Proceedings of EcoComfort 2024

A significant number of bridges in Ukraine were designed using A-III reinforcement according to typical projects, mainly in the period of the 60s-90s of the last century. Today, these structures have been in operation for more than 50–60 years and are in need of repair due to significant physical wear and tear, improper operation, and destruction during hostilities. The one of the repair options is the replacement of individual destroyed prefab slabs of the run with similar ones, since there are no problems with resting the slab on the supports and the dimensions in height. In such slabs, manufactured according to typical projects, as prestressed reinforcement, reinforcement of class A-IIIв is used. It have manufactured at the factory producing slabs of girder structures from A-III reinforcement, according to GOST 5781 “Hot-rolled steel for reinforcement of reinforced concrete structures. Technical conditions”, by pulling (tensile strengthening). To perform such works, equipment, specialists, regulatory documentation and reinforcement of appropriate quality are necessary. As for regulatory documentation, until 1991 it have developed centrally, after 1991, regulatory documents have often not updated, one has to work with outdated regulatory documents. The absence of valid (active) normative documents can cause the production of low-quality structures.

The paper is devoted to research on the connection between restoration and parametricism, focusing on the design of plinth restoration. Presented is the introductory part of the case study “Sokel” - Test - which deals with the verification of the established hypothesis, whether it is possible to improve the hygrothermal behaviour of the historical building's wet facade wall by means of air flow in existing or proposed ventilated gaps and by morphological by changes of the visually unexposed part of the structure. Using a combination of two-dimensional CFD and HAM simulation, the hygrothermal behaviour of the façade wall with different air flows in ventilated gap is described. The introduction presents the issue, and the proposed methodology is described. Next, the individual steps of the case study building refurbishment design methodology procedure are explained in detail. At the end, the partial results of the research task are presented, and a discussion and a summary of the findings are presented.

The purpose of the study is to reveal the build technologies, techniques of stone processing and carving of architectural details used in the construction of the castle of the 13th century in Kholm. Today castle is a form of archeological ruins. The research methodology is based on a detailed analysis of the remains of buildings and individual construction and architectural details, which were uncovered as a result of more than 10 archaeological studies. The characteristics of natural stones, masonry technologies, techniques of stamping, processing, and cutting of stone blocks and details have been analyzed. Preserved remnants of defensive walls, towers, foundations, and remnants of walls of several buildings present objects created by the group of builders. The excavations revealed a large number of ordinary rectangular blocks and carved decorative details from glauconite stone and limestone, which were used to enrich the architecture and present specific architectural forms of the Romanesque style. The castle was initially built only from glauconite stone. In addition to this local green stone, sandstone, limestone, and fossilized chalk were also used. The research results indicate that a highly skilled stonemasonry brigade worked here, using a standard set of manual tools for that time. Archaeological remains of hewn and carved stone details show a rich plastic arrangement of castle facades and interiors. Similar products and technologies are not found in other contemporary castles in Rus`-Ukraine. The results have allowed to present a detailed characterization of the stonemasonry workshop “Master Avdiy”, a character from the chronicle lines, the author of the castle construction in Kholm for the first time.

The inflow of fluid into collector-pipelines (CPs) increases along the CP according to non-linear law. It is found that under the presence of transit flow at the input of the pressure CP the latter in its initial segment distributes, but not collects, the fluid. A method of regulating the fluid inflow into CP has been invented. According to this method the fluid distribution is transformed into its inflow into the CP. It is proposed that kinetic energy of transit stream which inflows into the CP at its beginning be used for constricting of the fluid stream in inlet nozzle sites. It is recommended to use local constricting inserts. There forms a closed torus – shaped space between the outer surface of the elastic constricting insert and the inner surface of the CP wall. Into this space, the pressure available in the stream in the site in front of the preceding inlet nozzle is supplied. The force of this pressure displaces walls of the elastic constricting insert in radial direction towards the CP axis. The pressure in the site of the inlet nozzle becomes less than that outside the CP. The fluid outflow out of the CP stops and changes to inflow into the CP. This takes place in each inlet nozzle in the site of which an elastic constricting insert is placed.

It is implemented the strength calculation method for normal rectangular cross-sections of shell reinforced concrete elements with flat eccentric compressive strength using the nonlinear deformation model. The main calculation results are analyzed for the case of small eccentricities compression with varying next parameters: concrete classes, the height of the cross section and the reinforcement coefficient. There are investigated the dependence diagrams “bearing capacity Nint – eccentricity of longitudinal force ered” at gradual change of cross-section stress-strain state from eccentric to the nominal central compression. Two typical calculation cases in which calculation collisions occur are investigated. The bearing capacity of the section decreases in proportion to the decrease in the value of external forces eccentricity in the zone of small eccentricities in the first case. It is not possible to determine the bearing capacity in the second case. An alternative technique is to move to the strength determination area, based on the method of ultimate forces. This technique has acceptable accuracy and high speed of calculation. The proposed method is implemented in the “LIRA-FEM” software by a new algorithm for calculating reinforced concrete plate (shell) elements “Wood +”.

Overall, shading loggias play a significant role in enhancing comfort, reducing energy consumption, and improving the usability and longevity of outdoor living spaces in residential buildings. Shading loggias help in diffusing sunlight, reducing glare, and providing a more visually comfortable environment for occupants, especially in work or living spaces near windows. Natural light remains irreplaceable by artificial means. Harnessing the potential of daylight is essential, offering the advantage of free natural illumination within interiors. For the evaluation of the daylighting conditions prevailing in residential building the DF was considered as the parameter for indicating the quantity of admitted daylight. The DF values and illuminance – CIE overcast sky were calculated using DIALux evo 12.1 software. The aim of the paper is to compare three variants of the level of daylight in the rooms of the residential buildings. The results are the influence of different sun shading of loggia on changes in the conditions of natural daylight in the interior of two rooms.

It is known that, regardless of the mechanisms occurring at various levels, what is common to the composite system is the formation of internal interfaces that can transform into cracks. Such cracks are classified as technological cracks, which are present in the sample material before operational loads are applied to them. Of greatest interest is the distribution of shrinkage strains in materials with a network of technological cracks and their effect on the deformability of concrete and on resistance under low-cycle fatigue loading. It is emphasized that the formation and development of technological cracks is determined by technological cracks. This made it possible to qualitatively assess the change in damage to structures and propose a methodology that takes into account the deformation of concrete containing technological and operational cracks in its structure. It is important to study the mechanism of initiation and development of initial cracks under the action of alternating loads, the mechanism of fatigue growth of technological cracks under alternating volumetric deformations of swelling and during a cycle of decreasing the volume of the material, as well as under the action of varying amounts of shrinkage deformations on its banks.Therefore, the study of the transformation of technological cracks into operational ones under the action of low-cycle loads in concrete and reinforced concrete is of particular relevance.

