface. Regarding the location of corrosion products, it is obvious that the accumulation of the corrosion products at the steel/concrete interface is not uniform around the rebar, whether along the rebar or inside each Ci area (Table 3). As a general result, the maximum thickness of corrosion products was mainly observed in areas C8, C1, C2 and C3 since they were facing the thinnest concrete covers and the top concrete surface, where the counter-electrode is located. This resulted in the generation of an electrical field that forced chloride ions to migrate to the rebar. Figure 9 shows the boundaries of steel rebar, corrosion products and concrete and illustrates the evolution (kinetics) of the corrosion product formation and location. The corrosion products are barely discernible at the lowest current density (50 \(\mu\)A/cm\({}^{2}\)). An increase in the current density (100 \(\mu\)A/cm\({}^{2}\)) results in the formation of corrosion products with a thickness of approximately 250 \(\mu\)m (Figure 9). It can be observed that the corrosion product thickness at the highest current density (200 \(\mu\)A/cm\({}^{2}\)) is locally larger (exceeding 500 \(\mu\)m), which is in accordance with the results presented in Table 3. \begin{table}
\begin{tabular}{l c c c c} \hline \hline
**RC Prism** & **Minimum Thickness of** & **Location of the** & **Maximum Thickness of** & **Location of the** \\
**Pn-Xd-Y** & **Corrosion Products (\(\mu\)m)** & **Minimum Thickness** & **Corrosion Products (\(\mu\)m)** & **Maximum Thickness** \\ \hline P23-14d-50 & 50 & C2 & 1502 & C2 \\ \hline P25-28d-50 & 29 & C5 & 828 & C8 \\ \hline P27-70d-50 & 23 & C1 & 873 & C2 \\ \hline P31-7d-100 & 22 & C2 and C6 & 736 & C2 \\ \hline P05-14d-100 & 36 & C2 & 827 & C2 \\ \hline P08-21d-100 & 29 & C8 & 617 & C2 \\ \hline P09-28d-100 & 82 & C4 & 1112 & C8 \\ \hline P11-35d100 & 111 & C1 & 1584 & C8 \\ \hline P14-3.5d-200 & 50 & C5 & 1287 & C1 \\ \hline P16-7d-200 & 100 & C6 & 1374 & C8 \\ \hline P17-17.5d-200 & 28 & C4 & 1228 & C3 \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Minimum and maximum thicknesses of corrosion products at the steel/concrete interface and corresponding locations using different impressed current densities (50, 100 and 200 \(\mu\)A/cm\({}^{2}\)). Figure 9: SEM images of the steel/concrete interface showing the thickness of the corrosion products layer for a total charge equal to 168 A.h/m\({}^{2}\).