Introduction: Beam is one of the most common wooden structures. The use of beam structures is relevant in the flooring and roofing of buildings. A disadvantage of using wooden beams is the impossibility to cover a span of more than 6 m without expensive factory-made structures (glued beams, composite beams, metal-and-wood beams, LVL beams, etc.). The study proposes a wooden structure of a composite girder truss with a span of 9 m, assembled from planks with the use of steel dowels directly at the construction site. The purpose of the study was to experimentally determine the strength and deformability of wooden girder trusses with a span of 9 m. The following methods were used: experimental investigations of the stress-strain state of beams. As a result, brittle fracture was noted in the area of the support chord junction with the span chords under the action of breaking load equal to 14.52 kN/m. The values of tensile and compressive strength of wooden girder trusses were experimentally determined to be 35.35 MPa and 25.14 MPa, respectively. The developed wooden girder trusses are recommended for use in the flooring of buildings with a span of 9 m.

Introduction: The study of the adhesive strength formation mechanisms in polymer composites involves the deliberate selection of components to facilitate their joint action in transferring stresses from the fibers to the binder through the phase interface. The strength of the adhesive interaction between components can be expressed through their energy characteristics, provided technological and other factors are ensured. Purpose of the study: The study aims to investigate the energy characteristics of hybrid polymer composite phases at the air interface. Methods: The optical method was used to capture micrographs of wetting fibers of different nature by liquids, based on which contact angles were determined. Tensile tests of fibers were conducted, and thermal analysis of fibers was performed using a synchronous thermal analyzer. The surface tension of epoxy resin and the epoxy resin / hardener system was determined using a tensiometer. Results: The method for determining surface energies of solids was upgraded. The upgraded method makes it possible to determine the free surface energy of fibers of different nature and the surface tension of the binder. The effect of oiling compositions (finishing agents) was quantitatively evaluated.

Introduction: The region of Dakshina Kosala (also known as South Kosala) is mentioned in various ancient Indian texts. The exact geographical boundary has continuously changed over time, and today, only a rough estimate can be made of the Dakshina Kosala region, which approximately covers the northern and central parts of the present-day state of Chhattisgarh, along with the western part of the state of Odisha, India. Excavations and writings show that this was a prosperous region near central India, without any seaport, but with large markets, trade centers, and educational institutions. To access this region, many trade routes were established from various parts of India. This led to the development of cities with markets along these trade routes. Many temples were also seen in this region, serving as examples of the intangible heritage of the place. Purpose of the study: This region made a significant contribution to the temple art and architecture of India. The present study aims to determine if there is a spatial and architectural link between the temples in this region. Methods: The methodology involved an initial phase of reading and analyzing pertinent literature to prepare detailed maps delineating the boundaries of Dakshina Kosala. Subsequently, employing rigorous analysis with Google Earth and GIS tools, ancient trade routes were traced, temples were located on the maps, and a comprehensive analysis was conducted to derive conclusive results. Results: This paper establishes a relationship between the geographical locations and construction materials of the temples within and outside the geographical boundary of Dakshina Kosala.

Introduction: The purpose of the work is to study the processes of snow transfer and snow deposition on the roofing of a unique building. Currently, the problem of assigning snow loads to the roofs of buildings and structures remains relevant, since cases of roof collapses in winter are still recorded annually, including those in the Russian Federation. A circus building with the roof in the form of a suspended reinforced concrete shell was chosen as the object of study. Methods: The design diagram for this type of roof is contained in SP 20.13330.2016; the snow load distribution diagrams for this roof were adopted according to Appendix B to SP 20.13330.2016. The author considered several options of snow load distribution and chose the most unfavorable one, when an increased value of the snow load is observed on one half of the roofing. During one winter period, field measurements of the thickness of the snow cover were carried out at the site. Results:It was established that in general, with the exception of local zones, the actual distribution of snow cover coincides with the adopted design solution, while the actual value of the weight of the snow cover for the current winter season was significantly lower than the calculated one. Discussion: The obtained result demonstrates that when developing design solutions for certain types of suspended roofing, it is permissible, without conducting specialized experimental studies, to use the data given in the scientific and technical literature, based on the results of monitoring the thickness of the snow cover on the roofing of the building.

Introduction: Searching for methods to improve the efficiency of water treatment with reagents is quite important in both water conditioning and industrial wastewater purification. Among the technologies providing high efficiency and reducing resource consumption in combination with reagent methods, hydrodynamic cavitation water treatment is of particular interest. The analysis of scientific and technical data made it possible to determine the main indicators of hydrodynamic cavitation water treatment that can affect the efficiency of reagent purification. Extreme parameters occurring during intense cavitation are associated with the formation of high temperatures up to 2000°C and high pulse pressures of 100–1500 MPa in local areas of hydrodynamic systems. In such conditions, the initiation and intensification of the physical and chemical processes of water treatment are observed. Рurpose of the study: Improving the efficiency of existing traditional water purification technologies, allowing to improve its quality at the lowest cost. Methods: To study the parameters affecting water treatment efficiency and occurring with the cavitation flow of water, simulation in Ansys CFX was performed with the use of the finite volume method. The calculation was carried out with account for the turbulent nature of the flow based on the k-ε turbulence model. The cavitation process was calculated with the use of the Rayleigh-Plesset cavitation model. Results: Steam formation in the cavitation reactor promotes sufficiently complete absorption of the gaseous disinfectant by water. An increase in temperature is also considered as one of the factors increasing the efficiency of water treatment with reagents. During cavitation, water temperature increases in local micro-volumes. Thus, to intensify the process, there is no need to heat the entire volume of liquid, and, as a result, the total energy consumption for water treatment is reduced.

