Dauerhaftigkeit von Porenbeton bei hoher CO2-Beaufschlagung

Durability of autoclaved aerated concrete under high CO₂ impact.

Ordinary autoclaved aerated concrete (AAC) (P2-0,35) was stored under different humidity conditions and a constant CO₂ atmosphere of 1 % by volume. Additionally, AAC samples with a good and poor phase formation were produced and included into the weathering procedure. In addition to the artificial CO₂ weathering, ordinary AAC was stored under rain protection outdoor for a period of 3 years. After storing the samples under different conditions and periods, the material was measured for its raw density, compressive strength and mineral phase content. The outdoor stored AAC was tested after 3 years for its thermal conductivity. Boundary conditions such as material moisture and drying behaviour of the AAC as well as ambient moisture, influence the material properties within the weathering procedure. Artificial CO₂ weathering leads to other effects than natural weathering. AAC with well crystalline tobermorite does not change its compressive strength or thermal conductivity under natural climate conditions. A negative long-term development of the material properties can be excluded.