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!

SSCS 2012

On behalf of the M3C4 team, Branko took part in the first international conference "Sustainable Strategies for Concrete Structures", held in Aix-en-Provence, France. Dedicated mainly to numerical modelling and its impact on sustainable concrete structures and materials, the conference was a big success. Many significant researchers were there, and presented their work. As our team also presented a paper, usefull feedback from colleagues was obtained. On the other hand, this city has proven to be a very nice and pleasant place for such an event. Following the success of the conference, it is rumoured that the following one is going to take place in Rio de Janeiro, Brazil. The M3C4 team is looking forward to that!