Some aspects of improvement of physical and mechanical characteristics of heat-insulating foam concrete

The article presents the results of a series of experimental studies aimed at obtaining heat-insulating foam concrete with D500 density with improved physical and mechanical characteristics due to the selection of the type of aggregate, the combination of its fractions and the use of low-energy-intensive activation by alternating electrophysical effects. An analysis of the results showed that the highest efficiency of low-energy foam activation is achieved by using ground sand fractions up to 0.16-0.315 mm. The strength of foamed concrete on ground sand is higher than that of foamed concrete on rounded sand and on screening of crushed stone. At the same time, the greatest jump in the strength of activated foam compared with non-activated foam is observed when using ground sand fractions of 0.08-0.16 and 0.16-0.315 mm. The joint use of two different fractions provides a more compact packing of particles in the interpore walls, which also contributes to an increase in the strength of foam concrete. The average density of activated foam when using small fractions of sand is slightly less than that of non-activated. A series of experimental studies has proved that using the most rational prescription factors and activation by a low-energy-intensive alternating electric field with optimal parameters improves the physical and mechanical characteristics of foam concrete.