The process of reducing or eliminating carbon dioxide (CO2) emission is a priority in transforming Europe into a climate-neutral continent by 2050. Decreasing the energy use of buildings is a crucial measure to improve their energy performance and reduce emissions associated with heating system. The article gives new insight into certain options to decarbonize the heating installation of large-hall building equipped with the widespread system of gas radiant heaters. Based on a review of technical data of gas radiant heaters and own research some opportunities to improving energy efficiency of the building with regards to the aforementioned heaters were recognized. Action that can be taken include: buildings energy needs lowering, using high-efficiency heating devices, waste heat recovery from flue gases, implementing carbon-free energy carriers like hydrogen, and appropriate building automation and energy management system. Those measures to decrease CO2 emission may be implemented in new as well as in existing hall buildings. Analyses have shown it is possible to reduce CO2 emissions by 5 to 43% and zero CO2 emissions is ensured when fueled by hydrogen.

The article shows the possibility of obtaining fine-grained concrete mixtures and concretes using mechanochemical activated cement-ash binders, which can be used as working mixtures for a 3D printer. The choice of raw materials solve the problem of resource and energy saving, provided that man-made waste is used. Using mathematical planning of experiments, a complex of experimental and statistical models of compressive and tensile strength at the age of 1 day and 28 days describing the influence of factors was obtained. It has been studied that the minimum required compressive strength of a multilayer structure at the age of 1 day is at least 3.0 MPa, which can be achieved by using Portland cement at 10…15% from mass of cement-ash binders and hardening activator at least 2%. The 28-day compressive strength of the concrete is more than 30 MPa. The tensile strength at the age of 28 days is 3.0…5.0 MPa will provide sufficient adhesion between the layers.

The article is devoted to the analysis of approaches to the creation of district heating systems (DHS) in the context of climate threats in the conditions of modern global warming. It is noted that the development of DHS in Ukraine should be aimed primarily at ensuring energy and climate security while increasing their energy efficiency. Attention is focused on the need to introduce modern climate-neutral technologies, which are classified as critical.It is noted that a promising direction for the development of such technologies is the use of forth generation DHS (4GDH). The results of the comparison of the characteristics of these systems and DHSs of the second and third generations (2GDH-3GDH), which mainly include DSTs in Ukraine, are presented.Some attention is paid to the DHS of Ukraine in the aspect of sector coupling, which involves the creation of integrated energy systems, such as energy supply/energy consumption, electric power engineering/thermal power engineering, smart methods of DSM/DSR (demand side management and demand side response), etc.The results of studies on the formulation of the main directions for the development of DHS as a critical technology for the development of low-carbon energy are presented.

An analysis of the results of scientific research on dynamic loads, their characteristics and their impact on the structures of buildings and bridge structures is presented. Theoretically and experimentally confirmed dependences for determination of strength and deformation characteristics of high-strength concretes under dynamic influences are proposed. That allows to determine the characteristics of high-strength concrete under different types of stress-strain state. The possibility of determining the deformation characteristics of concretes depending on the compressive strength and the coefficient of dynamic strengthening is proved, which allows to simplify engineering calculations for dynamic loads. The obtained dependences are confirmed experimentally. Resistance of concrete to dynamic effects is characterized by the concept of explosion resistance. Concrete breakdown or penetration on impact is characterized by the coefficient of susceptibility to penetration. This coefficient also depends on many material parameters: hardness, strength, deformability and density. The possibility of obtaining reliable data on a simple coprop equipment in the laboratory is substantiated.

Ukraine possesses significant land resources for agriculture, which allows not only to provide the population with food but also to produce raw materials for bioenergy. Agricultural waste and residues, such as straw from cereal and leguminous crops, corn and sunflower seeds, sunflower husks, sugar beet pulp, and fallen leaves, can be used as raw materials for bioenergy.In the production of gaseous fuel from fallen leaves, not only energy in the form of biogas is generated, but also high-quality fertilizers that can be used for personal needs or sold to farms. Biogas production takes place in bioreactors of various designs, differing in shape, material, mixing methods, heating of biomass, and the volume of raw material processing.The article presents a graph of thermal capacities and the distribution of heat flows in a bioreactor, as well as dependencies for determining heat flows on flat and cylindrical surfaces. The current state of fallen leaf utilization is examined, and a method of anaerobic fermentation is proposed. The main factors influencing methane formation are studied, and the calculation of biogas production is presented. The productivity of the bioreactor is determined depending on the temperature of the raw material and the hydraulic retention time.

The article discusses improving energy efficiency in ventilation systems through optimal selection and placement of elements downstream of the radial fan. To reduce costs and improve reliability, it emphasizes installing optimal designs with enhanced aerodynamic characteristics. Key elements include flexible inserts and diffusers, positioned immediately after the radial fan to manage uneven velocities, turbulence, and swirls. Recommendations are given for placing various components, such as flat symmetric, asymmetric, pyramidal, and step pyramidal diffusers, as well as flexible inserts and branches. The authors suggest changing the conventional arrangement of these elements, which are typically located immediately after the radial fan.Discharge flow equalization is recommended for radial fans in both suction and discharge modes, with backward and forward-curved blades, particularly effective in injection systems and fans with forward-curved blades. Equalization tools are especially effective in variable operation modes with frequency converters. Technical and economic comparisons show significant efficiency improvements. Using flow equalization tools compared to systems without them and with existing frequency converters yields a 9.8% economic benefit with a 0.2-year payback period. Combining flow equalization and frequency regulation provides a 12.5% economic benefit with a 1.8-year payback period.

The purpose of the research is to check the effect of adding photocatalytics nanomodifiers TiO2 on the physical and mechanical properties of gypsum plasters. It is shown that the use of nanosized titanium dioxide is one from ways of obtaining composite gypsum finishing plaster with improved mechanical and photocatalytic properties. The use of nano-sized doped titanium dioxide creates photocatalytic layer on the surface of the material that is activated by ultraviolet or visible light. With the help of nuclear power microscopy of microcracks and three-dimensional topography of the surface of gypsum plaster the presence of botryoidal agglomerates of titanium dioxide was established. The study of the macrostructure of the chips of gypsum binder compounds established that the pores of the composition with 2 wt.% TiO2/S,C contain agglomerates of doped nanocomposite, which compact the microstructure by filling the pores, which increase the mechanical properties of the material and reduce the possibility of cracking. Gypsum plaster, modified with nanomodifier TiO2/S,C, became 54% stronger than the control sample. When analyzing Raman spectra of gypsum plaster of additive-free composition and composition, modified 2 wt.% TiO2/S,C, it was established that the modified sample characterized by the presence of anatase titanium dioxide.

