The article proposes to strengthen the upper chord of the triangular spacer system with fiberglass. The material used for strengthening shows high efficiency in increasing the strength of the wooden element for the 1st group of limit states. The material proposed for strengthening does not lead to a change in the original decorative expressiveness of wooden structures, and maintains the service life.

Keywords: spacer structure, upper chord, glued laminated board element, modulus of elasticity, volumetric weight, geometric characteristics, bending moment, longitudinal compressive force, structural reinforcement, composite material

Numerical studies of the temperature and humidity properties of three types of enclosing exterior walls have been performed using gas-silicate autoclave hardening blocks as the base, and a comparative analysis of the results of the study with the results of research by other authors has been carried out. The design features affecting the condensation of moisture in multilayer walls are revealed. It has been found that multilayer walls have a number of disadvantages that affect their performance and durability, in particular, the presence of materials with different vapor permeability and moisture absorption, which leads to the accumulation of moisture inside the wall. The prospects of using single-layer structures and the importance of choosing the right material for the finishing layer are shown. An example of the use of a finishing material based on acrylic and marble chips is given, and the need for further research of this material is shown.

Keywords: gas silicate block, condensation zone, plaster facade, finishing material, acrylic, marble chips

In the practice of hydraulic engineering construction, especially in mountainous and foothill areas, quite often there are conditions under which it is economically advantageous to build a dam reservoir from heterogeneous local materials with different filtration characteristics. As a rule, in such areas near the site of the future dam there is not enough homogeneous construction soil that meets all the requirements. However, it is possible to find soils that differ in water permeability, but in sufficient quantity for the construction of the body of this dam.

Keywords: reservoir, dam, filtration, soil, section, pool, anti-seepage core, flow, slope

The effectiveness of advanced pavement defect detection algorithms is considered depending on the data collection devices used, such as cameras, GPR, LiDAR and IMU sensors installed in smartphones. Rational use of these hardware and software tools will allow utilities to identify and eliminate road surface defects in a timely manner, thereby improving road safety.

Keywords: transportation sector, pavement defects, mobile road laboratories, neural network algorithms, computer vision

The problem of concrete strength control when using permanent formwork is considered. The results of the analysis of the experience of using the dependences of concrete strength on temperature-time parameters for forecasting and assessing the strength of concrete during its hardening, including the limits of application of the proposed dependencies, are presented. It is established that the methods of assessing the strength of concrete in a structure by its maturity allow for effective control of the strength of concrete structures concreted in permanent formwork, when there is no access to the concrete surface for non-destructive testing. Recommendations are given on the use of temperature-time dependencies for predicting concrete strength and the equipment used to implement the method, presented on the Russian market.

Keywords: non-destructive methods of testing concrete strength, temperature-time parameters, strength prediction, maturity

Intensive wear of the road surface under the influence of traffic loads, climatic factors and structural features of bridges has increased the number of studies in this area. One of the promising areas for improving the operational reliability of bridge structures is filling asphalt concrete mixtures with activated rubber chips, which are highly resistant to wear and mechanical damage. Both traditional paving technologies using polymer-composite mixtures and modern technologies using asphalt concrete filled with activated rubber chips are considered. The advantages of using recycled rubber, which increases the traction properties, wear resistance and durability of the road surface, are considered. A comparative calculation of the cost of pavement reconstruction using the compared technologies was carried out, which showed a significant reduction in the cost of materials and laying asphalt concrete with activated rubber filler compared with polymer composite coatings.

Keywords: activated rubber chips, asphalt concrete, reconstruction of overpasses, road surfaces, wear resistance, traction properties, economic analysis, polymer composite coatings, technological process, recycled materials

The article analyzes modern approaches to the use of innovative materials to create an inclusive environment in residential buildings. The paper examines the main problems associated with the obsolescence of building materials, and offers promising solutions based on the use of adaptive and environmentally friendly technologies that enhance accessibility and comfort.

Keywords: inclusive environment, the problem of outdated materials, innovative materials, innovations, trends and prospects, bioplastics, carbon concrete, OLED panels, adaptive structures, accessibility, comfortable environment, design

The article considers the strengthening of the upper chord of the triangular strut system as a method for restoring the bearing capacity of a glued laminated timber element according to the 1st group of limit states. The strengthening allowed us to obtain as a result of calculations a strength utilization factor not exceeding the limit value.

