Novosibirsk State University of Architecture and Civil Engineering

The paper presents mathematical simulation of reversible filtration of air flow through a thin-walled plastic tubular heat exchanger with an internal diameter of 3.2 mm, taking into account the phase transition at positive outdoor temperatures. The temperature profiles of the air and the checkerwork material have been obtained in various cross-sections. Analysis of the results has shown that the displacement of the phase transition zone along the length of the checkerwork significantly affects the temperature characteristics of the air flow. As the indoor temperature increases (from 10 to 17°C), the zone of influence of the phase transition shifts to the colder end of the setup, changing the air temperature profile. The study has shown that the phase transition affects the air temperature, while its position along the length of the checkerwork determines this effect.

Introduction. The use of nanomaterials and nanotechnology represents one of the most important areas in global scientific and technological development. Nanotechnology involves the controlled regulation of the properties of objects at the molecular and supramolecular level, which determine most of the fundamental parameters and properties of physical objects, based on the targeted manipulation of their atoms and molecules. In hydraulic engineering, this involves the use of nanomaterials and technologies that improve the properties of building materials and structures, increasing their durability and resistance to external influences. Methods and materials. The Novosibirsk Reservoir is a unique multi-purpose water facility. For more than 60 years, it has been intensively used for national economic purposes-it is a source of water supply, the main recreation area for residents of Novosibirsk, the Novosibirsk Region, and the Altai Territory, and is used for navigation and fisheries. There are 41 settlements located within a two-kilometer zone of the reservoir's coastal strip, including the cities of Kamen-na-Obi, Berdsk, Iskitim, and Ordynskoe. The forested coastal area is home to health resorts, cottage and dacha settlements, and gardening communities, as well as a place for short-term recreation for the population. In this regard, the recreational load on the coastal zone of the reservoir is very high, partly due to the steepness of the banks. Various methods are used to calculate the design of shore protection hydraulic structures on water bodies, which take into account, first of all, the natural conditions and characteristics of the water body's shoreline. The results of the calculations are verified and refined on the basis of field studies and, if necessary, laboratory tests and experiments. Results. The paper presents calculations for determining the design parameters of the structure, such as: wind surge height, wave run-up height, top elevation of the structure, scour in front of the stone bank, design composition of the stone bank, and parameters of the stone bank. Discussion. Currently, there are many varieties of nanoscale additives and nanomodified materials. The possibilities for implementing modification mechanisms are determined by the type, characteristics, and dosage of nanoscale particles. As a suggestion, the authors propose to pay attention to the use of geogrids with different cell sizes and nanomodified concretes. However, it should be noted that at present, even with a low required content of nanomodifying additives (2-3% of the total mass of concrete), the addition of such additives will significantly increase the cost of the material. A comparison of technical and economic indicators in this case will clearly indicate this disadvantage and, as a result, the impossibility of using this option for economic reasons. Conclusion. One of the most important criteria for assessing the prospects for the introduction of nanotechnological innovations in the construction industry is their final cost. Nanomodifiers for concrete and building mortars at a price of $100 per gram, even though their strength properties increase by 30%, are unlikely to be in demand. Most of the experts agree that nanostructuring should be applied to widely used materials, including concrete, metals, and fiber-based composites. These breakthrough technologies can be applied in many areas, including hydraulic engineering, strengthening concrete foundations of gas transmission systems, creating flexible plastic geogrids, selecting and creating new high-quality fillers for them, etc. Also, thanks to new nanomaterials, it is possible to produce metal that will last an order of magnitude longer than modern samples. There are sufficient scientific developments in this area. Now it is necessary to find practical applications for them. However, this vector of development entails the need for production re-equipment, staff training, and so on.

Introduction. Precast reinforced concrete ribbed slabs are broadly used as floors and coverings for industrial, residential and public buildings. Their use in this capacity is due to the high technological efficiency of manufacturing, efficient use of concrete and the possibility of automating factory production. One of the critical tasks in designing such structures is to calculate the bearing capacity of normal cross sections. Traditional calculation methods are reliable, but they are outdated. Machine learning methods are increasingly being employed in engineering, where researchers are opting for artificial neural networks (ANNs). The use of traditional methods in processing structured data such as tables and databases has its limitations. Neural networks are capable of analyzing unstructured data such as text, images, and videos, which opens up new prospects for analyzing and comprehending information. The article sets forth an approach to neural network modeling of the bearing capacity of normal sections of prefabricated reinforced concrete ribbed slabs. Materials and Methods. A structured and processed data array (dataset) includes 20 samples for which a computational model based on a multilayer perceptron has been developed and verified. The input parameters are the geometric as well as physical and mechanical characteristics of the slabs and the applied load, the output parameter is the limiting bending moment calculated using the limit state method. Research Results . Training on a limited sample did not lead to retraining of the model due to the correct division of data into test, training and control batches and the use of the quasi-Newton optimization method. The model has displayed a high level accuracy and reliability. Artificial neural networks are capable of identifying nonlinear dependencies between the parameters with no a priori assumptions. Discussion and Conclusion. The suggested model is not a substitute for the existing calculations, but it serves as an efficient digital tool for quick verification of design solutions, optimization of reinforcement and improvement of structural reliability. Its implementation into BIM systems and digital construction platforms is in compliance with the requirements of Industry 4.0 and creates new opportunities for designing prefabricated reinforced concrete structures.

