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Troubled concrete foundations are a serious issue but Ralph Tulis believes that the issues facing companies like J.J Mottes Co. will eventually be revealed to be something that no one knew about. Tulis points out that during the time when this defective concrete was created not much was known about the effects of pyrite and pyrrhotite.

He then points out that two the known deterioration mechanisms are alkali silica reaction and the other involves the presence of pyrrhotite in the coarse aggregate (stone) used to produce concrete, which take 8-15 years or more to become evident. He also takes a look how these issues can possibly be mitigated:

We do not yet know what specific conditions foster the deterioration. I have seen foundations whose concrete came from a single source yet only portions of the foundation show evidence of the suspected pyrrhotite deterioration. I do not believe that the mere presence pyrrhotite alone is the sole cause, as it (and pyrite) are minerals commonly found in varying concentrations in igneous rock.

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