Keywords: triangular spacer system, upper chord, glued laminated timber element, modulus of elasticity, volumetric weight, compressive force, bending moment

The article discusses the use of carbon anchor harnesses to strengthen building structures. Their design features, installation technologies, and key advantages, including low weight, high strength, corrosion resistance, and durability, are described. An overview of existing experiments demonstrating the reliability of anchor harnesses under load, their effectiveness in preventing the stratification of external reinforcement elements and increasing the strength of joints is given. The shortcomings of the regulatory framework and the lack of practical recommendations on the selection and design of anchor harnesses are indicated. The authors emphasize the need for further research to optimize the interaction of the elements of the reinforced structure-external reinforcement-anchor system.

Keywords: anchor harness, carbon fiber, load-bearing capacity, structural reinforcement, teamwork

Determining the deformability of the bearing structures of the coating, as an indicator of the use of the stiffness of the cross-section of the elements, is an urgent task, which is aimed at solving the current work. The purpose of the article is a comparative calculation of frame structures under the assumption of a different coating truss solution. The following types of load-bearing roof trusses should be considered: segment truss, trapezoidal truss, triangular truss. The calculation of frames using wood as load-bearing structures for the total effect of permanent and short-term loads causing maximum vertical deformations is given. In this paper, the coefficients of using the rigidity of truss structures using wood are determined and the dependence of the stiffness value on the type of outline of the coating truss is established. A comparison of the calculation results with the normative maximum permissible values allowed us to establish the most effective type of outline of the wooden roof truss.

Keywords: coating truss, modulus of elasticity, stiffness, upper belt, slant, lower belt, computational study, through-hole construction, segmental truss

The modern building material, slurry infiltrated fiber concrete - SIFCON, has not only high compressive and tensile strength, but also flexibility and ductility. These properties allow it to be used in nodes of building structures that perceive dynamic, shock, explosive loads, friction, as well as in the area of penetration of reinforced concrete slabs by columns. The paper describes experimental studies of the mechanical properties of samples from ordinary concrete and SIFCON. A comparison of the test results showed the superiority of SIFCON strength indicators over ordinary concrete by 2-4 times. For a wide range of specialists and students in the field of construction design, production of building materials.

Keywords: slurry infiltrated fiber concrete, steel fibers, cement mortar, flexibility, plasticity, energy absorption, water-cement ratio, superplasticizer, compressive strength, bending strength, splitting strength

The use of methods for strengthening soils with Portland cement makes it possible to increase the physical and mechanical properties of soils: strength, frost resistance, water permeability, etc. A technical understanding of the processes of structure formation in reinforced soils makes it possible to regulate the final properties and quality of the layers of highways. To describe the processes of structure formation, it is possible to use the theory of contact interactions and the theory of DLFO. The final properties of the reinforced soil are influenced by the following factors: mineralogy and specific surface area of the soil, water content, amount of cement, curing time and method of compaction.

Keywords: stabilized soils, structure formation of stabilized soils, stabilization with Portland cement, properties of stabilized soils

The aim of this study was to determine the effect of finely ground filler on the properties of slag-alkali binder based on blast furnace slag. An aqueous solution of sodium silicate and caustic soda (aqueous solution of NaOH) was used as a hardening activator with an alkali modulus (weight ratio SiO2/Na2O) equal to 1.0 and 0.5. The results showed that the introduction of Reftinskaya GRES fly ash into the binder instead of ground blast furnace granulated slag causes an increase in the initial setting time, but does not affect the final setting time. No cracking was detected during hardening in mixtures containing fly ash, provided that a complex based on sodium silicate and an aqueous solution of NaOH was used as a hardening activator. The introduction of alkali into the sodium silicate solution helps to reduce the silicate modulus (the mass ratio of SiO2/Na2O) and reduce the formation of shrinkage microcracks due to the formation of a homogeneous structure and the formation of fly ash and the formation of sodium hydroaluminosilicate (H-A-S-N).