This article presents a reconstruction procedure for prefabricated reinforced concrete floor slabs in a multistorey apartment building in Lviv (Ukraine). These floor slabs were exposed to enormous fire loading and were damaged due to explosions from two shells. The study revealed that the detected defects and damages significantly reduce the reliability and rigidity of floor slabs because of the loss of bond strength between the principal reinforcement and concrete. As a result of fire loading, the study also determined that there was a loss of prestressed and design resistance in the principal reinforcement. This research aimed to investigate how temperature fluctuations affect the stiffness of the studied floor slabs. The rigidity of floor slabs was related to the level of its fixed deflection (its value was 14.5 mm), determined under the action of only a constant load from its weight. In this article, the strengthening of damaged floor slabs is proposed by arranging cages of reinforcement in the hollows of slabs and increasing their effective height and correspondingly compressed zone at the expense of a monolithic reinforced concrete slab.

The results of experimental studies of the strength of concrete with the BERAMENT A2 additive based on melamine compounds aged up to 28 days based on M400 cements of the second group with mineral additives up to 40% produced by Kryvyi Rih Cement, Mykolaiv Cement, Podilsky Cement, Ivano-Frankivsk Cement plants, modified with the BERAMENT A2 additive are presented. The strength of concrete was determined by testing cubes for uniaxial compression at the age of 1, 7 and 28 days. Tables of the strength gain of concrete with different doses of additives (0.6; 1.2; 1.8; 2.4%) by weight of cement are given. A comparison was made of the rates of strength gain of concrete using domestic M400 cement and Rohoznik cement (Slovakia) depending on the amount of additive. Based on the conditions for ensuring the required hardness of the mixture, the upper and lower limits were established, as well as the optimal dose of the additive for each of the cements, which had mineral additives of up to 40%.

The manuscript delineates the outcomes of investigations concerning the uniformity of airflow velocity resulting from the interaction of opposing non-coaxial circular air jets. Within this study, the characteristics of air jets formed by the collision of opposing non-coaxial air streams are detailed. Notably, the manuscript delves into the determination of the coefficient of uniformity governing the exit velocity of the resultant air jet, alongside the derivation of empirical equations aimed at quantifying airflow velocity uniformity. The primary objective is to explore the uniformity of velocity within the resultant airflow, generated through the interaction of opposing non-coaxial circular air streams, and to construct a mathematical model elucidating the dynamics of round aerodynamic flows within a designated space. Graphical representations and empirical formulas, derived from experimental investigations, are presented within the manuscript. Velocity field analyses were conducted to assess the uniformity of airflow output resulting from the interaction of non-coaxial opposing circular air jets. The utilization of the effect stemming from the interaction of opposing non-coaxial circular air jets ensures a notable initial intensity of turbulence, a considerable attenuation of airflow velocity within the resultant flow, and a pronounced degree of uniformity in its exit velocity.

The object of research is gas networks. The problem of sustainability of objects of distribution and gas systems is being investigated. The developed software makes it possible to estimate the gas imbalance in complex gas systems of the network type and the volumes of gas emissions into the external environment in case of emergency situations. The software includes all facilities, their information and detailed mathematical models, which provides non-stationary modeling of gas networks and underground gas storages. A feature of the software is the substantiation of the proposed approaches for the guaranteed detection of gas imbalance in closed gas systems based on flow and pressure measurements. The software has been tested in real operating conditions to assess the hermeticity of subsystems of gas transmission systems and emissions during emergency situations at underground gas storage facilities.

The study aims to evaluate the effectiveness of restoring RC beams using the high-strength mortar Sika MonoTop 4012. Considering the importance of the load-bearing capacity of reinforced concrete structures in civil engineering, this work focuses on restoration methods that enhance their strength and durability. The primary objective of the article is to conduct experimental research to determine the efficiency of restoring damaged RC beams, as well as to describe the methodology for performing these works. The study analyzes modern approaches and materials, including the use of high-strength mortars that significantly improve structural integrity and load resistance. The experimental results demonstrated that the application of Sika MonoTop 4012 and other materials effectively restores damaged areas, ensuring the reliability and safety of further exploitation of the structures. Additionally, the study investigates the propagation of cracks in concrete and the behavior of beams under various loads. The novelty of this research lies in its comprehensive approach to the analysis of RC beam restoration using modern high-strength materials. The developed methodologies can be utilized by both engineers and researchers for further scientific and practical developments in this field. The experiment resulted in restoring the load-bearing capacity of a destroyed RC beam to 131% of the depletion level of an undamaged beam. The findings of the study are significant for the development of modern civil engineering and can serve as a basis for ensuring the reliability and durability of building structures under prolonged operation and exposure to aggressive environments. Thus, this research makes a substantial contribution to the advancement of RC beam restoration technologies, offering effective solutions for ensuring their functionality and safety.

The presented results encompass an analysis of experimental data obtained from determining the bearing capacity of reinforced concrete beams with rectangular cross-sections, featuring damage in the compressed zone of concrete. During the conducted investigation, 15 reinforced concrete beams with dimensions of 100 × 200 × 1200 mm were tested for bearing capacity, exhibiting varying degrees of damage and relative shear span ratios av (within the range of 1d, 2d, and 3d). Statistical processing of the laboratory research results was performed utilizing regression analysis, and based on the obtained results of the ultimate shear force Vu, a three-factor nonlinear experimental-statistical model was constructed. The results indicate that the relative shear span ratio exerts the greatest influence on the ultimate shear force, followed by the angle and height of damage to the element. It was established that as the damaged area increases, the width of crack opening decreases. Furthermore, samples with similar damaged areas but differing ratios of damaged height to damaged angle exhibit varying widths of crack opening. Additionally, it was found that the initial cracks do not form simultaneously from the parallel faces of the element when damage is present near one of the faces; they also exhibit varying widths of crack opening.

