Одеська державна академія будівництва та архітектури
IMPROVING THE ENERGY EFFICIENCY OF RESIDENTIAL BUILDINGS BY MECHANIZED APPLICATION OF THERMAL INSULATION PLASTER USING PLASTERING MACHINES
The article discusses current issues of energy conservation in residential buildings in Ukraine in the context of rising energy costs and the need to improve the energy efficiency of the building stock. Particular attention is paid to heat loss through boarding constructions, which is one of the main causes of energy overconsumption and reduced thermal comfort in residential buildings. The main factors affecting the effectiveness of thermal insulation are analyzed, in particular outdated regulatory requirements, low quality of building materials, errors during the installation of thermal insulation systems, as well as the negative impact of operating conditions on the environment. The paper reviews current domestic and foreign research in the field of energy conservation and thermal insulation of buildings, which made it possible to identify key issues and problematic aspects of the implementation of energy-efficient solutions. An analysis of current regulatory documents, in particular DBN V.2.6-31:2021, and a comparison with previous editions are provided, which indicates a gradual convergence of Ukrainian standards with European requirements. The main types of thermal insulation materials used in modern construction are considered, along with their advantages and disadvantages, taking into account indicators of thermal conductivity, vapor permeability, moisture resistance, fire safety, and environmental friendliness. The prospects for the use of thermal insulation plasters as an effective auxiliary method of reducing heat loss, particularly in the context of building reconstruction and restoration, are examined separately. A comparative characteristic of manual and mechanized methods of applying thermal insulation mixtures using plastering stations is given, their technical and economic advantages and the feasibility of their use depending on the volume and determination of work conditions. It is concluded that the comprehensive implementation of energy efficiency measures in compliance with regulatory requirements, the correct choice of materials and modern installation technologies can reduce heat loss by 40-60%, increase the energy efficiency of residential buildings and ensure comfortable living conditions.
Technology and organization of construction production
Copyright (c) 2026 MODERN CONSTRUCTION AND ARCHITECTURE https://creativecommons.org/licenses/by/4.0
MODERN CONSTRUCTION MANAGEMENT MECHANISMS IN THE POST-WAR RECONSTRUCTION OF UKRAINE
The article examines modern construction mechanisms in the post-war recovery of Ukraine. It i emphasized that as a result of prolonged hostilities, the country has suffered significant human and material losses, while infrastructure, housing, industrial facilities, transport and engineering communications have been destroyed or severely damaged. Under such conditions, the construction sector must become a key industry capable not only of rebuilding destroyed assets but also of modernizing the economy in accordance with global standards. The study highlights the urgent need to establish new organizational structures and management mechanisms in the field of capital construction. Innovative approaches to strategic, multi-project and project management are proposed, including the application of PMBoK:2021 standards, the establishment of professional project management offices (offices PMO), the integration of international experience and the mobilization of investment resources. The research outlines the necessity of a multi-level planning and management system that operates at national, regional and local levels. The key principles and prerequisites for creating an effective mechanism ensuring synchronization among state authorities, business entities and international partners are identified. It is stressed that the construction complex can serve as a locomotive of economic growth, contribute to the balanced development of regions, improve living standards and accelerate Ukraine’s integration into the global community. As world practice shows, the application of the developed progress management mechanism in Ukraine, compared to traditional forms of program and project management, will allow: to reduce labor costs and the duration of the development and implementation of program and project activities by 10...18%, and their cost by 9...17% and more. The results of the study have practical value for shaping new models of project management in recovery initiatives and provide a foundation for further scientific exploration of post-war reconstruction processes.
INTEGRATION OF COAGULATION-AEROBIC TECHNOLOGY INTO THE RECONSTRUCTION OF WASTEWATER TREATMENT PLANTS: ENGINEERING CALCULATIONS AND TECHNOLOGICAL RECOMMENDATIONS
The article considers the possibility of improving the efficiency of wastewater sludge treatment by integrating coagulation-aerobic technology into existing aerobic mineralizers at sewage treatment plants. The relevance of the study is determined by the need to modernize outdated wastewater treatment plants designed in the 1970s–1990s, which exhibit low sludge thickening efficiency. The work aims to justify the design and technological solutions for the reconstruction of aerobic stabilizers by introducing a coagulant dosing unit and a reaction-mixing zone, thereby intensifying the processes of gravitational compaction and aerobic stabilization of sludge. The kinetics of gravitational compaction using aluminum-containing coagulants of the "OPTIPAC" type at a dose of 1% of the suspension volume were studied, and aerobic stabilization was carried out for 6 days. Based on the experimental dependencies obtained, engineering calculations of the aerobic stabilizer parameters for a wastewater treatment plant with a capacity of 10,000 m³/day were performed. The required stabilization volume, aeration parameters, reagent consumption, and dosing unit design characteristics were determined. It was shown that the actual volume of existing mineralizers significantly exceeds the calculated requirement, allowing the organization of additional technological zones without the construction of new facilities. The proposed technological scheme provides for the sequential implementation of coagulation, gravitational compaction, and aerobic stabilization of sludge within a single tank. The results of the study show that reagent treatment increases particle settling rate, reduces sludge moisture content, and reduces sludge volume. The results obtained can be used to reconstruct existing wastewater treatment plants in small and medium-sized settlements. They will help improve the energy efficiency and environmental safety of wastewater systems.
AN ANALYSIS OF THE REGULATORY FRAMEWORK GOVERNING THE ENERGY EFFICIENCY OF THE BUILDING ENVELOPE OF RESIDENTIAL BUILDINGS OF THE SOVIET AND POST-SOVIET PERIODS IN UKRAINE
The need to analyze the regulatory framework governing the energy efficiency of the building envelope of residential premises is associated with the existence of a significant number of dwellings built during the Soviet era in Ukraine, which currently makes up the lion's share of the entire existing housing stock. The high pace of mass construction at that time was achieved through the speed of assembly work, the simplicity of the materials, and the unpretentious nature of the structures; consequently, energy efficiency was never a priority. Upon Ukraine's independence and the transition from a planned economy to a market economy, energy tariffs began to increase, which led to the need to build according to different standards. Beginning in 1994, a new regulatory framework of independent Ukraine began to take shape, starting with legislative acts. This, in turn, resulted in the creation of relevant government agencies and new energy-saving requirements, which began to be implemented in the construction sector. And while modern regulatory requirements for energy efficiency in new construction take into account the need to save energy, such requirements are not practically available in the Soviet regulatory framework, as its analysis has shown. This key factor must be taken into account in future studies of the condition of residential buildings. Consequently, the housing stock built since Ukraine gained independence differs significantly from the Soviet-era stock in terms of energy saving. Studying, understanding, and addressing the issue of low energy efficiency in the obsolete housing stock will enable a rational approach to the implementation of thermal modernization, taking into account modern construction materials and construction technologies. After all, carrying out thermal modernization work on existing housing on a nationwide scale will allow, firstly, a significant reduction in the load on energy networks and, secondly, a significant reduction in energy consumption and heating and air conditioning costs. The long period of Soviet-era construction left behind hundreds of millions of square meters of housing stock that is both structurally and physically dilapidated. It constitutes a significant part and requires major thermal retrofitting and the costs associated with implementing this project. Part of the Soviet-era housing stock has already reached the standard depreciation period, and the question of whether it remains feasible to continue operating these buildings and whether they can be modernized remains a pressing issue. In addressing this issue, attention should be paid both to the existing experience of implementing thermal modernization solutions by Ukrainian associations of co-owners of multi-apartment buildings and to the experience of the countries of the former Warsaw Pact.