Introduction: With the rapid development in computational design, both architectural design and representation processes have witnessed a revolutionary change from the analog to the digital medium, opening new doors for adaptability in the architectural design process by leveraging nature concepts in design. The computational design approach starts with the mathematical model definition based on numerical relations and equations, thus, replacing the standard visual representation. Purpose of the study: We aimed to integrate computational design technologies to create self-learning buildings that could adapt to environmental challenges and adjust accordingly by collecting data from the surrounding environment via the implementation of sensors. Methods: We started with extensive research on state-of-the-art computational design in architecture, followed by the design implementation and the implementation of the architectural design of a building. The design followed a parametric approach to design and strategies. An algorithm was developed with Grasshopper Scripting to generate documents that mimic the growth process of cellular bone structures and adapt that form to a selected project site. To ensure that the generated form is adaptable, we performed multiple analyses, such as sunlight, radiation, and shadow analysis, before selecting the form and finishing its development. The results show that an environmentally responsive form that extends from the surrounding environment is characterized by high levels of adaptability. Results: In the course of the study, the effectiveness of computational design technologies in architecture was established.

Introduction: In this paper, we consider LVL (laminated veneer lumber with unidirectional veneer) as an element of plane trusses and geodesic domes, acting as the bearing structure of roofs, and study destruction of LVL joints, which is necessary to improve designs of wooden roofs under consideration. Methods: Our studies were based on structural mechanics and wood science. In the course of the study, we used analytical, experimental, and statistical methods to process the results of tests. Results: Based on the experimental studies performed, we suggest a method to determine the design bearing capacity of treenails per edge joint (conventional shear) for joints of LVL elements with wood laminate (DSP-V, wood laminate where veneer fibers in the adjacent layers are mutually perpendicular) plates. Discussion: We obtained new values of the coefficient taking into account the compliance of connections for nodes and joints in LVL composite elements, which make it possible to quickly determine the required cross-sections of bearing rod elements in plane trusses.

Introduction: Fresh water suitable for water supply has been depleted due to production activities. Thus, closed water supply cycles are required at civil infrastructure facilities. The quality of water must meet the requirements on its use for various purposes. It is common knowledge that water is essential in providing adequate health and sanitary conditions for the public. Therefore, issues of water treatment remain in the focus of researchers. Water disinfection is one of the mandatory methods used in water purification and treatment. Currently, chlorination is still the main technology for water disinfection. However, it is responsible for toxic, carcinogenic, and other types of negative effects on the human body. In this paper, we consider the use of oligodynamic solutions as a new, rapidly-developing direction in water treatment. In the course of our study, we addressed a method of swimming pool water disinfection using units of oligodynamic synthesis and examined the results of treated water quality analyses. Methods: The study was based on the statistical analysis of water quality indicators in pools with water treated with silver and copper ions. The analysis made it possible to determine the hygienic safety and reliability of products. To assess hygienic safety and reliability, we analyzed the composition and properties of the product (oligodynamic solution) as well as the composition and concentration of impurities in pool water and determined if the disinfecting properties of water are preserved and proper levels of copper and silver ions (not exceeding MAC) in pool water are maintained. Results: The paper provides a rationale for procedures to analyze and determine the safety and reliability of small-scale units producing disinfection solutions to ensure optimal swimming conditions in swimming pools. Discussion: The obtained results indicate that it is expedient to apply oligodynamic water treatment to ensure the hygienic safety and reliability of swimming pools. The technology suggested fully meets the requirements of sanitary regulations on water quality.

Introduction: This paper studies the frequency with which hydrodynamic parameters change in the sudden expansion section of axisymmetric pressure flow, based on the boundary layer equations. Methods: The suggested method reveals the regularity of changes in the hydrodynamic parameters of the flow in the transitional area, making it possible to obtain a velocity profile in any cross-section under common initial and boundary conditions. Based on the general solutions, we studied the hydrodynamic processes occurring in the transitional area of the effective sudden cross-section expansion within the axisymmetric pressure movement, in the following cases: a) when the velocity is constant at any point of the inlet face; b) when the velocity is distributed along the inlet face according to the parabolic law. Our calculations were carried out for different values of the expansion factor. Results: Based on the results of the computer-aided experimental study, we obtained velocity diagrams along the length of the transitional area with constant and parabolic velocity distributions for fluid inflowing into the expanded section. We also determined the patterns of pressure distribution along the length of the relevant section.

Introduction: The rate of urbanization is currently high. Therefore, it is important to use various elements and devices for water intake and water supply. Purpose of the study: We aimed to consider and analyze the structural features of a water intake facility for mountain and submountain rivers. Methods: In the course of the study, we used the synergistic research principle and statistical analysis. We analyzed the types of water supply networks at mountain rivers and identified the features of water intakes at water sources of this type. Results: A description of water intake features under flood conditions in the Amur Region, exemplified by the Bureya River, was obtained. The mountain rivers have an uneven runoff, which fluctuates not only throughout the year but also throughout the day. The water supply of the mountain and submountain areas shapes the idea of hydrological control over the regime of the mountain rivers. This paper will help to study changes in the average water inflow over the years and thus facilitate an accurate and detailed description of the water inflow characteristics in the Bureya reservoir when planning the water-energy modes of the hydroelectric power plant.