This paper extensively explores the integration of renewable energy sources and green elements into building design, with a specific focus on the impact of biosolar roofs. In response to the escalating demand for sustainable energy solutions, the adoption of biosolar roofs emerges as an innovative strategy for harnessing solar energy while concurrently promoting biodiversity and greenery within urban landscapes. Through a meticulous examination of literature and comprehensive case studies, this study meticulously scrutinizes the technical feasibility, environmental benefits, and economic viability of the system. The findings illuminated through this exploration reveal the substantial potential of this system in mitigating carbon emissions, curbing energy consumption, and bolstering the overall sustainability quotient of buildings. By leveraging the natural resources available, biosolar roofs not only contribute to reducing the carbon footprint but also foster a more environmentally conscious built environment. Ultimately, this paper serves as a comprehensive guide shedding light on the multifaceted aspects of the system, from their technical intricacies to their ecological and economic implications. It promotes a comprehensive strategy for sustainable building practices, highlighting this roofs as crucial elements in advancing a greener, more sustainable future for urban environments.

This article introduces a novel approach to calculating buildings and structures for the impact of air blasts. We showcase the use of modern calculation methods such as direct integration of equations of motion, shock impulse method, and quasi-static method. Our innovative method, utilizing explosion accelerograms, proposes a new way to assess the elastic-strain state of the frames of buildings and structures under the action of shock airwaves. We derive the horizontal accelerations of the earth’s surface oscillations from the verified known dependences of the vertical velocity of the earth’s surface on the value of the pressure from the explosion. The key advantages of our method are its simplicity, validity of the physical essence of the air blast, ability to assess the impact of the blast wave of a specific type of ammunition, sufficient accuracy for engineering calculations, and consideration of the geological characteristics of the site. Our method allows for the calculation of the stress-strain state of the frames of buildings and structures using accelerograms of explosions with the use of most software packages for which the possibility of taking into account seismic effects using accelerograms is implemented. We verify our method by comparing it with the impulse method of calculation.

Nowadays, many cities are struggling with overheating, mainly because cities are growing, urban development is becoming denser and greenery is disappearing from cities. There are several ways in which we can improve the urban environment. However, not every city struggles with the same conditions and therefore the principles of urban design and mitigation are different. The simplest and oldest way to reduce temperature is to use green space and cool it down by shading, or even evaporation. In addition, greenery has other benefits such as improving air quality, visual effect and acoustic comfort. Around the world, various organisations are working on this area and cities are following their own legislation. Although the legislation is already in place around the world, each city needs a different approach to the regulations. An individual approach for the design and application of green spaces is important in urban planning. New technologies and approaches to green architecture can also be used for new developments. However, a different approach will be needed for buildings to be renovated. However, before policies can be developed, urban green space needs to be analysed, broken down and analysed. In this paper I will discuss the analysis of urban greenery in the city of Košice.

Considering the wide operation of reinforced concrete (RC) structures under the impact of aggressive environments, compound experimental studies of different strengthening techniques have reached their topicality recently. However, experimental investigation on a large number of samples requires significant technical, material and time resources, resulting in important limitations. This reveals the growing necessity of efficient design of experiment, focusing on the most important and excluding less important parameters from the research program. This research aims to fill this challenging gap of knowledge by simulation-driven research program development performed with the use of the Ansys DesignXplorer application integrated in Ansys Workbench. As the main object for design exploration is chosen the RC beam with corrosion damage of rebar, subjected to bending loading. It was considered that the beam is strengthened with carbon-fiber reinforced polymer (CFRP) tape with different dimensions, serving as the input parameters. Automatic goal-driven optimization of the response surface enabled identification of the potentially influential parameters of the studied structure and feasible changing parameter for further experimental study. Also, sensitivity and correlation analysis were performed, facilitating the general understanding of the relationships between input and output parameters Furthermore, the robustness of the structure was assessed with the probabilistic analysis according to 6σ- criterion.

High-quality room lighting has great potential for improving the quality of life. However, if grounded on imperfect knowledge, it can cause unintended harm. This issue is of particular relevance against the background of rapid spread of chromatic LED illumination in the modern lighting design. The article proposes and theoretically substantiates the appropriateness of an interdisciplinary study of the aesthetic, psychological and physiological influence of chromatic light environment on a person. It has also been identified that the basic conditions for practical implementation of this interdisciplinary study include the provision of the integrated impact of chromatic illumination on the user, both through the organs of vision and through the skin, in the framework of the study environment; organization of a chromatic light environment which is integral, continuous and devoid of any additional semantic layers; eliminating possible manifestations of discomfort glare and visual disability of users by means of using a space consisting of interior surfaces with uniformly scattered illumination of moderate brightness; simultaneous comprehensive analysis of the aesthetic, psychological and physiological effects of colored light on users in their environment.

The article presents an instrumental survey with the necessary engineering and technical solutions for removing from the emergency technical state of the architectural monument “Walls with the Stations of the Cross and Chapels” on the territory of the Zamochok tract in the city of Belz, Lviv region. The researched complex of sacred buildings of the Zamochok tract is located on the site of an ancient princely citadel (dytynets) dated back to the 10th–13th centuries (of the city of Belz), called in old documents Zamchishche, from the end of 19th century called Zamochok. The architectural monument includes the “Stations of the Cross” fence with 14 stations and two open chapels. According to the direction of the cardinal points, the sacred buildings of the Zamochok tract consist of the eastern wall (southern and northern parts), southern and western walls, eastern and western chapels. All the masonry spans need strengthening due to the destruction of the plinth masonry surface, the presence of cracks and subsidence in it, some sections of the masonry are lost to the soil surface by 15%. In addition, the western span is in an emergency technical condition as it has significant subsidence of structures, deviations from the vertical, numerous cracks and loss of masonry (75%). The eastern chapel is not suitable for normal use due to its deviation from the vertical up to 20, the western chapel is in a state of emergency, its roll is about 10.60.

Understanding how structural elements such as beams, columns, and walls respond under loading is essential for designing efficient and safe structures. This article presents a study where a reinforced concrete beam is simulated and analyzed using Finite Element Analysis software, specifically ANSYS. The beam model, measuring 2100 × 200 × 100 mm, incorporates one 20 mm diameter bar for primary reinforcement, two 6 mm diameter bars as hanger bars, and 6 mm diameter bars spaced at 75 mm intervals for shear reinforcement. The behavior of the analyzed beam is assessed in terms of flexural behavior, crack formation, and displacement under various loading conditions ranging from 10.8 kN to failure load (36 kN). The analysis reveals that the results are highly influenced by factors such as mesh density, material properties, and load increments. Methodology of work. As a basis for the comparative analysis, 5 experimental samples of reinforced concrete beams were taken and their research results were processed. For the next stage, similar reinforced concrete beams were modeled in the ANSYS computer in a non-linear setting using FE elements SOLID65 and Link 180. Results. The optimal version of the calculation scheme was proposed, and after the calculation, graphical dependences of the stress-strain of the samples under the action of the load were created.