THE INFLUENCE OF THE GEOMETRIC SHAPE OF THE PRODUCT ON THE FORMATION AND ADAPTATION OF THE MESH OF INTERNAL DISTRIBUTION SURFACES
The article analyses the influence of product geometry on adaptation processes occurring during the formation of the structure of building composite materials at various stages of their manufacture and operation. It is shown that the geometric parameters of the product not only determine the spatial boundaries of the material, but also form its outer surface as an independent structural element that actively participates in the processes of structure formation. It is through the interaction of the outer surface with the volume of the material that the redistribution of thermal, mechanical and deformation influences is realised, which determines the specifics of the distribution of stresses and deformations in the product, and also influences the formation and development of internal distribution surfaces. It is demonstrated that changes in product geometry significantly alter stress localization, the intensity of deformation processes, and the nature of microcrack formation. Active structural elements, including internal separation surfaces, pores, and microcracks, are considered key components of adaptive mechanisms, as they ensure stress redistribution and enhance the material’s ability to adapt to external influences without loss of integrity. To investigate these processes, a graphical-analytical method is applied, enabling clear visualization of deformation distribution and identification of stress concentration zones. In addition, image analysis methods and evaluation of the damage coefficient are used to provide a quantitative assessment of the level of structural changes and the adaptive capacity of the composite material. In conclusion, it is established that product geometry, together with technological formation parameters, significantly determines the material structure and its performance characteristics, including strength, crack resistance, and durability. Moreover, the obtained results can be used in the design of building products with complex shapes to predict their behavior under operational loads. Consideration of geometric factors makes it possible to optimize the composition and structure of composite materials, increase their reliability, reduce damage levels, and ensure more efficient use of material resources in the construction industry. This opens prospects for further research and the implementation of adaptive materials in modern construction and engineering structures.
ASSESSMENT OF DURABILITY AND COMPLIANCE WITH THE NORMATIVE SERVICE LIFE OF REINFORCED CONCRETE STRUCTURES UNDER CLIMATIC CONDITIONS OF UKRAINE
A significant share of Ukraine's prefabricated reinforced concrete building stock, constructed in the 1960s–1990s, is currently in service beyond its designed service life. The concrete cover in such structures often does not exceed 15-20 mm, which, combined with rising CO₂ concentrations in urban atmospheres and seasonal climatic effects, substantially accelerates concrete carbonation and reinforcement corrosion, reducing structural load capacity and durability. This paper develops and validates a methodology for assessing the compliance of reinforced concrete structures with normative service life requirements for five representative Ukrainian cities: Chernihiv, Kyiv, Lviv, Kharkiv and Dnipro. The methodology is based on analytical carbonation and corrosion models and determines the critical time ‒ the moment at which reinforcement degradation reaches a threshold level beyond which structural load capacity falls below an acceptable limit. The results were compared with the normative service life requirements of DBN V.1.2-14:2018 for residential and public buildings. It was found that at a concrete cover of 20 mm, none of the studied regions meets the 100-year normative service life for residential buildings: the critical time ranges from 52 to 76 years, i.e. 24-48 years short of the normative requirement. For industrial buildings (60 years), the requirements are not met in Dnipro and Kyiv. Sensitivity analysis showed that increasing the concrete cover to 30 mm allows Chernihiv and Lviv to achieve the 100-year service life, while Dnipro, Kharkiv and Kyiv require additional protective measures. The results confirm previous research conclusions on the need for rehabilitation of Ukraine's reinforced concrete building stock and provide quantitative justification for regionally differentiated requirements for concrete cover and concrete class in the design of new structures.
ON THE ISSUE OF CHOOSING THE FORM OF THE BASIC ELEMENT OF SPATIAL STRUCTURAL COVERING
Spatial steel structural roof systems are load-bearing structures widely used to cover large spans in buildings of various functional purposes. Previous studies indicate that the spatial behavior of such systems ensures efficient interaction of bar members, leading to internal force redistribution and enabling a reduction in structural cost through rational selection of the structural configuration. However, the performance of planar and curved steel spatial roof systems is governed by individual parameters while other system characteristics remain unchanged. One of the key parameters affecting the stress–strain state is the support condition of the slab component, particularly the number of supports and their layout in plan. Columns may be concentrated in corner zones, arranged along the external perimeter, located along the longitudinal sides, or introduced within the internal slab area. Another significant parameter is the geometric configuration of the spatial basic module of the steel structural roof, which is periodically repeated in two orthogonal directions and defines the overall structural system. The spatial basic module consists of vertical, inclined, and horizontal members assembled into an ordered three-dimensional framework. The resemblance of this configuration to naturally occurring crystal lattices results in increased structural stiffness and enhanced load-bearing performance under applied loads. In this study, a numerical investigation of three variants of spatial steel structures was performed using the finite element method. The computational models differed only in the configuration of the spatial basic module, whereas the slab geometry, material properties, mechanical characteristics of the members, applied loads and boundary conditions were kept constant. For each variant, the stress–strain state was evaluated, stability parameters were assessed, and member cross-sections were designed in accordance with current design codes. The most rational structural solution was identified based on a material efficiency criterion by calculating the total structural weight. The model based on the type 3 spatial basic module exhibited the highest material efficiency, with a total weight reduction of 34.2% compared to the first variant and 21% compared to the second.
ANALYSIS OF THROUGH DAMAGE OF REINFORCED CONCRETE BEAMS IN THE SUPPORT ZONES UNDER LOAD
This paper presents the results of a numerical study of the effect of through opening of various diameters, contents, and spacing on the stress-strain state of reinforced concrete beams in tensioned and inclined areas. The relevance of the topic is determined by modern requirements for the optimization of structures in the construction and reconstruction of buildings, when it is necessary to lay engineering communications through the body of load-bearing elements without losing their reliability and strength. The modeling was performed in the LIRA-CAD environment using a physically nonlinear formulation of the problem. Concrete is modeled using spatial volumetric elements of the KE 236 type, taking into account the 25th exponential deformation law, and reinforcement is modeled using finite elements of the KE 210 type with approximation of the σ–ε diagram by a piecewise linear dependence. This approach allows tracking the change in stress and deformation from the initial elastic stage to the formation and development of cracks in inclined and stretched areas. The results obtained showed that the effect of the openings significantly depends on their geometric parameters and location. Also, holes with a diameter of 20 mm and a pitch of 2d create a local stress concentration in the tensile zone, but do not lead to a significant reduction in the stiffness of the structure. With an increase in diameter to 30 mm and an increase in pitch to 4d, the stress in the concrete decreases by 5–7%, and the area of detected crack opening expands but has a more uniform character. With an increase in the number of holes, there is a tendency for deformations to increase within the range of 3–6%, but the destruction remains plastic. Studies of inclined sections have shown that vertically located damage near the zone of origin of inclined cracks affects the trajectory of their development, but at reasonable distances between holes does not cause a critical reduction in load-bearing capacity. On the contrary, in some combinations (smaller diameter, larger pitch), stress redistribution and a decrease in concentration at the crack tips were observed. Thus, the results of the work confirm that the presence of through holes in the tension and inclined zones of reinforced concrete beams does not always have a negative effect. With a rational choice of diameter, pitch, and number of holes, it is possible to achieve a controlled effect on the working elements, avoiding brittle failure. The results obtained can be used in the design of structures with holes for engineering networks, ensuring safe operation without a significant reduction in load-bearing capacity.
