Research Activities – Carbonation

Department of Materials and Rheology

Due to growing pollution of the atmosphere especially by carbon dioxide the durability of prefabricated cement-based housing is decreasing. Carbonation is a chemical process in which carbon dioxide diffuses to the depth of concrete element and reacts with alkaline components in the cement paste mainly calcium hydroxide. As a result of these reactions the carbonation products are formed and phase composition and cosequently properties of concrete are changed. Likewise, the alkalinity of related cement paste is decreasing. This fact is assessed by phenolphtalein test. In this case violet part represents part of concrete with higher alkalinity (pH > 9.5). Contrary, the additional parts are carbonated with low pH value.

Fenolftalein test of carbonated concrete specimens