Foam concrete and preparing process thereof

The invention discloses foam concrete and a preparation method thereof. The foam concrete comprises a gelling material, light aggregate, water, admixture and foaming agent. The preparation method comprises the following steps: (1) pre-treating raw materials to prevent hard lumps and hard grains in the raw materials from depositing in foam slurry; (2) weighing each component according to a proportion; (3) preparing and adding foaming solution; (4) loading and stirring, namely, adding water into a stirrer, starting the stirrer, and adding cement, coal ash, perlite, waterproof agent, anti-freezing agent, water reducing agent and fiber into the stirrer in turn; (5) foaming, namely, foaming at the same time of stirring the slurry, sealing a valve firstly and then pressurizing the valve by an air compressor; (6) adding foam, namely, after the gelling slurry is well prepared, adding the foam into the gelling slurry under the state of stirring without stopping the stirrer; and (7) casting and molding, namely, when the slurry surface has no floating foam, finishing the preparation of the foam slurry. The foam concrete has the functions of light weight, water proofing, fire resistance, heat insulation, freezing resistance, cracking resistance, shock resistance and the like, and is particularly suitable for engineering insulating layers in cold areas and water-blocking and shock-resistant layers of underground engineering.