Diagnosis of the surface layer damage in a 1960s reinforced concrete building

• The cortical deterioration of a reinforced concrete building was analyzed through a chemical-physical characterization.
• In some large regions rebars did not present any corrosion, while in other areas degradation was particularly pronounced.
• In these areas cracking and spalling of the concrete cover were the main decays along with corrosion of the steel rebars.
• Concrete poor quality, and the presence of air pollutants and of localized humidity caused the differential decay.

This work aimed to determine the degradation causes of the Palace of Public Works located in S. Giovanni square in Turin (Piedmont, Italy). The samples collected from the surface layer were characterized by means of scanning electron microscopy (SEM), X-ray diffraction (XRD), thermogravimetric coupled with differential thermal analysis (TG-DTA), mercury intrusion porosimetry measurements (MIP) and phenolphthalein test. Metallographic and elemental analyses were also carried out on the steel reinforcing bars. An exhaustive picture of the main causes of deterioration was drawn in order to design the intervention of rehabilitation.