New Results and Methodological Developments on Thermal Conductivity Research of Autoclaved Aerated Concrete of Modern Production

The article is devoted to the description of comprehensive research of the thermal conductivity of autoclaved aerated concrete of modern production in the entire range of density grades on the newest testing equipment in the Russian Federation, as well as methodological developments that were obtained during these studies. The dependences of thermal conductivity on the density of autoclaved aerated concrete at an average temperature of 10 and 25^оC, as well as the approximate ratio of these characteristics to each other, are obtained. The degree of influence of the sample size on the result of thermal conductivity measurements recorded by the device is established. The linear dependence of thermal conductivity on operational humidity has been confirmed and the coefficients of thermal quality of autoclaved aerated concrete have been found. A “correction” has been established for the set of humidity of autoclaved aerated concrete samples during thermal conductivity tests and a method for finding it has been described, which can be used in industry regulatory documents. The convergence of the results of thermal conductivity tests obtained on samples in the form of flat square plates and on whole blocks has been established. At the same time, it is concluded that tests on samples in the form of square plates are more technologically advanced and reproducible, so they should remain the main ones for evaluating the thermophysical characteristics of autoclaved aerated concrete.

P.P. PASTUSHKOV^{1, 2}, Candidate of Sciences (Engineering) (This email address is being protected from spambots. You need JavaScript enabled to view it.)

¹ Research Institute of Building Physics Russian Academy Architecture and Construction sciences (21, Lokomotivniy Driveway, Moscow, 127238, Russian Federation)
² Institute of Mechanics Lomonosov Moscow State University (1, Michurinsky Avenue, Moscow, 119192, Russian Federation)

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