Foamed concrete is usually composed of cement or a slurry of fly ash, sand and water, although some suppliers recommend mixing pure cement and water with foaming agents for lightweight mixtures. The slurry is further mixed with synthetic aerated foam in concrete mixing equipment. The foam is made by mixing a foaming agent with water and air produced by the generator. The blowing agent used must be able to generate bubbles with a high level of stability, and be able to resist the physical and chemical processes of mixing, placing and hardening.
The foamed concrete mixture can be poured or pumped into the mold, or directly into the structural element. Due to the thixotropy of the foam bubbles, the foam allows the slurry to flow freely, making it easy to pour it into the selected form or mold. Viscous materials can take up to 24 hours to cure (if steam curing is performed at temperatures up to 70°C, it can take up to 2 hours to cure), depending on the ambient temperature and humidity. After curing, the molded product can be released from the mold. A new application in foam concrete manufacturing is to cut large concrete cakes into different sizes by using a special steel wire cutting machine. When the concrete is still soft, the cutting action occurs.
Foamed Concrete are used in bridge approaches / embankments, pipeline Abandonment / annular fill, trench backfill, precast blocks, precast wall elements / panels, cast-in-situ / cast-in-place walls, insulating compensation laying, insulation floor screeds, insulation roof screeds, sunken portion filling, trench reinstatement, sub-base in highways, filling of hollow blocks, prefabricated insulation boards and much more.