Migration and Concentration of Chlorides, Sulfides and Alkali Compounds in Concrete Caused by Carbonation

Abstract

The facts that chlorides and sulfides fixed inside concrete are dissociated in the form of ions as carbonation progresses and migrate toward the interior of the concrete, an uncarbonated zone, so that parts of very high concentration are formed locally, and that alkali metal ions also migrate have been disclosed through area analyses by an electron probe microanalyzer. As a result of these analyses, it was shown that there is a possibility for deterioration of concrete structures to occur because the action of carbonation releases corrosive factors which had been fixed in the interior even in cases where penetration of corrosive factors does not occur from outside.