Issue 56

N. Miloudi et alii, Frattura ed Integrità Strutturale, 56 (2021) 94-114; DOI: 10.3221/IGF-ESIS.56.08

Initiation time t ini (years)

Figure 10: Effect of concrete cover, and quality of concrete on initiation time of corrosion.

(a) Environment of moderate aggressiveness Good concrete Ordinary concrete Poor concrete

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25

Necessary section (zone III)

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15

10

5

0

0

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100 150 200 250 300 350 400 Time (years)

2 )

A s (t) (cm

Figure 11: Evolution of residual section of reinforcements as a function of time for different cement contents.

Influence of critical concentration of chlorides The presence of Cl - ions in the vicinity of steel surfaces does not automatically induce corrosion. Accumulation of chlorides until the critical concentration is reached in the vicinity of the reinforcements is necessary for the passive layer

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