PSI - Issue 64

Fritz Binder et al. / Procedia Structural Integrity 64 (2024) 175–182 Fritz Binder/ Structural Integrity Procedia 00 (2019) 000 – 000

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Fig. 6: Corrosion current and the derived cumulative corrosion rate over time on column #17 repaired with hydrophobic treatment.

Fig. 7: Density plot (left) and boxplot categorized into seasons (right) before (pre) and after (post) repair treatment with coating of column #03.

Fig. 8: Density plot (left) and boxplot categorized into seasons (right) before (pre) and after (post) hydrophobic treatment of column #17.

The measured corrosion potentials (see Fig. 3 and Fig. 4) indicate a high corrosion risk overall. Lower corrosion activity observed only in summer and early autumn. This trend is present in all measured potentials, most pronounced at column #17 (see Fig. 4). The corrosion potentials clearly vary with temperature, showing differences up to 30 mV, and lack of humidity seems to increase this trend. After repair, the potential steadily increases to around -300 mV. The hydrophobic treatment leads to more favorable corrosion potentials by promoting drying and preventing chloride penetration. In contrast, after the repair with coating, an increase in measured corrosion