The NUWEE dormitories were built in the last century and do not meet the current requirements of energy consumption. The condition of the constructions of building elements and engineering systems of the NUWEE Dormitories # 1–6 and measures to increase their energy efficiency were analyzed. The assessment of energy consumption before and after the implementation of energy efficiency measures of Dormitories # 1–6 was made and the predicted saving of energy resources after the implementation of these measures was determined. The ranking criteria of energy efficient measures were defined and analyzed such as Financial Ranking Criteria (FRC), Environmental Ranking Criteria (ERC) and Behavioral Ranking Criteria (BRC). Implementation of the proposed energy-efficient measures will reduce energy consumption and related costs by 44% in average (compared to the basic level of energy consumption). Buildings of Dormitories # 2, 4 can achieve energy efficiency class B after the implementation of the proposed measures, the buildings of other dormitories can achieve energy efficiency class C. The implementation of energy efficiency measures in the complex will have the payback period from 14 to 16.4 years. The implementation of energy efficiency measures will also result reducing the emission of greenhouse gases by 40% in average.

Pressure distribution drainage pipelines are one of the main elements of reclamation systems, ensuring optimal moisture conditions for agricultural production. The aim of the work is to develop a reliable methodology for hydraulic calculation of the investigated pipes, taking into account the structural and filtration characteristics of the surrounding soil and the lateral surface of the pipes. The research utilized a combination of experimental measurements and analytical processing of the obtained data, complemented by the results of solving the initial theoretical dependencies describing the fluid motion with variable flow rate in pressure distribution drainage pipes. Relatively simple and convenient calculation formulas were obtained, allowing the determination of effective characteristics of distribution drainage pipes, namely, diameter and length. The proposed calculation methodology will be useful in real-life design of distribution drainage pipelines in reclamation systems, as it allows for rational calculation of their parameters, significantly reducing construction costs and ensuring optimal operating conditions of reclamation systems.

The article researches the properties of modified fine-grained concrete containing different types of fibres and fly ash. The effect of different types of fibres on the flexural and compressive strengths and shrinkage deformations of concrete modified with polycarboxylate superplasticiser was investigated. The results showed that the use of straight long steel and polymer structured fibres made it possible to obtain composites with increased flexural strength.The study shows that in order to achieve high flexural strength and low shrinkage in cement concrete with high-strength fly ash matrices, it is necessary to combine steel and polymer fibres. The combined addition of SA l/50 + PMS l/50 fibres to the modified concrete with a content of 40% by mass of fly ash provides an increase in flexural strength by 23.9-18.0% at all curing times. It was found that the addition of 40% by mass of fly ash can reduce the shrinkage deformation of modified fibre-reinforced concrete of all compositions. The modified fibre-reinforced concrete with FA is characterised by a dense meso- and microstructure. The introduction of PCE and an increased amount of fly ash provides a dense contact zone between the cementitious matrix, fibre and aggregate. The use of fly ash in modified fibre-reinforced concrete provides technical, economic and environmental effects in construction.

Prefabricated crossbeamless slab-ribbed span structures are common in construction practice. They were designed in the Standard Design Issue 56D (supplement). This design has a number of advantages and disadvantages. Due to the advantages, such span structures have been successfully used in Ukrainian construction for many years. However, at present, most of them do not provide sufficient bridge deck dimensions and load capacity, so they need to be strengthened and rehabilitated in accordance with modern requirements. The method of reconstruction of such bridges using an overlay slab with cantilevers allows for both widening and reliable strengthening of the span structure. A monolithic overlay slab with cantilevers is installed on top of the existing girders. For reliable joint work, the slab and girders are connected by flexible anchors. A special feature of this reconstruction method is also a change in the static scheme of the span structure. The girder sectional static scheme becomes a beam- or frame non-sectional scheme with rigid bearing nodes. The article describes the design solutions and technical condition of existing crossbeamless bridge spans built in accordance with the standard design of issue 56D, as well as effective solutions for their reconstruction and the results of in-situ tests of such bridges before and after reconstruction.

International and European trends soon foresee a significant reduction of carbon dioxide and methane emissions and a transition to technologies based on renewable energy sources. One of the strategic tasks of the sustainable development of gas transportation systems is to reduce the technological consumption of natural gas, including methane leaks into the atmosphere from gas transportation systems. Therefore, the article considers very important issues of technical, economic and environmental protection related to the detection and reduction of possible leaks of natural gas from damaged gas pipelines. An improved mathematical model of steady-state gas movement is proposed, which enables the calculation of gas parameters along the gas pipeline and at the point of damage. Using the equations for calculating the gas flowrate during its leakage through the hole into the air enables the determination of the amount of gas loss through the damage. A methodology has been developed for determining the amount of gas lost from a gas pipeline with existing damage under conditions of incomplete information about the gas pipeline. The obtained results make it possible to increase the accuracy of determining the amount of losses and reduce the time of damage detection, localization and elimination.

Managing stormwater allows for much more efficient use of water resources, improves operational performance indicators of wastewater systems, and normalizes the hydrological regime of the river into which treated wastewater is discharged. One of the structures that allows for effective regulation of peak loads on the system and partially or completely purifies surface runoff is a stormwater tank. The work describes the mathematical modelling of the filling and emptying processes of the multi-section stormwater detention tanks (SWDT). Dimensionless regulating volume coefficient Kreg and several the constructive parameters: the coefficient of area ratio k, the dimensionless diameter of the outlet pipe Dc′, the dimensionless filling of the SWDT h′, initial regulation coefficient αс,о. The results of the computer program for determining of the regulating volume coefficient Kreg depending on dimensionless coefficients are presented. The obtained results of numerical experiments were approximated by a linear dependence with a high degree of correlation.

Proper positioning of tower cranes at the construction site leads to increased labor productivity and reduces transportation costs within work zones. Tower crane planning procedures include selection, placement, and operation. Planning the sequence of tower crane usage begins at the early stages of construction projects and serves as the basis for making further decisions, both for dynamic and static models of construction sites. However, due to the dynamic structure of factors determining site parameters, such planning is often complex and inefficient. Choosing the wrong spatial placement of a tower crane solely based on constraints, guiding factors, or previous experience can result in additional costs and project delays. Utilizing modern information modeling technologies combined with optimization methods can make the process of spatially locating tower cranes more efficient and precise. These technologies help visualize the spatial placement of all construction assets on the site throughout the project implementation period, ensuring better results for both physical space utilization and machine technical specifications.The main goal of this work is to synthesize scientific experience in optimizing the selection of tower cranes, their type, quantity, and placement on the construction site.