APPLICATION OF DIC METHOD FOR DETERMINING STRESS-STRAIN STATE OF FLEXIBLE REINFORCED CONCRETE SLABS
The article is devoted to the application of the Digital Image Correlation DIC method for experimental determination of the stress-strain state of reinforced concrete slabs. Assessment of the bearing capacity and deformability of reinforced concrete structures is an important task in the design and operation of buildings and structures especially when strengthening existing structures is necessary. Traditional strain measurement methods using strain gauges and deflectometers provide point measurements which do not allow obtaining a complete picture of strain distribution over the entire surface of an element. The aim of the research was experimental determination of the stress-strain state of reinforced concrete slabs using the DIC method to assess their behavior before strengthening. A control specimen of a reinforced concrete slab with dimensions 2000×590×50 mm was manufactured from C30/40 concrete with 6Ø8 A500C reinforcement reinforcement ratio ρ=1.65%. Holes with diameter 110 mm were made in the slab for future beam strengthening. A speckle pattern was applied to the end surface for DIC tracking. The tests were carried out on a UTEST hydraulic press according to a four-point bending scheme with working span L=1900 mm. A stereo DIC system with two digital cameras and Vic-3D software was used to record strains. Data from the DIC system were synchronized with load indicators. Complete load-deflection and load-strain diagrams were obtained. Characteristic points crack formation at P=2.4 kN f=14 mm yielding at P=8.6 kN f=66 mm ε=2.5‰ maximum P=9.81 kN at f=114 mm. Maximum tensile reinforcement straиi ns reached 9.85‰ which is 4 times higher than the yield limit. The DIC method provided visualization of strain fields and accurate recording of crack formation. The research results confirmed the high efficiency of the DIC method for comprehensive assessment of the stress-strain state of reinforced concrete slabs. The obtained experimental data will serve as a basis for comparison with the results of testing strengthened slabs.
INSERT-HOUSES. HISTORICAL ASPECTS OF FORMATION AND FUNDAMENTALS OF DEFINITION
The article is devoted to the study of the possibilities of new construction within the conditions of dense, already established development of central urban blocks without a radical transformation of their structure. The main subject of the research is a detailed examination of the method of infiltrative intervention into the existing historical environment, in particular through the use of infill buildings as one of the key elements of this process. Based on a comprehensive analysis, classification criteria for defining the concept of an infill building have been formulated, the evolution of the formation of this building type has been outlined, and the factors of external influence and the main development trends have been investigated. Special attention in the study is paid to the historical aspect of the formation of cellular block development, since contemporary infill buildings are direct "descendants" of this type of urban fabric. It can even be argued that they are entirely dependent ‒ both physically and "mentally" – on the state of its preservation, effectively functioning as point implants within the existing urban environment. If there were no damaged or lost parcels, there would be no reason to introduce modern infill buildings into the urban fabric in the context considered. Therefore, in the design and realization of such structures, it is very important to understand and correctly apply this "genetic" code of the original source, even despite their completely different stylistic and compositional structure. The application of the latest design and construction methods is also an effective way of modernizing historical urban blocks. The primary goal of creating modern examples of infiltrative architecture should be not only to assist in restoring lost fragments of block development, but also to become objects of attention and admiration in their own right. Under the conditions of contemporary Ukraine, the study and application of methods of point infiltrative construction are a highly important and relevant process in the context of post-war reconstruction, when the country will have to rebuild elements of damaged urban block development lost as a result of enemy shelling. Such experience will be especially valuable for frontline cities of Ukraine (Kharkiv, Sumy, Kherson, Kryvyi Rih, and others), which have suffered the most from the enemy invasion.
APPLICATION OF BUILDING PHYSICS METHODS FOR NATURAL LIGHTING OF UNDERGROUND ROOMS OF EDUCATIONAL INSTITUTIONS
Since the beginning of Russia’s full-scale invasion of Ukraine, the construction of underground public buildings has become a strategic priority for protecting civilians, particularly in frontline regions. For the first time in global practice, fully underground schools and kindergartens have been implemented as facilities capable of mitigating the effects of blast waves, fragmentation, and radiation hazards. However, the absence of natural daylight in such environments creates significant sanitary-hygienic, physiological, and psychological challenges, especially for children who remain underground for extended periods. Insufficient daylight negatively affects circadian rhythms, visual performance, emotional stability, and learning efficiency. The purpose of this study is to develop practical recommendations for the integration of natural daylighting systems into underground educational buildings. The research methodology is based on a systems approach, theoretical analysis, review of international case studies, evaluation of Ukrainian regulatory documents, and examination of modern daylight transportation technologies, including light pipes, fiber-optic systems, heliostats, mirror light guides, and reflective light tunnels. The paper presents a design proposal for an underground kindergarten in which daylight transportation is combined with the ventilation system into a unified engineering unit. Light-collecting elements are placed on separate reinforced concrete columns located outside the debris zone, ensuring system operability in case of structural damage. The design incorporates spherical collectors, reflective light guides with 90° rotation, protective dampers with automatic sealing, and transformer furniture for flexible spatial use. The results demonstrate that transported natural lighting improves visual comfort, supports healthy biological rhythms, reduces dependence on artificial lighting, and enhances the psychological well-being of users in protected underground environments. The scientific novelty lies in the first comprehensive method for providing daylight in underground educational facilities in Ukraine under wartime conditions. The practical significance consists in the applicability of the proposed solutions for the design of protected schools, kindergartens, and hospitals, contributing to energy efficiency, environmental sustainability, and improved quality of life in underground architecture.
