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The article analyzes the properties changes of non-autoclave foam on a protein foaming agent with the introduction of dispersed wollastonite and diopside. A decrease in the density of foam concrete (to the grade D300, D400), frost resistance of the material, as well as shrinkage deformations was noted. The optimal technological parameters have been determined, allowing to obtain more stable properties and structure of heat-insulating cement-ash non-autoclave foam concrete. The flow chart of the production of foam concrete of natural hardening in the separate preparation of foam and mortar is presented. The studies were performed at NSTU and NGASU (Novosibirsk) and the NII (Norilsk).

Abstract. Foam concretes are used as effective heat-insulating materials. The porous structure of foam concrete provides good insulating and strength properties that make them possible to be used as heat-insulating structural materials. Optimal structure of non-autoclaved foam concrete depends on both technological factors and properties of technical foam. In this connection, the possibility to manufacture heat-insulation structural foam concrete on a high-speed cavity plant with the usage of protein and synthetic foamers was estimated. This experiment was carried out using mathematical planning method, and in this case mathematical models were developed that demonstrated the dependence of operating performance of foam concrete on foaming and rotation speed of laboratory plant. The following material properties were selected for the investigation: average density, compressive strength, bending strength and thermal conductivity. The influence of laboratory equipment technological parameters on technical foam strength and foam stability coefficient in the cement paste was investigated, physical and mechanical properties of non-autoclaved foam concrete were defined based on investigated foam. As a result of investigation, foam concrete samples were developed with performance parameters ensuring their use in production. The mathematical data gathered demonstrated the dependence of foam concrete performance on the technological regime.

An effective method for increasing the aggregate stability of non-autoclave heat-insulating foam concrete is proposed. This material is prepared using a two-stage technology on a turbulent-type installation. An increase in the stability of the foam in the mortar mixture by 9.5-23% has been established. An increase in the viscosity of the foam concrete mixture by 13.5% was revealed. Wollastonite and diopside are actively involved in the formation of a stable structure of foam concrete and are structurally modifying centers. The introduction of mineral additives contributes to the formation of a homogeneous stable structure of non-autoclave foam concrete. Thus, an increase in the stability of the cellular system in the technology of non-autoclave cement-ash foam concrete is possible due to the control of the processes of structure formation when using dispersed mineral additives of wollastonite and diopside. Due to the structural-modifying effect of additives as crystallization centers for neoplasms, a more complete hydration of the cement and a strong contact of the additives with the cement stone should be ensured