Keywords: cement paste, ground granulated slag, fly ash, hardening activator, setting time, shrinkage, microcracks

The article shows calculation on the arrangement of the embankment and the design of reinforced concrete casings on metal staves for stairs. The dam boundaries are located on the territory of a residential complex with a large difference in height. The ground base is prosaic. Calculation of transfer of the soil from II type of drilling to I type by tamping method, which will ensure the strength and reliability of the body of the fill. Constructive actions to ensure resilience are described. The metal piles with forced connecting link and reinforced concrete coaxes in the form of a beam system have been designed.

Keywords: a mound, drilling ground, improvement, dense urban development, sediment, density of the ground, collapse prism, sliding radius, the method of ramming, sling

The use of ash and slag mixtures of thermal power plants in the structures of road coverings of highways makes it possible to significantly increase the volume of their reuse. One of the promising directions is their application in the compositions of stabilized soils. To assess the effectiveness of the use of these materials, such indicators as the cost of construction and the total thickness of the pavement structure are used. According to the results of the conducted research, it was found that the reduction in the total thickness of road clothing with layers of ash and slag mixtures of CHP compared with layers of traditional materials was up to 48%, the reduction in the cost of building road clothing structures using ash and slag mixtures is up to 21%.

Keywords: stabilized soils, ash and slag mixtures, road clothing, base of road clothing

The current problems of the construction industry are considered and an algorithm for the introduction of modern, flexible management methodologies to improve the efficiency of the management process in construction design organizations is proposed, as well as a variant of an integrated efficiency assessment system taking into account KPIs is being developed.

Keywords: construction, design organizations, KPIs, flexible management, Agile, Lean manufacturing, stakeholders, efficiency

The paper presents the methodology and results of experimental studies of concrete strength under uniaxial and biaxial compression under dynamic impact. The research results are presented in the form of illustrative tables and graphs. The effect of loading rate and the second principal stress on concrete strength is assessed. Ways for further research development are proposed. The studies have shown that under both static and dynamic loading, the type of stress state and the stress level σ2 significantly affect the strength of concrete. The most noticeable increase in strength occurs during the transition from uniaxial compression to biaxial, even with a small value of the second principal stress σ2. With an increase in the level of lateral compression from 0.2Rb to 0.6Rb, the strength of concrete also increases. Thus, the increase in strength at σ2 = 0.6Rb both under statics and dynamics is more than 40% compared to the strength in uniaxial tests with the corresponding loading rate. The type of stress state and the level of lateral compression affect the dynamic hardening coefficient, but to a lesser extent than the loading rate. A slight increase in k_(b,v) (σ_2) compared to kb,v was observed under biaxial compression with a lateral compression level of 0.4Rb and 0.6Rb.

Keywords: concrete, strength, strength criterion, experimental study, uniaxial compression, biaxial compression, dynamic loading, dynamic hardening coefficient

The article discusses the parametric dependencies of cylindrical rod shells in terms of their effect on the state of force and movement of nodes in the grid area. Critical condition factors are analyzed, taking into account the degree of cell filling and the magnitude of the discrepancy between the specified characteristics. The analysis of the formative parameters is carried out and the rational limits of their possible use are established. The factor of taking into account the size of the cell with the location of the rods inside the faces has been introduced. The basic ratios are obtained and the degree of sensitivity of the calculated models to changes in geometric shape is estimated. The limiting angle of the outlined circle has been found, beyond which the operation of the structure is impossible. The level of dangerous increase in the total parameter along the arc at the lowest possible height of the structure has been determined.

Keywords: cylindrical rod shells, mesh area, degree of cell filling, parametric dependencies, force state, stiffness

The article provides a review and systematisation of works devoted to the application of machine learning for solving problems of research, calculation and design of reinforced concrete structures. It considers the aspects, which are relevant today, related to calculation, design, as well as assessment of the technical condition of objects with the help of various approaches that implement machine learning schemes, including deep learning, ensemble algorithms. It is shown that nowadays in the world construction science this area is rapidly developing and improving. Thus machine learning algorithms solve problems of prediction of design parameters, problems of identification of these or those parameters, defects, damages on the basis of classification algorithms and others. The materials presented in the article will allow specialists to choose the subject area of research more precisely and determine the directions of adaptation and improvement of their own developments in the field of machine learning.