THERMAL AND AEROMODELS OF ENERGY EQUIPMENT OF RESIDENTIAL COMPLEXES
During accidents or destruction of the infrastructure of residential complexes at low temperatures, it is necessary to restore the operation of heat supply systems in a short time. It is convenient to use gas tube boilers for this. But we need new solutions to the problems of increasing the power and energy efficiency of equipment and systems due to the reduction of resistances to the movement of liquids or gases, as well as the intensification of heat transfer. Numerous studies have shown that an increase in the heat transfer coefficient at the gas-metal wall interface by 2-5 times leads to an increase in energy consumption of boiler fans by 10 times or more. The article uses three research methods to improve the performance of boilers. Visual diagnostics of the movement of liquids and gases made it possible to identify signs of self-organization of the flow structure. Hydraulic studies in slot channels, where only the height h varied in the range h = 0.2-2.5 mm, confirmed that the distribution structure of the pulsation components of the dynamic part of the energy affects the increase or decrease in speed at a given initial pressure. The thermal experiment showed that the flow structure also affects the nature of the change in the heat transfer coefficient. For channel sizes where the pulsation components have positive values, the increase in the heat transfer coefficient is much more intense than for sizes where the pulsations have negative values. That is, visual studies of the flow structure and the correct choice of transverse channel sizes can solve the problem of increasing the flow up to 24% without additional energy costs, as well as eliminate the problem of uncertainty when solving the problem of intensifying heat transfer at the gas-metal wall boundary. Visual studies of the jet in a flooded space provide information for solving the problem of intensifying heat transfer. The use of turbulators in gas-tube boilers ensured an increase in boiler efficiency from hк.1 = 0.84 to hк.2 = 0.929. At the same time, the energy consumption for fan operation changed slightly. The use of visual diagnostics of the flow structure makes it possible to solve hydraulic and thermal problems when developing or improving energy equipment for housing complexes.
Copyright (c) MODERN CONSTRUCTION AND ARCHITECTURE
DURABILITY OF RIGID PAVEMENT CONCRETE REINFORCED WITH BASALT FIBER
The purpose of the work is the development of fiber-reinforced concrete compositions for rigid pavements with properties of high strength, frost resistance and wear resistance due to the use of polycarboxylate type superplasticizer and dispersed reinforcement. The experiments were conducted according to an optimal 3-factor 15-point plan. The following composition factors were varied: the amount of Portland cement CEM I 42.5 R (from 290 to 350 kg/m3); the amount of basalt fiber BAUCON®-bazalt (from 0.9 to 1.5 kg/m3); the amount of polycarboxylate superplasticizer STACHEMENT 2570/5/G (from 0.6 to 1 % by weight of cement). The workability of all developed mixtures was S1, which corresponded to a cone slump 2...3 cm. Research results shows when increasing the amount of cement and the amount of superplasticizer to 0.9 – 1.0 %, the W/C of the mixtures decreases. The amount of basalt fiber practically does not affect the W/C of the mixture. Due to increase in the amount of Portland cement, the strength of fiber-reinforced concrete is increases, as expected. With an increase in the amount of basalt fiber to 1.3 – 1.4 kg/m3, the tensile strength in bending of concrete increases by 12 – 21 %, while the compressive strength changes insignificantly. Fiber concrete with a superplasticizer content of about 0.9 % has the highest compressive and tensile strength in bending. Moreover, due to increase in the amount of Portland cement from 290 to 350 kg/m3, the frost resistance of concrete increases to about 100 cycles. Due to the increase in strength of that composition, the wear resistance of concrete was increased. With an increase in the amount of basalt fiber from 0.9 to 1.3 – 1.4 kg/m3, the wear resistance of concrete increases by 11 – 16 %, and frost resistance increases to approximately 50 cycles. The change in the amount of superplasticizer has little effect on the wear resistance of concrete. However, with an increase in the amount of additive STACHEMENT 2570/5/G from 0.6 to 0.9 % by weight of cement, the frost resistance of fiber-reinforced concrete increases to about 50 cycles. Fiber concretes with a rational amount of dispersed reinforcement (1.3 – 1.4 kg/m3) and superplasticizer (0.9 %), depending on the amount of cement, have compressive strength from 43 to 60 MPa; tensile strength in bending from 4.9 to 6.4 MPa; wear resistance from 0.31 to 0.37 g/cm2 and frost resistance from F200 to F300. This ensures the high durability of the developed fiber-reinforced concrete for rigid pavements.
Copyright (c) СУЧАСНЕ БУДІВНИЦТВО ТА АРХІТЕКТУРА
PROPERTIES OF CONCRETE AND FIBER-REINFORCED CONCRETE FOR BASES OF ROAD CLOTHES BASED ON SECONDARY AGGREGATES WITH HETEROGENEOUS COMPOSITION
The problem of disposal of concrete scrap of dismantled building structures is relevant for most countries of the world. For Ukraine, this problem is even more acute due to the significant amount of destruction caused by hostilities and rocket attacks. In current research the properties of concrete and fibre-reinforced concrete for the bases of road clothes based on natural and secondary aggregates were compared: granite river gravel, secondary crushed stone with a heterogeneous composition, quartz sand and secondary sand from recycled reinforced concrete structures. CEM III/A slag Portland cement with a blast furnace slag content of 65% and a polycarboxylate type superplasticizer were used. Three series of samples were studied: without fibre; with glass fibre ANTI-CRAK HP 12 (length 12 mm, diameter 0.017 mm, equivalent thread diameter 0.3 mm) in the amount of 1 kg/m3; with polypropylene fibre BeneSteel 55 (length 55 mm, equivalent thread diameter 0.48 mm) in the amount of 4 kg/m3. In each series, concrete on granite gravel and quartz sand, concrete on secondary crushed stone and quartz sand, concrete on secondary crushed stone and secondary sand were studied. The workability of all mixtures was equal to S1. Due to the use of different types of aggregates and fibres, the W/C of concrete mixtures differed significantly. Concretes on secondary aggregates had a higher W/C than on natural aggregates. When using the Anti-Crak HP 12 fibre, the mobility of mixtures with equal W/C increased by 5.5 – 6.9 %. When using BeneSteel 55 fibre, W/C increased by 10.6 – 15.5 %. The type of aggregate had a significant effect on the average density of concrete. When using secondary crushed stone and quartz sand, the average density decreased by 3.8 – 4.6 %. When using secondary crushed stone simultaneously with secondary sand, the average density of concrete decreased by 5.2 – 8.5 %. When using Anti-Crak HP 12 fiber, the average density of concrete decreases by 2 %, when using BeneSteel 55 fibre – up to 4.1 %. Concretes on secondary crushed stone with heterogeneous composition and quartz sand had 4 % higher compressive strength and 2 % higher tensile strength in bending than concretes on granite gravel and similar sand (29.8 MPa and 3.18 MPa, respectively). When secondary crushed stone is used simultaneously with secondary sand, the compressive strength of concrete is only 1.1 % lower than the strength of concrete on natural aggregates, and the tensile strength in bending is 10 % lower. This confirms the possibility of effective use of these concretes for arranging of bases of road clothes. The high-quality performance of secondary aggregates in concrete explains due to their better adhesion to the cement-sand matrix. Dispersed fibre reinforcement with Anti-Crak HP 12 has a positive effect on the compressive strength of concrete on all types of aggregate and increases the tensile strength of concrete on natural aggregates. The use of BeneSteel 55 fibre was not effective due to a significant increase in the W/C of the mixture when it was introduced. In general, taking into account the economic factor, dispersion reinforcement of concrete on secondary aggregates with the types of fibres used in the research is not advisable.
