| Summary: | The method and low-energy intensive technology of manufacturing products of foamed concrete are developed providing bringing-in a solar energy in technological conversion for reducing the energy consumption for heat treating, allowing to obtain high quality products at low cost with a diurnal cycle of production. Thereby, the use of a minimal amount of additional electrical energy is stipulated for providing a consistence of temperature fields in the cross section of helio heated products in landfills in combination with solar energy. Until now, many scientists have investigated the issues of using the renewable energy resources in the construction industry including solar ones, for replacement of conventional fuels applied in the thermal treatment of concrete products and structures. However, pursuant to the analysis of the scientific literature, all known research studies and developments in this area are devoted to heliothermal treatment of conventional concrete, and at the same time the traditional methods for acceleration of hardening requiring significant energy consumption are still in use in production of such an effective building material as foam concrete. There are various methods of heliothermal treatment including combined ones, but they are not applicable in their production due to the specific characteristics (unlike conventional concrete) of manufacturing technology, the used components, the particular rheological properties, as well as a porous structure of foam concrete. Both the examining the use of solar energy in acceleration of foam concrete hardening according to the literature data and the pre-studies have revealed a problem under unilateral heliothermal treatment of foam concrete. It is found out that the temperature field of across thickness of the massif, especially during the first 7-8 hours, is irregular, that significantly affects the process of heating moisture transfer occurring within the massif. According to the previously obtained data, there is the highest uniformity of moisture distribution efficiency and thereby a maximum strength uniformity of products under bilateral supply of heat to the hardening concrete. On this basis, it is advisable to use both solar and additional electric energy having impact of periodic and short duration on the hardening concrete for the intensification of the foam products hardening in landfills in order to ensure a uniform heating of products and reducing temperature gradients. Calculations showed that the duration of landfill operation on production of foam concrete products for the areas of Central Asia located in 46° N is 8 months per year, i.e. from March to October. In order to achieve the greatest effect in the process of applying the developed method for complex heliothermal treatment of foam concrete products, there is a need in a steady warm and clear weather when the ambient temperature at noon reaches the values higher than +20 °C. It is found out that high strength characteristics can be achieved under optimum combination of exotherm of cement in foam concrete with soft modes of warming-up and cooling down of products.
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