Corrosion rates of steel in cracked concrete

Cracks in concrete cover allow fast penetration of aggressive substances such as chlorides, leading to reinforcement corrosion. In the Figure 1, corrosion rates of embedded reinforcing bars in concrete with transverse cracks with widths ranging from 135 to 375 microns are shown. It seems that crack width has an effect on the  evolution of corrosion rate in laboratory conditions.

Figure 1. 

In Figure 2 corrosion potentials are shown, providing indication of the thermodynamical condition of the steel reinforcement. One interesting effect is found on crack width of 217 microns. Although potentials are significantly less noble than the rest, corrosion rates were found to be the lowest of all specimens. It is clear that the experimentation must go on, but so far interesting results have been obtained!

Figure 2. 

More results to be posted soon!