Production of
AAC concrete using the
MC-AirTec process

There are a number of factors that influence the production of AAC concrete of exposure classes XF2 to XF4, making it difficult to precisely control the air injection process and achieve the required air void content.

Until now, air-entraining agents have been added to the concrete in the main mixing process and must then be broken down by the frictional forces during the mixing process. In addition to effective mixing technology, this also requires a sufficiently long mixing time to ensure that the air-entraining agent is fully activated. Air-entrained concrete therefore generally requires significantly longer mixing times than other types of concrete.

The MC-AirTec process

In the MC-AirTec process, the air-entraining agent Centrament AirTec is weighed as standard. In contrast to the usual addition method, however, it is not dosed directly into the mixer, but is passed through the MC-AirTec generator in advance, where it is foamed in a special process. This creates very fine micro-air pores that are characterised by high stability. This fine foam contains very stable micro-pockets, which are then introduced into the premixed concrete, enabling fast and even distribution. In this way, the required quantity of air voids is precisely adjusted and a high-quality aerated system is created in the concrete, one that offers outstanding characteristics (density 300 and air void spacing factor).