The paper presents the results of developing paint and varnish coatings for protecting metal bridge structures, featuring high durability under operating conditions. The focus is on preparing metal surfaces for painting, specifically developing a formulation for a pre-treatment composition prior to paint and varnish application. The composition is a solution based on mixed solvents, one of which is an ester and the other an aromatic hydrocarbon, containing nanomaterials. The specific solvents used in the composition, as well as the types and amounts of nanomaterials, depend on the type of film-forming agent in the applied paint and varnish. The conducted studies on a specific example of a composition formulation, including a solution based on mixed solvents (butyl acetate (52-55 wt.%) and toluene (45-48 wt.%), containing a concentrate with carbon nanotubes and silicon dioxide, in an amount of 0.01-0.2 wt.%, including 10 wt.% single-wall carbon nanotubes and silicon dioxide nanoparticles and 90 wt.% mixture of triethylene glycol dimethacrylate and alkylammonium salt of high-molecular copolymers showed that acrylic paint and varnish coatings acquire increased physical and mechanical properties (adhesive strength, abrasion resistance, resistance to deformation effects, etc.). At the same time, there is an increase in the dielectric constant of the coating (from 16.45 to 18.39), which characterizes its increased conductivity, as well as a decrease in the dielectric loss tangent (from 0.017 to 0.008), which indicates the production of antistatic coatings. The chemical resistance of the coatings increases, which characterizes their resistance to aggressive environments, expressed in better preservation of properties according to the criteria: change in gloss (hue), whitening, blistering, peeling, wrinkling. When considering the formation of interaction on the metal surface during its contact with the coating during surface treatment with nanomaterials, the following mechanisms of action of nanomaterials with a metal surface were revealed, which are consistent with the provisions of the electrical theory of adhesion and the theory of the physical chemistry of polymers: interaction of nanomaterials with surface atoms of the metal with the formation of electrovalent interaction by the donor-acceptor mechanism; Chemical interaction (chemisorption) of the active sites on the surface of carbon nanotubes with the metal surface layer. Industrial testing of the resulting solution yielded a positive result: after 28 months of operation, the coating obtained by surface treatment with the nanomaterial composition, compared to the untreated coating, performs its functions and exhibits superior decorative and protective properties. The technical and economic efficiency of the developed approach is ensured by improved adhesive-cohesive interaction of paint and varnish coatings, which creates conditions for extending their service life and periods between repairs; and by reducing resource and energy costs without compromising coating quality due to the use of a small amount of binary nanomaterials in the developed composition.

This research is determined by growing interest in the cultural and architectural heritage of the Turkic peoples, whose traditional housing results from centuries of adaptation to diverse natural and climatic conditions. Purpose: The aim of the work is to analyze the evolution of the architectural forms of the Turkic peoples, reflecting the synthesis of nomadic and sedentary traditions. Methodology/approach: A comparative analysis of spatial planning and visual-spatial solutions, geographical and climatic analysis, and analysis of cultural traditions reflected in ornamentation, zoning, and building materials. Spatial planning and visualization of traditional and modern housing of Turkic peoples depend on natural and climatic conditions and cultural traditions. The analysis is given to the main types of traditional houses, such as yurts, log and adobe houses, are analyzed, and their structure, function, and decoration reflect social values and adaptation to the landscape. Research findings: Spatial planning solutions closely relate to the climate: mobile yurts prevail in steppes, log and stone houses in the mountains, and log and adobe dwellings in the forest steppe. Modern houses in Turkic regions preserve elements of traditional architecture such as zoning, ornamentation, eastward orientation, and the use of natural materials. Research implications: The identified principles can be used to design modern residential houses with ethnocultural identity. Value: It is shown that the architectural continuity of the Turkic peoples is manifested in the preservation of sacred geometry, ornamentation, principles of internal zoning, and climatic adaptation.