In the manuscript, findings pertaining to the aerodynamic effects resulting from the collision of opposing non-coaxial air jets are delineated. The paper presents an examination of the attenuation coefficients characterizing the resultant airflow arising from the interaction of opposing non-coaxial air jets. Empirical equations aimed at determining the attenuation coefficients with respect to velocity and temperature of the resulting airflow have been derived. The primary objective is to investigate the attenuation coefficients pertaining to velocity and temperature within the resultant airflow and to formulate a mathematical model describing said airflow under both stationary and variable indoor climatic conditions within an enclosed space. Graphical representations depicting dependencies and empirical equations derived from experimental investigations are provided. Furthermore, parameters concerning both flat and circular air jets, and their leakage under both stationary and variable operating modes within an enclosed space, are elucidated. Additionally, the rationale behind determining the turbulent transfer value for the purpose of substantiating the coefficients governing velocity and temperature attenuation within the resultant airflow is expounded upon.

In today's wartime, one of the key issues of Ukraine's construction industry is to rebuild road infrastructure. However, outdated approaches to the management of natural resources lead to their devastating depletion, slowing economic growth and the implementation of European construction standards. The direction of scientific research on the use of technogenic waste as a material resource in the road industry is relevant and progressive. The overall purpose of this work is to investigate the possibility of utilizing phosphogypsum by creating a composite material based on it for constructive layers of road pavement. The choice of components for the composite material was based on the principle of creating rigid mixtures based on raw phosphogypsum stabilized with mineral substances, namely ground granulated blast furnace slag and Portland cement, which corresponds to the concept of sulfate-alkaline activation of slag. The investigation of the phase composition and microstructure of the composite material indicates the formation of calcium hydrosulfoaluminate and calcium hydrosilicates in the cementing matrix. The formation of hydraulically active phases contributes to the gain of strength and frost resistance, and ensures the achievement of water resistance. It has been established that composite materials based on phosphogypsum correspond to the criteria of the national standard of Ukraine (DSTU 9177-3:2022 Part 3: Materials reinforced with mineral binders) for the constructive layers of road pavement.

Transport infrastructure plays a crucial role in the economic and defense capabilities of a state. One of the prerequisites for the safe passage of vehicles is the proper technical condition of the infrastructure, especially on roads and railways. The most common types of transport engineering structures are concrete pipes. However, the majority of concrete pipes are subjected to long-term exposure to variable environmental conditions and loads from transportation, leading to damages and defects in the pipes. The occurrence of defects and damages results in decreased capacity for traffic flow and transportation efficiency. Consequently, repair measures are required. The technology for strengthening concrete pipes using modern structural solutions is provided, along with a justification for selecting the appropriate technology for strengthening defective concrete pipes. A methodology for assessing the stress-strain state of strengthened concrete pipes using the finite element method has been developed. The stress-strain state of strengthened concrete pipes has been evaluated using the finite element method with the FEMAP with NX Nastran software package. Through the investigation, it has been established that in theoretical calculations, the maximum discrepancy in deformations compared to experimental testing does not exceed 10%. This confirms the effectiveness of utilizing the finite element method for predicting the behavior of strengthened structures using the sleeve method and can be considered a reliable tool for engineering analysis in similar studies. The obtained results can be practically utilized for repairing defective concrete pipes during operation.

This article presents the methodology and results of the experimental study of the aerodynamic characteristics of the air solar collector, in which carbon textile, enclosed in the form of corrugation, is used as an absorber of solar energy. Variants of methods of laying carbon textile in a solar collector are presented and analyzed. Theoretical data on aerodynamics in a flat channel formed by smooth surfaces and knitwear material enclosed in it are given. Insufficient convergence of the known criterion equations applicable to flat smooth channels is indicated. The dependences of the change in the pressures difference before and after the air heater on the change in air flow rate when the corrugated carbon textile is placed along and across the direction of air movement were obtained, and the values of the coefficients of friction factor were determined for different laying methods. The optimal method of laying corrugated carbon textile from the point of view of aerodynamics is formulated, the necessary opening angles of the corrugations and the location of the waves relative to the direction of air movement are given. Criterion equations for determining the coefficient of friction factor in the channel formed by two flat plates and a corrugated carbon textile laid in the channel at different corrugation opening angles have been determined (corrugation opening angle).

The use of alternative materials, such as waste, as a replacement for ordinary Portland cement ensures economical and sustainable production of concrete with minimal hazardous impact on the environment. In this study, ash from peat combustion is used to replace some proportion of Portland cement in concrete. The properties of the fresh concrete modified with superplastisizer and the strength of concrete were studied when 5, 10, 15 and 20 wt.% of Portland cement was replaced by peat ash. It is shown that the introduction of ash instead of a part of cement into concrete in the amount of 5 and 10 wt.% does not affect the consistence class of fresh concrete. Adding of ash instead of a part of cement into concrete with a strength class C30/35 causes a decrease of the strength of concrete after 2 days of hardening by 7–18%, and a slight decrease of concrete strength with peat ash is observed after 28 days of hardening without changing the strength class.

The article considers the important issue of protecting the adjacent areas of pumped storage power plants (PSPPs) by ensuring the reliability of their hydraulic constructions. For calculating the height of translation waves that occur during the start up and stop of hydraulic units it is used a two-dimensional mathematical model based on the Saint-Venan differential equation. It was shown the results of full-scale research and numerical simulation of parameters of translation waves in the upper water reservoir of Dniester PSPP during operation in pumped and turbine modes. It was determined the shortcomings of the numerical simulation and suggested to improve it by using a correction coefficient that takes into account the presence of lateral water inflow into the main flow. The comparison of results showed their good convergence. Full-scale measurement of translation waves is based on the readings data from pressure sensors of type VEGAWELL72 installed in the upper reservoir of the Dniester PSPP. The necessity of improving the method of calculating and full-scale research of translation waves during the designing, building, and operating the PSPP was justified.

Decarbonization of engineering networks of buildings of various purposes is necessary to achieve the European Union’s goal of zero greenhouse gas emissions by 2050. One of the directions of decarbonization of the energy sector is the introduction of radiant cooling systems, which allow the use of renewable energy sources and reduce the heat load on the ventilation system. For the wide implementation of radiant cooling systems, an accessible method for determining their cooling capacity is necessary. The article is devoted to the solution of the urgent task of developing an engineering methodology for determining the cooling efficiency of the cooling beam panel. The method is based on the requirements of Ukrainian regulations regarding the calculation parameters of indoor and outdoor air, existing methods for determining heat gains into the room and information of the latest research on heat transfer coefficients and heat transfer coefficients of cooling panels. The advantages of the proposed engineering methodology are universality, informativeness, accessibility for engineers. It enables a comprehensive approach to the selection of radiant cooling devices for specific premises.

