Foam Concretes for Heat Insulation Layers of External Walls Constructed by the Method of 3D Printing

Requirements for conditions of obtaining the material for heat insulation layers of external walls are substantiated with regard to the technology of building 3D printing. The rationality of the use of non-autoclaved cement foam concretes is justified, since the construction and technological process of their production can be integrated with the process of 3D printing of buildings. On the basis of the analysis of structural variants of external walls and thermo-technical calculations, it is shown that the use of ultra-lightweight foam concretes is effective for the construction of effective enclosing structures with a given thermal resistance. The results of studies to obtain foam concretes of average density of 200–400 kg/m³ are presented. It is established that the production of resistant to settling foam concretes of this average density is provided by the use of ultra-disperse fillers with a specific surface area of over 200 m²/kg. The lowest density values are provided at a mass ratio of cement to the filler in the range of 1:1 – 1: 1.5. With an increase in the mass fraction of fillers there is a sharp increase in density characteristic for all the considered types of foam concrete. Taking into account the presence of competing requirements for density and resistance to subsidence, rational compositions of foam concrete based on various types of natural and anthropogenic raw materials are justified. To obtain various types of foam concrete, the grade of the average density and the coefficient of thermal conductivity in the dry state and in the state of natural humidity are statistically reliably determined.

G.S. SLAVCHEVA, Doctor of Sciences (Engineering) (This email address is being protected from spambots. You need JavaScript enabled to view it.)
T.V. MAKAROVA, Candidate of Sciences (Engineering) (This email address is being protected from spambots. You need JavaScript enabled to view it.) Voronezh State University of Architecture and civil Engineering (84, 20-letiya Oktyabrya Street, 394006, Voronezh, Russian Federation)

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