Toughening of requirements to buildings’ power efficiency enables development and implementation of modern lightweight concretes on efficient porous aggregates into building industry. The key demands to both lightweight heat-insulating and to fine concretes are ensuring low density index and thus low thermal conduction with high durability provided. There has been developed a lightweight heat-insulating fine concrete mix with the use of three fractions of granulated foam glass. To conduct the research there has been used a central composite design, which helped determine optimal consumption of separate fractions of granulated foam glass, and acquire a lightweight heat-insulating fine concrete with the lowest density. On the basis of obtained research results there has been carried out a calculation of thermal conduction ratio with the use of empirical formulae. The research results have been analyzed, and their descriptive statistics have been presented as diagrams and graphs. On the basis of the analysis of the research results there have been obtained regression equations and established influence degree of separate fractions of granulated foam glass on the density and thermal conduction ratio. There has been carried out an optimization of the material mix and the correlation between fine aggregate fractions calculated to provide the lowest average density.

Keywords: fine concrete, granulated foam-glass, thermal conduction ratio, average density, durability, experiment design, regression, mix optimization

The article considers the relevance of the use of nanomodified concrete in construction. The compositions of the studied mixtures are given, as well as the methods of their preparation using ultrasonic dispersion, the results of the experiment on the destructive effect of standard samples of beams are obtained. The conclusions of the obtained experimental data are presented.

Keywords: concrete, foam concrete, carbon nanotubes, superplasticizer, dispersion

The sedimentation analysis method is based on the measurement of the deposition rate of suspended solids depending on their equivalent diameter. The use of sedimentation for disperse systems is limited by their size, as microscopic dust particles have low deposition rates and are difficult to analyze. Therefore, for finely dispersed systems, the authors propose a method of sedimentation analysis using portable cameras that record the deposition process and break it down into frames. The images obtained frame by frame are translated with the help of a graphic editor into binary (black and white) format, which is able to process the software. The experimental data obtained are presented in the form of tables and distribution functions.

Keywords: sedimentation, dispersion, dust, binary photography, equivalent diameter, cement dust, distribution function

The article deals with the issue of the influence of ambient temperature on the initial height of the flare emissions rise. The paper presents full-scale and theoretical studies of flare emissions operating near a temporary residential complex. In the course of the work, a series of images of flare emissions at different ambient temperature conditions was carried out and their subsequent comparison with the theoretical model was carried out. Field studies verify the theoretical model and establish that the initial height of the flare emissions depends on the ambient temperature and has an inverse proportionality.

Keywords: Flare, flare emissions, atmospheric air pollution, PM2.5

Air pollution in residential areas near industrial plants is one of the most significant problems of modern ecology. The resulting dust is one of the important factors in assessing the adverse impact on the environment. Studies show that the greatest danger to the human body is particles up to 10 microns in size. When analyzing the dispersion of dust in the residential and industrial areas, it is possible to estimate the percentage of particles PM10 and PM2.5 from the total amount that is necessary to effectively control the effects of dust on human health. The article gives a comparative analysis of the results of studies of the dispersion composition and dust concentration in the air of the working zone and the urban environment.

Keywords: sources of pollution, atmospheric air, dispersed analysis, PM10, PM2.5, dust, microscopic method, laser method, concentration, sanitary protection zone