Keywords: machine learning, reinforced concrete structures, regression equations, identification, approximation, artificial intelligence

The article considers the causes of the formation of defects to be evaluated. The methods of obtaining information about the condition of metal corrugated pipes are presented. The main defects arising during the operation of metal corrugated pipes are shown. The most effective methods of assessing the condition of metal corrugated pipes have been determined.

Keywords: corrugated metal pipes, wear, durability, defects, factors, evaluation

We continue to study the stress-strain state of reinforced concrete bonded and unbonded prestressed beams. In this article, we consider the process of crack formation in such structures, relying on the results of testing experimental reinforced concrete samples of bonded and unbonded prestressed beams, as well as their three-dimensional models created in the Abaqus software complex. The results of calculating prototypes according to current standards are compared with experimental data and calculation of a finite element beam model in the Abaqus complex software complex, on the basis of which recommendations are proposed for calculating the crack resistance of prestressed reinforced concrete bonded and unbonded structures. In the course of the analysis, the following conclusions were made: 1) The real crack resistance exceeds the theoretical and obtained during testing of finite element models. When the effect of reinforcement is taken into account, the discrepancy is considerably reduced, so it should be included in the calculation for a more accurate determination of crack resistance. 2. Unbonded prestressed structures have lower crack resistance compared to classical bonded reinforcement.

Keywords: reinforced concrete beams,prestressed structures, bond, rainforcement, crack resistance

Technical solutions aimed at preventing and eliminating the consequences of emergency situations in tunnel construction practice (in terms of laying utility lines or subways) are defined. Technical solutions are given taking into account their implementation in the conditions of structures under construction and in operation, characterized by a repeatable and predictable nature of occurrence.

Keywords: building structures, technology, repair work, underground utilities, tunnel, metro construction

The features of the calculation of nodal joints of frame buildings made of cold-formed steel profiles are considered. The connection of elements of frame buildings made of cold-formed steel profiles for the perception of acting forces is made on bolts using low-carbon steel shapes, the profiles themselves are made of thin-sheet galvanized rolled products. But there are no requirements for the thickness of the shapes and specific thickness values depending on the applied forces in the regulatory documentation, since these compounds are poorly studied in Russia. The calculation of frame buildings made of cold-bent steel profiles and the analysis of nodes with bolted connections was carried out and a method for determining the number of bolts in nodes in two design cases depending on the thickness of the shape was proposed, the need to introduce these requirements into the regulatory documentation for thin-walled structures was shown.

Keywords: cold-formed profile, hot-dip zinc-coated steel sheet, frame building, node, single-bolt connection, shape, crumple, truss, thin-walled structures

The article considers the prospects for the development of modular construction of buildings and structures in the North Caucasus, analyzes the stages of formation and development of this direction in the light of modern trends. Modular technology in construction is a modern method that involves assembling buildings from prefabricated modules. This approach can significantly reduce the time of construction of buildings, improve their quality and reduce costs. In the conditions of the Stavropol Territory, where there is an increase in the population and the need for housing, such technologies can play a key role in solving the problem of providing citizens with comfortable and affordable housing. This article considers the possibilities of using modular technology in house building. The advantages of this technology are considered in terms of quality, savings, time and environmental friendliness, as well as the flexibility of designs and safety both in the production process and during installation at the construction site. The disadvantages of modular construction are also mentioned, such as the complexity of transporting modules, the need for coordination between production and construction, as well as the high cost of production and standardization. The North Caucasus has unique natural and climatic conditions, which opens up opportunities for the use of modular technologies. Modular housing construction is a fairly efficient construction technology that leads to a reduction in waste and ensures greater precision in the manufacture of components.

Keywords: modular technology in construction, construction production, construction technologies, architecture, environment, module, frame buildings, ergonomics, volumetric modular design, modular construction

The study is devoted to improving the methodology of calculation of structures for the impact of explosive loads, including aerial shock waves in UAV attacks. Modern modeling methods are analyzed, a calculation algorithm using non-linear dynamic approaches is proposed. It is shown that the use of spherical discrete elements allows a more accurate assessment of debris destruction and formation. The calculations presented confirm the effectiveness of the proposed approach.

Keywords: Explosive loads, air shock wave, unmanned aerial vehicles, dynamic calculation, destruction of structures, simulation of explosive effects, application of spherical discrete elements, calculation algorithm, formation of debris, non-linear methods