The concept of sustainability requires that waste-modified materials also demonstrate adequate sustainability. This paper examines the effect of modifying cement concrete with waste lime dust on the course of concrete carbonation. The waste dust comes from the dedusting of aggregate for use in HMA – Hot Mixture Asphalt. The aim of the study was to examine whether the partial replacement of sand with waste powder would have a negative effect on the potential durability of a reinforced concrete element made of this concrete. To determine the extent of carbonation, an experimental plan was prepared including the execution of concretes with varying levels of substitution and a variable water/cement ratio. In order to identify long term influence the test was performed as indicated in EN 12390-12, but with the test time extended to 560 days. The results obtained were statistically analysed and the predicted maximum extent of carbonation depending on the level of substitution and the water/cement ratio was determined. The analysis indicates that it is possible to substitute sand with waste limestone dust without having a negative impact on the extent of carbonation, and thus on the durability of the reinforced concrete structure.

The article discusses the physical and chemical mechanisms of the carbonation phenomenon itself, as well as points out the synergistic effect of frost destruction and concrete carbonation on reinforced concrete elements. Examples of structural damage from engineering practice in the diagnosis of reinforced concrete structures are presented. Two cases of frost and carbonation damage of precast reinforced concrete elements are analyzed. It was noted that the most common cause of damage to concrete structures is the lack of frost resistance. Carbonation of concrete leads to deprivation of the protective properties of the concrete lagging against the reinforcing steel. The examples cited include precast elements that, for technical reasons, had a relatively small lagging thickness. The first one relates to the thin walled elevation elements, which are exploited during 60 years and the second relates to the energetic poles with very advanced concrete corrosion damage. The examples given of corrosion of concrete and reinforcement of elements indicate that synergistic environmental interactions can intensify the destruction of elements.