Smart Buildings technologies are used to increase energy efficiency, environmental protection, occupant comfort, offer security and access control. Such systems allow reducing operating costs of residential buildings. In addition to the clear benefits of smart building technologies that enhance our daily lives; their increasing complexity can lead to occasional malfunctions. Hence, it’s prudent to use processes observed in natural systems alongside the advancement of high-tech solutions. Modern achievements in materials science make it possible to create Smart Concretes, which are energy-harvesting systems that are capable of generation, storage, transformation of electrical energy and imitate natural processes. Smart Concretes are classified according to their multifunctional properties. Smart concrete presents a unique chance to design multifunctional building structures that blend conventional roles like load-bearing and enclosing with the innovative capabilities of generating, storing, and converting various forms of energy such as electrical, thermal, electromagnetic, mechanical, and light energy. A method for testing the electrical conductivity of Carbon Nanomaterials (CNMs) as aggregates for electrically conductive concrete has been developed. According to the developed method, the electrotechnical indicators of carbon fillers, such as coke breeze and carbon black, were studied.

The article is devoted to the application of hybrid solar collectors integrated into the transparent facade of buildings. Energy-efficient buildings’ heating using renewable energy sources, particularly solar energy, is an important task. Solar collectors cannot always be installed on buildings due to limited space, so it is perspective to use solar heating systems when their elements are combined with structures of external building enclosures. The article provides the main definitions of a transparent building facade and gives a classification of types of glass and selective coatings depending on their application, application methods, and temperature properties. The authors propose the design of a hybrid thermal and photovoltaic solar collector and propose a mathematical model of a heating system with such a solar collector based on thermal performance. This article focuses on determining the fill factor of the volt-ampere characteristic. The information provided here indicates that the mathematical model of heat exchange processes in a hybrid solar collector requires experimental data.The article points to the need for the use of hybrid solar collectors to ensure the effective collection of solar energy and emphasizes the importance of further research and improvement of the constructional elements of such systems to reduce environmental pollution and increase the resilience of heating systems.

The scalability and replicability analysis is aimed at the assessment of the performance, reliability, and efficiency of the proposed solutions for the Intelligent Building Management Systems for handle more data, users, or transactions as well as the ability to be reproduced or replicated in a consistent and reliable manner. This study evaluates the outcomes of the Horizon 2020 PRECEPT Project which is aimed at transformation residential buildings into proactive and efficient ones using intelligent approach to manage the energy consumption and occupants’ well-being. Five residential buildings in diverse locations across Europe represent the Pilot Sites involved for demonstration and analysis of the PRECEPT scaling-up and replication potential. The adopted methodology is based on the existing literature and involves gathering specific data through questionnaires in the form of multiple-choice questions which were completed by project managers. The overview is provided with a plain evaluation on how different factors impact scalability and replicability as well as limitations and barriers that could influence the implementation of the project results are summarized.

The manuscript presents research outcomes aimed at enhancing the efficacy of natural ventilation systems within residential building premises. The primary objective encompasses investigating the aerodynamic properties of buildings within a wind tunnel setting, with the overarching goal of devising a mathematical model to compute the requisite airflow volume necessary to establish a comfortable indoor climate. This mathematical model, predicated on the solution of transcendental equations, has been developed. Analytical expressions derived from experimental findings are outlined. Moreover, aerodynamic characteristics pertaining to both tidal and exhaust airflow within the context of natural ventilation within a room have been discerned. The utilization of transcendental equations as a methodological approach for ascertaining a room’s natural ventilation is justified. The proposed methodology, revolving around the solution of transcendental equations, ensures a high degree of accuracy and aligns closely with experimental and theoretical paradigms. Universal equations for calculating natural ventilation within a room have been derived, further refining the mathematical model underpinning such systems.

The article describes the test of a flat plate made of PLA plastic, made by the method of 3D printing, for deformability. An analysis of available scientific research related to constructions made by the 3D printing method was carried out. To solve the research problem, a prototype of a flat plate was made from PLA plastic using 3D printing technology. For conducting experimental studies, a device was developed to test the plate sample under study. To determine the calculated values of displacements, a calculated finite-element model of a flat plate made of PLA plastic was created in the PC “LIRA-SAPR”. The calculation model of the plate consisted of typical finite elements and nodes. The conducted experiment made it possible to obtain the results of the study of the plate for bending, namely the deflection of the plate. According to the results of the experimental study, graphs of vertical movements were constructed, taking into account all stages of loading. The analysis of the obtained results made it possible to establish that the strength of the plate made of PLA plastic is ensured at deflections that significantly exceed the permissible values. A comparison of the experimental values with the calculated values was carried out and a good convergence of the results was obtained.

New constructions of partitions, made with an inner layer of heat-insulating porous concrete and surface layers (structure) of sheet building elements of non-metallic or composite origin, standard or reinforced with non-metallic composite reinforcement based on basalt or glass roving, obtained by the method of industrial serial assembly of elements on semi-automatic equipment, quickly conquered the market due to the ease and speed of installation, as well as the relatively low cost of construction. However, there are no studies of such panels, which would help engineers implement them more widely in construction and more effectively choose the necessary partition structure for certain premises of buildings. This article presents the results of experimental studies of the operation of metal dowels in three-layer aerated concrete panels with a non-metallic sheet coating. The analysis of the results allows correct and reliable design of dowel fastenings and opens up new questions that require additional research.

One of the areas of sustainable construction with realization the Zero waste concept is the utilization and reuse of industrial waste, in particular used rubber tires, in concrete. When adding crumb rubber, a decrease in the strength of cement-based materials is observed. In order to increase strength, Portland cement was modified with a complex additive based on polycarboxylate superplasticizer and microsilica, and the influence of rubber crumb on the properties of modified Portland cement systems was studied. The use of the optimal amount of microsilica in the rubberized Portland cement system with a superplasticizer provides an increase in early strength by 33.6%, and strength after 28 days by 8.4% compared to system without crumb rubber. Samples of Portland cement systems containing rubber show elastic behaviour under dynamic loading. They are destroyed slowly after the appearance of cracks and characterized by additional resistance to loads after reaching the breaking stress. Impact resistance of rubberized modified Portland cement systems increases by 2.0–2.7 times compared to system without crumb rubber.

