The present work shows the progress of an ongoing research where, the influence of SiO₂ –based nanoparticles (Nbs) ingress into hardened concrete specimens through the curing on the electrochemical behaviour of concrete-steel system was evaluated. For this, prismatic specimens of reinforced concrete were fabricated with two w/b ratios: 0.3 and 0.7. A suspension of 0.1 and 0.3% (by weight) of Nbs in water was applied during curing of specimens in periods of 1, 3 or 7 days.

Then, samples were separated in two different environments for at least 28 days: immersion in tap water and in laboratory conditions. Subsequently, specimens were exposed to penetration of chlorides using wetting and drying cycles as a simulation of conditions in a marine environment. The main techniques to evaluate the behaviour of embedded steel in specimens in this period were electrical resistivity, corrosion potential and linear polarization resistance. Also, chloride content and pH values of matrix concrete were assessed several times.

It was found, that the introduction of Nbs in hardened concrete can react with the cement matrix reducing its permeability, therefore, this phenomenon could get a great influence on initiation and propagation corrosion time.