Air-curing expanded concrete composed of binder-containing mixtures

A method for production of an expanded concrete, the method comprising steps of:

• mixing binder, concrete additives, and concrete liquefiers with one another, to form a binder-containing mixture having binders composed of Portland cement according to DIN EN 197 or of mixtures of binders that bind in a hydraulic, latently hydraulic and/or pozzolanic reaction, wherein the concrete additives comprise microsilica, ground slag sand and/or fly ash, in a proportion of 0.5 to 25 mass % with reference to the mass of the binder and the concrete liquefiers are present in a proportion of 0.05-5 mass % with reference to the mass of the binder,
• adding to the binder-containing mixture a chemical propellant, in the form of an aluminum powder at 0.05-0.25 mass % with reference to the mass of the binder for the formation of air pores, whereby the aluminum powder comprises a mixture of aluminum particles having different particle sizes, the aluminum particles having different particle sizes being completely dispersed with one another in water before being added to the binder-containing mixture, and
• adjusting the mixture to a concrete consistency of at least the consistency class F4 according to DIN 1045-2, at a beginning of binding reactions in the binder-containing mixture, by adding water,
• wherein the expanded concrete produced inothis manner is chemically expanded by the chemical propellant, forming air pores of different sizes and of homogeneous distribution, and hardens under atmospheric pressure at ambient temperature, by hydration of the binder,
• wherein the expanded concrete comprises a matrix having a distribution of air pores, the air pores having different sizes,
• wherein the expanded concrete has a compressive strength of up to 30 N/mm2 after curing, and
• wherein the compressive strength of the expanded concrete depends on a mortar consistency of the expanded concrete and on the distribution of the air pores.