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The research results of the composition, properties and structural features of bottom ash waste from the Trans-Baikal Territory were presented to determine the possibility of their use in road construction. It was stated that bottom ash waste are non-frost heaving. The indicator of specific effective activity of natural radionuclides was determined SEA (226Ra, 232Th, 40K) for samples of pulverized ash and ash and slag mixtures, which was less than 370 Bq/kg and indicated the possibility of their use in road construction without restrictions. The hydraulic properties of pulverized ash were identified that characterize them as latently active, and ash and slag mixtures as inert materials, which limits the possibility of their use as a separate binding agent. The conclusion was made about the need for an integrated approach to a targeted change in the physical and mechanical properties of ash and slag waste including the use of various mineral binders and stabilizing additives to include waste in the composition of road materials.

The anthropogenic impact on environment of ash and slag waste of CHP 1 and CHP 2 (Chita) and CHP Priargunsky Industrial Mining and Chemical Union (Krasnokamensk) is considered. These wastes cause irreparable damage to the environment, occupy a significant area, lead to a deterioration of the environmental situation in the surrounding areas. Liquidation of such objects of accumulated harm to the environment is the most important state task in the areas of national economy and environmental protection. Rapid recycling of ash and slag waste is possible in road construction (the main material-intensive sector of the national economy) due to large-capacity direct use. This will effectively reduce the anthropogenic impact on the environment and significantly reduce the use of mineral raw. The principal possibility of using of fly ash as a secondary mineral raw material in compositions of road soil concrete is substantiated. The methods of atomic emission spectrometry with inductively coupled plasma, differential scanning calorimetry and thermogravimetry were used to study the composition and properties of fly ash of CHP, which is a first-class mineral raw based on the specific effective activity of natural radionuclides (226Ra, 232Th, 40K), which allows their use in the construction industry without restrictions. It has been established that fly ash is non-porous, its hydraulic properties are classified as latent-active and can be added to road cement soils modified with additives of different nature.

The possibility of utilization of inactive fly ash in road concrete compositions by bringing of ash into a non-equilibrium condition with increased reactivity by mechanical activation in a vibration eraser is investigated. It was revealed that the optimal content of binder and fly ash in samples of soil concrete was 8 and 10 wt. %, respectively. It is shown that, due to mechanical activation, the specific surface area of fly ash increases by 2 times, dehydration and carbonization occur and silicon is replaced by aluminum in silicon-oxygen tetrahedra. It has been established that an increase of the content of crystalline carbonate phases is the reason for an increase in the strength of ground concrete. It is determined that the introduction of mechanoactivated fly ash into the composition of soil concretes contributes to increasing their physical and mechanical characteristics to the maximum strength grade M100. This indicates the competitiveness of ground concrete and the possibility of direct use of inactive fly ash in road construction.