STUDY OF MODIFIED BINDER FOR PRODUCTION OF AERATED CONCRETE
In the case of energy saving, the main direction in the technology of modern wall materials is to reduce the density in order to achieve better thermal performance while simultaneously increasing the strength characteristics, i.e. creation of effective wall materials. One of these materials is aerated concrete, which is successfully used all over the world. One of the ways to increase the physical and mechanical properties of the binder as the main component of aerated concrete and to expand the raw material base can be the use of waste from all kinds of production, as well as the secondary use of damaged building materials from destroyed buildings and structures as a result of hostilities (recycling). The purpose of the research is to obtain aerated concrete on a modified binder using recycling of destroyed building materials. At this stage, a modified binder is being studied. As a result of the research, the optimal ratio of the components of the modified binder (Portland cement, metakaolin, brick mortar) was determined. Mathematical models describing the dependence of the bending and compression strength of the binder on its composition were obtained. The results of X-ray phase and differential thermal analysis show that the introduction of methacoaline and brick mortar additives into the binder based on Portland cement, after 28 days of normal hardening, do not cause new phase and mineralogical formations compared to samples without additives, but only affect the quantitative mineralogical storage. More intensively expressed hydro-silicate phases and a decrease in crystallization calcium hydroxide are observed. The micrographs of the structure of the obtained binder clearly show the monolithic structure of the cement stone, the alkali-dispersed cement grains, sand and calcium hydro-silicate clusters are visible.
BEARING CAPACITY, DEFORMITY AND CRACK RESISTANCE OF DAMAGED BEAMS REINFORCED WITH FIBER CONCRETE
The results of experimental studies of the load-bearing capacity, deformability and crack resistance of damaged beams reinforced with fiber concrete in the compressed and stretched zone are presented. Test samples are made of concrete and fiber concrete. The amount of steel fiber in fiber concrete is 2% of the volume of the product. Preliminary tests were carried out on prisms and cubes. During the manufacture of beam samples, before concreting, a foam insert was installed in the area of planned damage, the shape and dimensions of which corresponded to the damage. After the concrete set to 70% grade strength, the liner was pulled out, and the resulting cavity was filled with a 2% mixture of fiber concrete. Tests of material samples showed that the introduction of steel fiber into the composition of concrete in the amount of 2% by volume increases the compressive strength limit by 15.3%. The initial modulus of elasticity of fiber concrete of the specified mixture is 38.0% higher than that of ordinary concrete of this composition. Conducted experimental studies of damaged beams showed that a beam whose cross-section is 40% damaged in the middle-compressed zone, and the shape of the damage is close to rectangular, has a load-bearing capacity of 92.0 kN, or 93.9% of the load-bearing capacity of an undamaged beam. Cracking started at the 4th loading stage, when the load value was 26.0kN, i.e. 28.3% of the bearing capacity of the damaged beam. The maximum final crack opening width was 0.6 mm. A beam whose section is 40% damaged in the mid-stretch zone has a load-bearing capacity of 92.4 kN, or 93.2% of the load-bearing capacity of an undamaged beam. Cracking started at the 5th loading stage, when the load was 32.5kN, i.e. 35.2% of the bearing capacity of the damaged beam. The maximum final crack opening width was 0.8 mm. It is claimed that the strengthening of a beam with 40% damage in the compressed or stretched zone in the manner considered in the paper is effective, as it allows achieving its load-bearing capacity, which is more than 93% of the load-bearing capacity of an undamaged beam.
MODELING OF STRESS-STRAIN STATE AND STRENGTH OF DAMAGED CONCRETE BEAMS REINFORCED WITH CARBON FIBER FABRIC IN PC "LIRA-SAPR"
The study examines the problem of preserving and improving the architectural heritage in Ukraine. Many buildings and structures have a long service life or are already deteriorating due to their age and other factors. This is particularly true for reinforced concrete structures, which often have various defects and damage. Unfortunately, there are no clear methods for assessing the residual load-bearing capacity of such structures. However, the research indicates that the residual potential of damaged elements may be significantly underestimated. Therefore, it is crucial to explore and apply effective innovative solutions for strengthening these constructions. One such solution involves using composite materials (fiber-reinforced polymers, FRP) for external reinforcement of structures. Composite materials offer numerous advantages, including high strength, low weight, resistance to aggressive environments, and durability. The article presents the results of a numerical experiment aimed at investigating the influence of damage and reinforcement with carbon fiber-reinforced polymer (CFRP) on the stress-strain state and residual load-bearing capacity of concrete beams with basalt-plastic reinforcement (BFRP). For the experiment, 15 rectangular beams with dimensions of 2000×200×100 mm were prepared and nonlinearly analyzed using the "LIRA-SAPR" software, which employs the finite element method. The data obtained for each beam were compared with the results of laboratory tests, revealing that CFRP reinforcement increases the residual load-bearing capacity of the beams without significantly affecting their working deformation. Additionally, a comparative analysis was conducted on the residual load-bearing capacity and stress-strain state of the beam components: CFRP fabric, concrete, and reinforcement. The authors assert that modeling the complex stress-strain state of experimental basalt-concrete beams using nonlinear finite element calculations through the "LIRA-SAPR" software accurately reproduces experimental results, provides insight into the most likely failure mode, and reliably predicts their load-bearing capacity.
PROSPECTIVE DIRECTIONS OF URBAN CONCEPTS TRANSFORMATION IN THE CONTEXT OF THE IMMERSIVE PRESENCE ENVIRONMENTS DEVELOPMENT
The proliferation of immersive presence environments (an artificially created multimedia environment of an alternative reality) is evolving into a widespread social phenomenon that gradually influences how people live and interact. As a result, it has the potential to reshape expectations and demands regarding living spaces and their arrangement. While numerous studies have explored the impact of virtual and augmented reality technologies on urban planning, relatively little attention has been given to the possibility that the behavioral changes brought about by these technologies could prompt a reevaluation of the fundamental principles underlying urban planning. Previously, immersive environments were primarily seen as tools for a limited group of individuals to enhance their problem-solving capabilities within the existing framework of urban planning. However, with the widespread adoption of virtual presence tools, there is a potential for a significant shift in this paradigm. The exact nature and implications of these changes are still not well understood and remain uncertain. However, through the method of behavioral interpolation, we can begin to model the key aspects and potential outcomes of this paradigm shift. The object of this article is to present a theoretical framework for potential transformations in the contemporary urban planning paradigm resulting from the widespread adoption of personalized virtual reality technologies. Through analysis, five key categories within modern post-industrial urban planning are identified as likely to undergo changes: a) residential areas; b) accessibility radius; c) social cohesion; d) transportation requirements, and e) optimal density. Residential units will necessitate additional opportunities and spaces, altering living requirements and lifestyles. The significance of the accessibility radius, particularly for pedestrians, may diminish as a considerable number of desirable locations become accessible directly from individuals' homes. Reducing strain on transportation networks will enhance cities' environmental sustainability and create new opportunities for green spaces. The concept of social cohesion will experience stratified transformations, as differences related to ethnicity, religion, gender, race, age, social status, etc., become neutralized through the development of shifting virtual personas and non-deterministic identities. These interrelated changes will also diminish the weight of the optimal density category. Collectively, these transformations form a comprehensive conceptual framework that reimagines the city. This article outlines two potential directions of change in the urban paradigm that could arise from the proliferation of personalized metaverse communication technologies. The first direction pertains to the contemporary interpretation of deurbanistic concepts, incorporating elements of self-sufficiency, stability, security, and communication infrastructure characteristic of the information age. The second direction is likely to focus on various approaches to transforming the existing urban environment. This transformation will occur through the involvement of market regulatory mechanisms and the development and implementation of specialized municipal programs aimed at modernization and stimulating population growth.
