Characterization of Carbonatation Rate of Alkali-Activated Blast Furnace Slag in Various Environments

Abstract

Carbonatation represents one of the potential degradation processes whose can negatively affect the service life of constructions based on the inorganic binders. The carbonatation depth of the constructions when exposed to various environments is significantly dependent on the existing conditions. The most crucial parameters are the partial pressure of carbon dioxide and humidity. There were selected four environments for the deposition of samples made of the alkali-activated blast furnace slag mortars (exterior, interior, water and CO2 chamber) in this study. These types of environments guarantee the variation of desired parameters influencing the carbonatation rate. The progress of carbonatation was evaluated with a selected technique in time intervals of 28; 56 and 84 days of the sample's exposition to the selected environments. The characterization was done using the destructive techniques (compressive and flexural strength, phenolphthalein method) as well as the non-destructive one like the Impact-Echo or the Ultrasound time passage measurement. The combination of these techniques allows to determine and evaluate the progress of carbonation without the destructive testing of the samples which is necessary for the real applications of these materials.