Ohhhhh .... that was written by PCA. Now I understand! Just ignore all of the physical and practical evidence! Go with the obscure chemist's explanation! All you have to do is make perfect concrete! It's not the fault of concrete that nobody can get it exactly right! Can't those ignorant contractors and engineers ever do anything right?!?So I got currious and did some digging... found this interesting article.
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Cement & Concrete FAQ - Portland Cement Association
Your basic cement and concrete questions answered by qualified experts.www.cement.org
It does state that iron corrosion is a major issue but it also says that if done right...
Concrete and the Passive Layer
Although steel’s natural tendency is to undergo corrosion reactions, the alkaline environment of concrete (pH of 12 to 13) provides steel with corrosion protection. At the high pH, a thin oxide layer forms on the steel and prevents metal atoms from dissolving. This passive film does not actually stop corrosion; it reduces the corrosion rate to an insignificant level. For steel in concrete, the passive corrosion rate is typically 0.1 µm per year. Without the passive film, the steel would corrode at rates at least 1,000 times higher (ACI222 2001).