The paper presents a new approach to assessing the level of contamination with heavy metals of the soil-like fraction from landfills using Monte Carlo simulation using the example of landfills located within the borders of Volgograd.It was found that with a probability of 36.2%, the contamination level of a soil-like fraction from the landfill located in the Voroshilovsky district will correspond to moderately hazardous, and with a probability of 63.8%, hazardous. It is economically justified to isolate a soil-like fraction with a low level of pollution to detoxify it and further use it in the territory reclamation. For a soil-like fraction from landfill located in the Traktorozavodsky district, the pollution level was determined as extremely hazardous and hazardous with a probability of 87.1% and 3.1%, respectively. It is shown that a useful and usable part cannot be isolated from a soil-like fraction. A soil-like fraction must be neutralized and placed at waste disposal facilities.The presented approach is a useful instrument for pollution level assessment of a soil-like fraction, which can increase the accuracy of an estimate and the management effectiveness of a soil-like fraction during landfill development.

Keywords: landfill, soil-like fraction, heavy metals, pollution level, Monte Carlo method, modeling

The influence of secondary crushed stone on the strength and shrinkage of concrete was studied. The results showed that when granite coarse aggregate is replaced with crushed recycled concrete, the compressive strength of concrete is reduced by an average of 20% and the flexural strength by 3-10%. Concrete on recycled crushed stone has a high shrinkage. The shrinkage of concrete with a minimum consumption of recycled aggregate differs slightly from the shrinkage of concrete on granite crushed stone.

Keywords: demolition waste, concrete scrap, recycling, recycled aggregate, compressive strength, flexural strength, shrinkage

Reliable and safe operation of oil and gas pipelines in the conditions of the Far North and Siberia is an urgent task facing the Russian Federation. It has the most important economic and strategic importance. The climatic and geological conditions of these regions suggest a high degree of risk associated largely with seasonal temperature fluctuations and oil pumping technologies, leading to freezing or thawing of the soil, the appearance of thawed permafrost waters. The purpose of our study was to analyze the influence of extreme natural and operational conditions on the design and spatial position of pipelines during the operation of the section of the CPS-2 - NPS Urengoyskaya highway. It was found out that the studied section of the oil pipeline has a predisposition to failures due to unfavorable conditions: meltwater, heaving soils, swampy territory. Technological calculations allowed us to conclude that at this stage the pipeline route meets all the conditions of strength and stability, i.e. the reliability of the pipeline is ensured.

Keywords: hydrocarbons, pipeline, melt water, underground laying, strength calculation, stability calculation, permafrost soils, spatial location

The article considers the information modeling of the building frame of a complex shape in the plan. The Dynamo program for Autodesk Revit is used to build the geometry. The main goal was to achieve uniform color pressure maps when blowing a building using simulation modeling in an Autodesk CFD PC. The research method is numerical (finite element method). The LIRA-CAD software package was used. The finite element method was used to select the shape of the building and adjust its design scheme to achieve reliability and efficiency. The analysis of the structural elements of the object on the effect of wind loads, taking into account the pulsation component of the wind load, is carried out in order to improve the design decisions made.

Keywords: information modeling, finite element method, building frame, node system, modal analysis, waveforms

The article provides overview information on the importance of ensuring the environmental safety of environmental sulfur, on factors designed to counter the adverse effects of pollutants on the urban environment, aimed at creating comfortable living conditions for the population, and protecting the living environment from the harmful effects of transport. Information is provided on trends in increasing the anthropogenic impact of greenhouse pollution on climate change, Decree of the President of the Russian Federation (dated October 26, 2023 No. 812) on the approval of the climate doctrine, which will be the direction for further research into greenhouse pollution from motor vehicles, data from background stations of the Russian Federation are presented on the increment of CO2 concentrations in the surface layer and in the atmosphere, on the volume of greenhouse gases from the transport flow. Motor transport is indicated as the most influential factor in urban environmental pollution and the negative impact of polluted air on public health in Volgograd. The results of field studies of the intensity of vehicle traffic along the newly commissioned highway “0-th Longitudinal” in Volgograd are presented, a trend of growth in overall intensity, starting from 2019, and an increase in the intensity of low-capacity public transport along newly designed routes are revealed. The directions of necessary research to reduce the environmental impact on the ecology of the coastal zone are shown.

Keywords: diversification of management, production diversification, financial and economic purposes of a diversification, technological purposes of ensuring flexibility of production

The article deals with the improvement of structural solutions of steel reinforced concrete slabs with external reinforcement. The possibility of creating an orthotropic steel reinforced concrete slab on a profiled deck with a continuous or discrete puff located perpendicular to the direction of corrugations is determined. This kind of construction works in bending in two directions along the wave and across the wave. This will allow slabs to be supported on three and four sides, which will make it possible to redistribute the pressure on the supports and reduce the stress concentration at the joints between the slab and the support structure. A continuous puff is assumed to have the same cross-section along its entire length, while a discrete puff can have a variable thickness. Two variants of the calculation of this structure are found, as a monolithic rod with a sprengel chain and as a composite rod with an explicit contact zone. When the stiffness of the contact zone is close to absolute, the rod can be considered as a monolithic rod. An experimental study of the characteristics of the contact zone of the profiled deck organised by means of stamping on the inner side of the corrugation is required, taking into account the perpendicular location of the corrugations to the span of the beam and the concrete part of the section. A comparative analysis of the existing techniques has been made and further experimental investigation methodology has been determined. A numerical evaluation of stresses in a steel plate has been carried out.