MODERN ARCHITECTURAL PROCESS AND CURRENT TASKS OF ARCHITECTURAL ACTIVITY
The article is devoted to the identification of the features of the modern architectural process and the establishment of actual tasks of architectural activity. Today's society, science, and practice are experiencing phenomena that radically change the approaches and paradigms of the architectural process. The paper highlights the contradictions in the theory and practice of architecture that need to be resolved; considers aspects of the modern ideology of architecture; develops certain provisions of the theory of the environmental approach, namely, the features of "understanding" design, the communicative component of architectural activity; emphasizes the interaction of various actors in the process of architectural activity, the dialogue of the architect with stakeholders. The author emphasizes the decisive role of the architect as an organizer and coordinator of the design process, the interpretation of the architectural process as a component of the overall socio-cultural process. The biggest shifts are taking place in the field of the environmental approach to architectural activity. Environmental issues, which bring people and their lifestyles to the forefront, give impetus to the development of architectural management and marketing. These changes in priorities have led to a problematic situation in the theory of architecture and opened up a new space of work: the identification and recording of environmental experiences and images, the production of these experiences and the management of this process. The environmental approach outlines the future trajectories of architectural work, the essence of which is the inclusion of the designer in the life of the population, the materialization of their own version of life processes, the identification of a set of specialized activities that support the ideology of social progress and cultural development. Scientific research and architectural practice should be based on the achievements of the philosophy of architecture, understanding of new value orientations, taking into account the differences and pace of social change, etc. There is a need to recognize the importance of such a factor as the subject of the architectural process. Changing the basic guidelines of the consumer of an architectural object requires ensuring at the design stage the possibility of transforming an architectural object in the process of its further operation, predicting the emergence of new functions and the formation of their new material shell. The article outlines the contours of scientific innovations in the field of architecture - the theory of architectural activity in the conditions of intersubjective interaction; suggests forms of correct introduction of the concept of "design subject", which is active in the architectural environment, into design practice and theory of architectural activity.
STRUCTURAL FEATURES OF RESIDENTIAL BUILDINGS IN MODERN UKRAINIAN CITIES, BASED ON THE EXAMPLE OF ODESA CITY
The article is devoted to Ukrainian cities that are very different in their history, size, functions and architecture. In the period of crisis and almost complete halt of new housing construction and critical resource limitation, the most promising approaches for the development of residential areas are those that use existing housing structures and available resources. One of the most advanced areas is the use of existing housing structures. Instead of building a new housing stock with new networks and infrastructure, it is possible to develop and compact the existing housing stock (both historical and Soviet), thus reducing the amount of old housing stock and increasing the number of available square metres of housing for city residents. Each city has its own specific history and background, as well as housing structures that were formed at different times. The history of the formation and structural features of the residential development of Odesa city have been studied, so it is important to understand it in the general typology of Ukrainian urban settlements. The main criteria for dividing urban settlements into the types are the following factors: city size, number of residents, historical background, planning structure and functional content. The structural features of the residential development of modern Ukrainian cities are studied, the characteristic features and their impact on the development of residential development are identified. The development strategy for Odesa residential areas has been proposed to create a high-quality high-density living environment in historic cities. The purpose of this paper is to study the structural features of the residential development in modern Ukrainian cities, to determine their characteristic features and influence on the development of the residential development on the example of Odesa. The materials for this study are the structural features of residential development in modern cities. In particular, the impact and consequences of the crisis period on the housing infrastructure and the city structure are considered in order to understand better the crisis contribution to the formation of the modern city. The combination of the research results of the available material base and theoretical foundations of the structural features of residential development in modern cities became the main methodological basis of this work.
residential development of modern Ukrainian cities
ARCHITECTURAL AND URBAN PLANNING ASPECTS OF CITY RENEWAL IN UKRAINE
Cities that are at the epicenter of military conflicts find themselves in an extremely difficult situation. In addition to the most terrible ‒ human losses, the infrastructure of cities, housing stock and industry are destroyed. An extremely difficult task for such territories is their post-war reconstruction. This process can be successful only when there is an understanding of the main approaches and mechanisms for restoration work in such cities. The necessary solution is the development of effective strategies and programs for the reconstruction of cities. This determines a number of priority tasks, namely: analysis of the experience of recovery of the countries of the world after similar destructions and study of the peculiarities of housing reconstruction, as the most acute problem. The article examines the main directions of post-war reconstruction of cities, since post-war reconstruction is an extremely difficult task for any city and country. And for this, it is necessary to determine the priority directions of the restoration and development of cities, depending on the characteristics and nature of their destruction. The restoration of cities should not be limited to reconstruction, but should be decided on a case-by-case basis, taking into account the degree of destruction, the economic component and social reintegration. The experience of countries that have gone through the stages of war and reconstruction is of considerable importance in creating programs for the reconstruction of cities. The set of measures that will contribute to the implementation of programs of reconstruction and provision of housing for the population accretes the world experience. Therefore, the article examines the world experience of the restoration of war-ravaged cities. For partially destroyed cities with a preserved urban environment, it is possible to develop an actual design solution that will take into account the type of reproduction ‒ restoration, reconstruction, or new construction. For territories that have suffered severe destruction, possible options for the implementation of the reconstruction program and provision of housing for the population are: new construction, housing rental, temporary construction of modular or container facilities, formation of a replacement housing fund, compensation for housing. An approach to architectural and town-planning solutions has been developed, which consists in mastering the underground space, the spatial composition of the courtyard space, and the architectural solutions of the buildings.
CURRENT STATE AND PROBLEMS OF FORMING INCLUSIVE SPACES IN THE WORLD AND NATIONAL ARCHITECTURE
The article analyses the current state and problems of forming inclusive spaces in the world and national architecture. The International and Ukrainian regulatory documents that regulate the inclusiveness and barrier-free accessibility for all the population groups are analysed. The concedcpts of "inclusion", "disabled person", "disability", "people with limited mobility", "barrier-free space" are defined. The main organising elements of a quality inclusive environment in all the social spheres are identified. An urgent task is to provide the availability of residential and public buildings for all the citizens, regardless of their physical capabilities. Inclusive spaces of modern architectural development are not only about creating the appropriate infrastructure, but also about transforming the existing one. The purpose of this research is to identify the main elements of the organisation of a high-quality inclusive environment in all social spheres. The necessary analysis of the current trends in the architectural development of inclusive spaces in large cities, as well as the peculiarities of accessibility for people with disabilities and people with limited mobility, has been carried out. Main research methods are comparative and historical analysis; visual and analytical method; monitoring method; analysis of statistical data and qualitative indicators; collection, analysis, presentation, and interpretation of the information on theoretical and practical issues of organising an inclusive environment, which is reflected in the works of foreign and Ukrainian researchers. The findings of the study showed that the developments aimed at solving the problems of creating inclusive spaces are relevant and timely. An important aspect of a barrier-free environment is the development of inclusive spaces in modern cities. The different types of barrier-free environment, including physical barrier-free, digital, educational and economic, social and civic, as well as the information barrier-free, are very important for the development of inclusive spaces in the world and national architecture. Persons with disabilities and people with limited mobility have extremely limited opportunities to realise their rights.
