ABSTRACT
As far as the penetration of chloride through the concrete cover is concerned, the complex nature of transport of chloride in concrete has led to the use of simplified procedures. Chloride profiles can be reasonably described by means of the relationship:
C(x, t) = Cs [
1 − erf (
x
2 √
Dt
)] (1)
where: C(x, t) is the chloride concentration at depth x and time t, Cs is the chloride content at the surface of concrete and D is the diffusion coefficient (Collepardi et al., 1970). This relationship is a solution of Fick’s second law of diffusion, but it is used by most of design models even for exposure conditions where the transport of chloride is also driven by other transport mechanisms, such as suction, and an apparent diffusion coefficient (Dapp) is introduced (Bertolini, 2008).