Keywords: steel reinforced concrete slabs, orthotropic slabs, calculation methods, contact zone, stamping

The influence of the type and dosage of some redispersible polymer powders on the shrinkage deformation of building mortars obtained from dry building mixes, including for underfloor heating, after exposure at a temperature of 70 ° C in accordance with GOST R 56387-2018 was investigated. The introduction of admixtures 4042N, E06RA, 5603 into the mixtures did not lead to an increase in shrinkage deformations when maintained according to GOST R 56387-2018 relative to the additive-free standard, regardless of the type and dosage of the admixture, while with these admixtures, regardless of their dosage, within 1-3%, the values of shrinkage deformations were less than 1.5 mm / m. The greatest influence of the type and dosage of the redispersed polymer powders on the shrinkage change is manifested at the heating stage, which is due to their influence on the kinetics of dehydration and the magnitude of the E-modulus. Depending on the type of cement, type and dosage of the admixture, the moisture loss values by the end of heating to 70oC ranged from 0.114 to 0.629 relative to the total moisture loss by the end of holding. Naturally, a change in shrinkage by the end of heating from 0.027 to 0.595 relative to complete shrinkage by the end of aging was noted, while a proportional relationship between moisture loss and shrinkage was revealed. In some formulations, an expansion of up to 0.469 mm/m was recorded by the end of heating. For a comprehensive assessment of the degree of influence of admixtures on changes in the deformation and strength properties of mortar at a holding temperature of 70 ° C according to GOST R 56387-2018, an indicator of the conditional stress level is proposed, varying depending on the holding stage, type of cement, type and dosage of the additive in the range from 0.489 to 3.05.

Keywords: Shrinkage, building mortars, dry building mixes, redispersible polymer powders, underfloor heating

The world's reserves of renewable energy sources are steadily declining, but the comfort of life in modern society should remain at the same level. The modern solution of the problems of thermal protection of facade systems of buildings is associated with the analysis of the specific heat capacity of the materials included in their composition. The use of new energy-efficient materials is becoming especially relevant. Such materials include vacuum thermal insulation panels, which significantly reduce heat loss in comparison with traditional thermal insulation.

Keywords: energy efficiency of buildings, thermal protection of facade systems, thermal insulation, vacuum thermal insulation panels, construction production

This article considers the problem of determining the temperature field near a heat-loaded source in the form of a dipole field. Solving this problem will make it possible to identify general patterns of distribution of the temperature field as one moves away from the source. This will make it possible to ensure the normal functioning of powerful electronic components by ensuring the required intensity of heat flux removal, mainly in close proximity to a heat-loaded source, that is, in the zone of maximum heat flux density.

Keywords: numerical methods, energy saving, heat engineering, thermal conditions of equipment, heat-loaded source, near zone, numerical modeling, temperature field, thermal processes, finite element method

The problem of a comprehensive assessment of the quality of construction production is considered. The problematic nature of such a procedure is noted, due to the fact that construction production is a multifactorial process in which a large number of material, financial and labor resources are used, with different units of measurement. It is proposed to consider the complex indicator "Integral indicator of the quality of construction production" based on the transformed Harrington desirability function, which allows taking into account many factors having different-sized controlled parameters.

Keywords: quality of construction production, integral index of construction quality, quality coefficient, generalized utility function, Harrington desirability function

The dynamic system of the grinding machine is simulated, taking into account tool wear. The purpose of the simulation is to improve the algorithmic support of an active control microprocessor device. The vibration characteristics of the SIW-5 machine ring support have been studied at idle and during processing to determine the vibration level at the moment when the grinding wheel touches the workpiece. An algorithm for maintaining the cutting speed with a decrease in the diameter of the circle due to wear has been developed and modeled. characteristics of the ring support of the SIW-5 machine at idle and during processing for the development of algorithms for controlling the grinding process.

Keywords: grinding, bearing rings, active control, mathematical model of grinding, algorithmic support

The paper presents a study of the resistance of connections of load-bearing laminated wood structures using domestic melamine-urea-formaldehyde adhesives (MMFC) to cyclic temperature and humidity influences. The method of cyclic tests is described. An assessment is made of the resistance of MMFC to temperature and humidity influences and the compliance of the selected adhesive with the requirements established for the production of long-span load-bearing structures.

Keywords: melamine-urea-formaldehyde adhesives, wooden structures, resistance of adhesive joints to cyclic temperature and humidity influences, strength

The technological process of manufacturing self-adhesive radio-absorbing materials is considered. The technological mode of manufacturing radio-absorbing materials consists of two operations – the preparation of a mixture and the production of radio-absorbing materials from the resulting mixture. An important step is mixing the mixture. The quality of the radio-absorbing material depends on the quality of the mixture.

Keywords: mixture, mixing time, scanning probe microscope, microstructure study

The paper considers the problem of the arrangement of the abutments of newly erected driveways and roads of agricultural production enterprises to existing roads and driveways. When connecting the "pies" of the roadways of the projected driveways with the existing landscaping, it is necessary to solve the problem of preventing cracking in the coating at the places of the thickness difference of the structural layers. In the article, this problem is solved both from the technical side, by ensuring the joint work of the new and existing road structure, and from the normative one by assigning the projected passage to the IVB category road, in accordance with SP 37.13330.2012, which allows the construction of a road with curbs without curbs and, as a consequence, without storm sewers and sewage treatment plants.

Keywords: road network, cadastral boundaries, the design of the widening of the passage, the technical solution of the junction of roads, transverse profile

The paper considers the opportunities and obstacles to the integration of renewable energy sources (RES) in megacities on the example of Moscow. The paper analyzes the applied RES-based generation technologies, taking into account their applicability in large cities. Special attention was paid to the conversion of unused historical dams into small hydroelectric power plants (SHPP) as an integration of RES in megacities. Based on the results of the technical and economic analysis, it was found that the conversion of an unused dam on the Yauza River into a SHPP is justified.

Keywords: small hydropower, unused dam, megacity, renewable energy integration