THE IMPACT OF SUSTAINABLE DEVELOPMENT ON NEW CONCEPT OF MODERNISATION OF RESIDENTIAL BUILDINGS
Modernization of multi-apartment buildings is one of the steps towards achieving the goals of Sustainable Development of cities and communities. It is not only energy efficient, but also inclusive and spatial solutions. New concept has been introduced such as "Sustainable modernization" is a harmonious and balanced process that combines coordinated changes in today's and future needs, and "Sustainable modernization of residential buildings" is a complete set of actions for the regeneration of buildings and residential areas, including the regeneration of communal communications and nodes. Because only energy efficiency of buildings is not enough for the achievement of the goals of sustainable cities and communities, considering the fulfillment of all the tasks set. The goal is to make cities and human settlements inclusive, safe, resilient and sustainable. Regeneration today is the modernization of multi-apartment buildings to achieve energy efficiency to conserve and reduce the use of energy resources, which helps reduce utility costs and carbon emissions. But it does not satisfy the task of inclusive and planning decisions as Sustainable Urban Development. Panel mass housing construction heritage makes up a significant part of the country's housing stock in post-Soviet countries. These buildings were built according to standards that do not meet modern requirements and energy inefficient. New concept of regeneration on the basis of sustainable development is proposed as the modernization of residential buildings considering the wishes and needs of co-owners, inclusive and sustainable planning. That is, the architectural and planning decision includes the need for the house and the surrounding area for inclusive and reconstruction taking into account the social needs of the residential quarter.
FEATURES OF THE COMBINATION OF SOCIAL OPPORTUNITIES AND CIVIL ENGINEERING IN URBAN PLANNING
A term "engineering" has his root in the Latin word "ingenium", that means an "intellect" or "talent". It originates from a word "ingeniare", that is translated how to "found" or "invent". Exactly in this Latin expression there is an initial idea about work and ability to decide difficult tasks. There is the nearest to the man, her comfort residence and work. An engineering concept, as disciplines, is constrained with the use of scientific knowledge and technologies for planning, town-planning, architecture, creation and support of the different engineering systems and constructions. In the modern value, engineering embraces the wide spectrum of industries, such as mechanical, electric, computer, chemical, civil, aerospace et al, and has an important value for development of technologies and infrastructures of settlements, that are necessary for modern society. Self-society needs development of different types of engineering, that influence on his normal functioning and steady development. In this context the "civil engineering" is the nearest to the man, her comfort residence and work. A management social process is totality of actions and strategies, sent to influence and organization of the social phenomena, processes and co-operations in society. It includes a management behavior, by activity, relations and other aspects of human life, that take place in public terms. Thus a management social processes ("social engineering") is based on research, analysis and understanding of sociological, psychological, economic, political and cultural aspects of society. Him a primary purpose consists in the achievement of certain social goals and decision of problems, including technical, that stand before society. The basic aspects of management social processes it an analysis and prognostication: careful research and analysis of social processes help to understand their reasons, consequences and tendencies.
ADHESION WHEN USING PARTIAL SHOTCRETE WITH MOBILE EQUIPMENT
The current methods have been analyzed and materials that are used for the repair and renovation of concrete and reinforced concrete elements of the construction of the future. One of these is the considered method of shotcrete, the use of wet shotcrete, its advantages and disadvantages. Defects that occur during the manufacture, storage, transportation, installation and operation of concrete and reinforced concrete structures are given. The formation of different types of cracks that occur before the operation process and the appearance of cracks during the operation of structures under central tension and along one surface during eccentric tension are considered. The work presents regulation of the technical properties of repair mixtures achieved by the use of special types of cement, additives and aggregates, special laying methods and hardening conditions, as well as appropriate preparation of the surface of old concrete. The study is aimed at determining the adhesion of repair mixtures applied by the shotcreting method. Partial application of the repair mixture was used, using a mobile installation in laboratory conditions, in order to determine the optimal technological parameters of spraying. The methodology of experimental studies for determining the adhesion of fine-grained shotcreting using standardized forms with modernized partitions has been developed. Prepared beam halves with a surface angle of 20°, like old concrete, were used to increase the contact area and reduce swirl during shotcrete. A two-factor, nine-point plan of the experiment was developed, in which the thickness of the layer of fine-grained shotcrete (1 cm, 2 cm, 3 cm) of partial application and the speed of spraying of the shotcrete fiber concrete mixture (0 m/s, 35 m/s, 70 m/s) were varied. An experimental study was conducted and the results of the studies were presented.
ANALYSIS OF FACTORS INFLUENCING THE INTEGRITY OF INSULATED FACADES OF HOUSES AND SEARCH FOR METHODS OF THEIR REPAIR
In modern construction, after the insulation of facades over time, the next stage is necessary – their repair. Repair of insulated facades preserves and increases the operational efficiency of thermal insulation systems of facades, ensures durability and improves the appearance of the building. Research results indicate the importance of correct installation and maintenance of insulated facades at the initial stages of construction. It was found that at this stage, various defects can occur, which negatively affect their thermal insulation efficiency and overall reliability during operation. Defects in the installation of insulating materials and other factors can reduce the effectiveness of insulation. The work examines various aspects of the repair, such as replacement of thermal insulation layers, replacement of damaged components and restoration of the appearance of the facade. One of the key tasks is the restoration of the thermal insulation layer, which may be damaged as a result of mechanical or other influences. It is important to inspect in detail, determine the degree of damage and, if necessary, replace insulating materials that may lose their thermal insulation properties in the future. In addition, the restoration of the outer finish layer is the part of the process of repairing insulated facades to ensure an attractive appearance of the building and to protect the internal structural layers, especially the thermal insulation material, from climatic and other factors. It was established that over time, different materials of the thermal insulation layer have different indicators of destruction. Particular attention should be paid to the selection of system materials that have similar vapor permeability properties. This approach will help ensure the necessary properties of the thermal insulation system and keep the appearance of the building in perfect condition for a long period of operation. It has been established that after the restoration of isolated facades, it is important to take care of their maintenance. Properly performing regular inspection and maintenance will help detect possible problems in a timely manner and prevent serious damage in the future. Climate and local building standards must also be taken into account when selecting repair materials to ensure optimal facade performance. In the process of research, it was found that repair methods are chosen, first of all, based on the technical condition of the building and the degree of damage obtained as a result of the survey. This allows you to choose the appropriate repair methods and assess the associated risks. It should be noted that a specialist who carefully examines and determines the state of facade insulation must have certain competencies in the arrangement and repair of facades. Therefore, the research results emphasize the importance of quality repair and maintenance of insulated facades to ensure their reliability, efficiency and durability. It was found that in order to ensure the quality and safety of construction objects, it is important to carry out systematic repair and maintenance of insulated facades, which can be damaged due to various influences. This allows you to preserve the building's energy efficiency and maintain its aesthetic appearance over a long period of operation.