The article is devoted to one of the most promising types of cement concrete, Earth-Moist Concrete (EMC) and its variety Roller Compacted Concrete (RCC), which were and are used in the manufacture of slabs, building blocks, as well as in the construction of dams, and road foundations and рavements. It has been shown that EMC and RCC have higher quality indicators than traditional types of cement concrete. To increase the efficiency of using EMC technologies and reduce costs, it is advisable to introduce waste and by-products of various industries into their composition. The article presents for the first time the results of studies of the influence of concrete mixture components on the elastic modulus and strength of EMC products. The research carried out will make it possible to improve the deformability of road foundations and рavements made of RCC already at the design stage of the compositions, as well as to increase the durability of products and structures made of EMC.

A new method of cooling outdoor air in ventilation systems of poultry houses is proposed, which is based on the use of water from underground wells and heat exchangers of recuperators for cooling supply air.Numerical modeling of aerodynamics and heat transfer processes in poultry houses with a tunnel ventilation system was carried out. As a result of numerical calculations, the distribution of temperatures, velocities and pressures in the air environment of the poultry house was obtained. The use of heat exchangers to cool the supply air makes it possible to maintain its temperature at + 20–25 ℃ and reduce the moisture content in poultry rooms, which are high when using cassette methods or spraying water with nozzles to cool the supply air.As a result of the conducted numerical studies, it is recommended to increase the air flow due to the inclusion of the third exhaust fan, which is located on the upper line of the rear end wall. This will make it possible to obtain a more uniform temperature distribution in the poultry house.

This article presents a model for assessing the reliability of RC beams strengthened under load using Monte Carlo simulation (MCS). To develop a model, the real-operating conditions of the considered members were simulated. The model takes into account such stochastic parameters: the strength of materials, external loads, geometric dimensions, and the current load level during strengthening and it was implemented by PTC Mathcad Prime 6.0.0.0 software package. The proposed model was tested on the experimental data from previous studies of strengthened in stretched zone RC beams. The reliability parameters for a row of samples were obtained – reliability index β and failure probability P(β). Analysis, which included an assessment of the effect of accepted input random variables on the above reliability parameters of structures was also made. After implementing the developed algorithm in the PTC Mathcad Prime environ-ment, the effect of input parameters on the reliability index and the failure probabil-ity of strengthened beams was analyzed. In addition, for increasing the accuracy of the assessment the failure probability and the reliability index, a proportional increase in the sample is advisable.

The results of the calculation estimation of the energy expenditure in different ways of water lifting in a geothermal circulating system are presented. The increase in the efficiency of air-lift technique as compared with pumping operation methods is demonstrated. Reservoir pressure and well production rate are decreased under the condition of the prolonged operation period of a geothermal field. Wells are transferred from the gushing forth mode into the pump operation one; later on the portion of pressure wells, and in the final operation period all pressure wells are transferred into the operational well mode. To increase the operational efficiency of a geothermal field the transfer from the extensive gushing technology to the intensive circulating one is required with the increase in the operational-well output by 2–4 times by means of the forced lifting of geothermal water and lowering the heat production cost by 1.3–1.8 times. The results of computer modeling were compared with the data from experimental measurement. The obtained results indicate the possibility of practical application of airlift technology to reduce energy costs in geothermal circulatory systems.

Urban Heat Islands (UHI) is a consequence of urbanization and increased heat absorption, leading to local temperature rises in urban areas. This phenomenon is exacerbated by climate change, which brings frequent weather fluctuations – intense heat waves and heavy precipitation within short periods. Green roofs represent one solution for mitigating the UHI effect, thanks to their water retention capacity and gradual evaporation, which creates a cooling effect on the building and its surroundings. Recently, a new variant of the green roof has appeared, the wetland roof. Such roof is expected to be equally advantageous as green roofs and, in some cases, even more so due to the permanent presence of water and the use of wetland plants. In May 2022, an experimental wetland roof was constructed next to the existing experimental green roof, to verify the interaction of such roof type throughout the year. The article focuses on the temperature fluctuation in selected layers of the green and wetland roof. The first results from the roof monitoring are presented. Comparing these elements contributes to a better understanding of the impact on the building and the composition of the roof.

Climate change has led to the temperature rising, the river flow decreasing during the summer months, and to the flood frequency increasing up to ten times a year in the mountainous Carpathian region. Reducing the harmful effects of droughts and extreme floods has become a pressing issue today. It is possible to increase the water levels in the dry season and to replenish floodplain areas (green-blue islands) in urban areas by creating the backwater in the riverbed. The purpose of the work is to assess the water replenish possibilities of the blue-green zone, taking into account the extreme flood to improve the management of water resources on the urban area. Simulations were carried out with the backwater creation by flap gate, weir and riffles and their impact on the extreme flood levels and a spring seasonal flood during the mean year was estimated for the central part of the city. The calculations showed a negligible effect of the backwater structures on the rise of the water level during the extreme flood. The ability to operate the flap gate with dropping down to the foundation let to maintenance the constant water level during the spring flood.

The integration of green building technologies is revolutionizing the construction industry and urban development. These technologies are not only environmentally friendly but also economically beneficial, as they lead to energy savings and reduced resource consumption. The adoption of sustainable design principles, renewable energy sources, and strict environmental regulations is reshaping the skill set needed in the construction workforce. Education and training programs are essential to equip professionals with the expertise to implement these green building methodologies effectively. As the industry evolves, the impact of technological advancements on professions within green buildings is profound, necessitating a workforce that is proficient in energy efficiency, water conservation, and the use of sustainable materials. This transformation is pivotal for creating a more sustainable future, where buildings contribute positively to the environment and society. The focus on green skills development is a critical step towards meeting the growing demand for sustainable construction practices and ensuring that the workforce is ready to meet the challenges of tomorrow’s green economy. In Slovakia, there remains immense potential for the implementation of green concepts in the realm of existing residential and public buildings. This potential extends to related education at universities and the establishment of vocational centers of excellence.

Modern design trends are very different from those of 20 years ago. Complex architectural forms, free planning, individual heating, ventilation and smoke removal systems… All this affects the supporting frame of the building - additional openings, equipment and irregular pitch of columns, increased spans and consoles. All these factors especially affect floor slabs, which are often provided without beams and capitals or only with local reinforcements in certain places. Therefore, it was decided to carry out field tests to establish their strength and deformability. The tests consisted in loading fragments of floor slabs according to previously developed schemes. The total load was approximately equal to that which will be during the operation of the building. The entire experiment was simulated in a computer program LIRA-FEM to control and analyze the data while it was carried out at different loading levels.Based on the obtained results, technical instructions and regulatory documents, recommendations were developed: for the calculation of structural schemes taking into account the non-linear nature of the work of materials; location of technological holes for engineering networks; reinforcement with longitudinal reinforcement; deflection.