Research of the Influence of Various Factors on the Thermal Conductivity of Large-Format Vertically Perforated Clay Blocks

The article is devoted to the description of complex studies of the influence of various factors on the thermal conductivity of samples of large-format vertically perforated clay blocks of domestic production of 6 types different samples. Problems are described when testing the thermal conductivity of large-format vertically perforated clay blocks according to the methods of existing local standards. The research were carried out according to GOST 7076 on a modern equipment, which allowed us to find a number of dependencies. The influence of the following factors on the thermal conductivity of a clay block in a dry state was established: number of rows of voids in clay block, shape of voids, density and thermal conductivity of a ceramic cork. The best thermal values were determined for clay blocks with an HV design of voids, with number of rows of voids more than 6.8 pieces per 100 mm of length and the lowest density and thermal conductivity of the ceramic cork. Separately, it was noted that the presence of large holes for gripping with fingers when installing masonry in blocks has a negative effect on its thermal conductivity. The new results obtained are of great practical importance due to the widespread use of vertically perforated clay block in modern construction. Prospects for further research are described to determine the degree of influence of various factors on the thermal conductivity of clay blocks, to identify the optimal shape of voids, as well as to establish the dependence of thermal conductivity on average temperature and operating humidity.

P.P. PASTUSHKOV^{1, 2}, Candidate of Sciences (Engineering) (This email address is being protected from spambots. You need JavaScript enabled to view it.),
N.V. PAVLENKO^{1, 2}, Candidate of Sciences (Engineering) (This email address is being protected from spambots. You need JavaScript enabled to view it.);
S.I. SMIRNOV³, Engineer (This email address is being protected from spambots. You need JavaScript enabled to view it.)

¹ Scientific-Research Institute of Building Physics of RAACS (21, Lokomotivniy Driveway, Moscow, 127238, Russian Federation)
² Institute of mechanics Lomonosov Moscow State University (1, Michurinsky Avenue, Moscow, 119192, Russian Federation)
³ Association of Ceramic Materials Manufacturers (115477, Moscow, Kavkazsky Boulevard, 20 p. 1)

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