METHODS OF RENOVATION OF MULTI-STORY RESIDENTIAL BUILDINGS IN MODERN UKRAINE
The current situation in Ukraine shows that the restoration of multi-story residential buildings is one of the most important problems of society. Existing research is mostly focused on assessing the technical condition of buildings to extend their service life or repair damage caused by uneven settlement of foundations and other operational factors. Since high-rise reinforced concrete buildings for residential and public purposes were usually designed and built without taking into account possible loads from military conflicts, as well as due to the lack of practical experience in their restoration and strengthening, the issue of ensuring their operational suitability and restoration is very relevant. To the stages of the building operation process, as a single technological process, in the event of damage with: inspections, monitoring, planned, unplanned and major repairs and liquidation. The article analyzed the current state of damaged multi-story buildings, studied the accumulated experience of their inspection, and considered constructive and technological measures for their restoration and reconstruction. The structural features of panel houses make it impossible to replace destroyed or severely damaged structures with new factory elements due to the lack of technical access for installation. The most optimal solution is the construction of new structures on the site of destroyed ones using rolled profiles, reinforcement, monolithic concrete, bricks and aerated concrete blocks. Taking this into account, the perspective for further research is a more detailed study of the problem and the development of structural and technological solutions for the restoration of residential buildings with economic justification of the feasibility of their implementation. In addition, there is a need to supplement the current regulatory documents regarding the reconstruction of buildings damaged as a result of military conflicts.
ANTI-LANDSLIDE MEASURES OF THE SECTION OF THE SLOPE OF THE ODESSA COAST
Calculations of the stability of the section of the landslide slope of the Odesa coast were performed in the work. The site is located in the Kyiv district of Odessa and is adjacent to the children's health and sports camp "Viktoria". The territory covers the coastal part of the plateau, the terraced slope and the beach area. Artificially created terraces and berms stand out in the relief of the slope, at the foot of the slope in some places a preserved natural beach. The specifics of this area are complex engineering-geological (block structure of the slope, loess subsidence soils) and hydrogeological (several aquifers, high level of groundwater) conditions. Previously, before the implementation of a complex of anti-slide measures, large-scale deep sliding and squeezing landslides took place in this area. The partially implemented engineering protection measures, which consisted in the planning of the slope surface and the arrangement of shore fortifications, did not lead to a complete stabilization of the landslide processes. At the present time, undamped, slow-flowing deformations occur on the landslide slope. These deformations are related to the blocky structure of the slope, hydrogeological conditions, as well as rheological properties of meotic clays. Stabilization of landslide processes is possible only with a comprehensive approach in the appointment of anti-slide measures. The assessment of the stability of the slope and the appointment of anti-slide measures were carried out taking into account the features of the engineering and geological structure, hydrogeological conditions, as well as the results of the field survey of the slope. Calculations of the stability of the slope were carried out according to flat schemes by the methods of Bishop and Janbu. Calculations were also carried out in a three-dimensional setting using the finite element method in the Midas GTS NX geotechnical software complex. The Mohr-Coulomb elastic-plastic model described the behavior of the soil in the calculation scheme. The proposed set of anti-slide measures, which includes: installation of absorption wells on the plateau, to lower the groundwater level; arrangement of the lower and upper tiers of key piles with vertical drainage above them; organized removal of stormwater from the surface of the slope; planning and fastening of the slope surface.
EFFECTIVENESS OF DECENTRALIZED HEAT SUPPLY BASED ON TRADITIONAL HEAT GENERATORS WITH VAPOR COMPRESSION ENERGY TRANSFORMATION OF LOW-TEMPERATURE SOURCES
The research is devoted to solving the urgent problem of increasing the efficiency of decentralized heat supply of public buildings and industrial enterprises with typical municipal and industrial heat generators on the basis of heat pump energy conversion of pre-cooling of heat flows of the return energy carrier from the heat network, initial cold water and flue gases. The aim of this work was to analyze and identify conditions that would increase the energy efficiency of the improved system while expanding the total volume of generated heat for decentralized heat supply. Additionally, the work aimed to ensure the environmental friendliness of primary fuel energy use. The proposed approach aims to improve the energy and environmental performance of heat sources by regulating the temperature of the waste energy carrier to its design value, following a standardized temperature schedule. The most important result of the study of the improved system of decentralized heat supply is the established generalized dependence of determining the actual conversion coefficient in the heat pump operation. It allows qualitative analysis of the dependence of energy efficiency of the heat supply system on the temperature change of the analyzed low-temperature sources, the ratio of the above-mentioned water flow rates and the influence of cold water distribution for municipal and industrial-technological purposes. The results of the analytical study of the improved heat supply system create a basis for adjusting the temperature schedule of heat supply, taking into account the characteristic conditions of decentralized heat supply and heat consumption modes of municipal and industrial systems.
STUDY OF STRENGTH AND STRAINS OF COMPOSITE MATERIALS BASED ON FILLED POLYMERS
The article aims to study compressive and bending strength of polymer materials and their strains with various amounts of filler to determine the optimal value. The polymer composite material consists of polymethyl methacrylate as a binder and quartz sand as a filler with the fractions at 0.14 mm, 0.315 mm, 0.63 mm. The filler amounts were changed from 100 to 500 weight parts. The strength of polymer filled material was determined by testing cube samples under compressive and beam samples under bending. The strains were determined by testing prism samples under tensile. The study results show the significant impact of the fraction type on the strength and deformation characteristics of composite materials based on polymethyl methacrylate. The samples with the finest fraction of filler 0.14 mm and 150 weight part demonstrate the biggest strength ‒ 90 MPa under compressive and 40 MPa under bending. The increase both particles size and their amount led to the decrease the strength of filled composite. The analysis of the dependencies between stresses and strains shows than deformations drop as far as the amount of mineral filler declines. In proportion as the quantity of filler goes up, the creep deformations occur under less amount of tensile stress. It is linked the less interaction on the border "filler-polymer" and, as consequences, the bigger possibilities of polymer to plastic deformations. Based on obtained dependencies, the patterns of defect development under loading have been proposed that involves taking into account interphase interaction on the borders "filler-polymer" and "filler-filler". The less the particles size, the bigger their specific surface and structure-forming effect. The increase of sand particles size and their amount leads to growth of porosity, goes down the strength of composite material and drops the capability of elastic recoverable strains. The practical importance of this study is the possibility the usage of the filled polymer composites for recovering and renovation works where traditional cost cement fillers are replaced with cheap and ecofriendly fine sand.