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2022

Archives Journal Construction Materials and Products Vol. 5

TEST OF HEAT PUMP UNIT WITH MOVEBIT ANTI-ICING SYSTEM

https://doi.org/10.58224/2618-7183-2022-5-2-43-50
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 43-50 p.
Abstract
Use of heat pump units is one of the directions for introducing energy-saving technologies into engineering systems. Air heat pumps are more promising than geothermal ones, but their use in cold climates is limited by formation of frost on the evaporator heat exchanger. This paper presents a heat pump unit with a system for breaking ice with using oscillatory circuits. The air heat pump unit with MOVEBIT anti-icing system, including the oscillatory circuit, has been developed. It was tested in the temperature range from -26 up to +10 . The transformer ratio is determined as the ratio of the heat received to the operation expended. The calculation of heat output was carried out using a computer program that includes the flow main parameters. The calculated and experimental values of the coefficients are compared. Studies have shown that a change in the temperature of the air entering the evaporator of the pumping unit with the anti-icing system does not significantly affect the energy efficiency of the equipment under test. The MOVEBIT outdoor air heat pump allows to obtain a conversion factor in the range of 4-6 when operating in areas with outdoor temperatures down to -27 and can compete with geothermal heat pumps. Measurements of the sound impact of the anti-icing system showed the need to reduce it by 30 %.
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THE RELIABILITY COEFFICIENT FOR FIBRE CONCRETE MATERIAL

https://doi.org/10.58224/2618-7183-2022-5-2-51-58
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 51-58 p.
Abstract
One of the main parameters of the method for calculating building structures made of concrete and fibre concrete by limiting states is the reliability coefficient for the material, which characterizes the heterogeneity of the physical and mechanical properties of the material. In national and foreign standards, it takes a constant value of 1.3 (obtained on the basis of direct tests), or 1.5 (obtained on the basis of indirect tests and the use of graduated dependencies). The concrete matrix for the formation of the structure of fibre concrete is most often fine-grained concrete with special additives, which has greater uniformity in comparison with heavy concrete, which cannot but affect the reliability of the composite material in question as a whole: the stock coefficients for fibre concrete should be lower than for normal concrete, which has not been reflected in modern standards for design yet. Starting from interval estimates of the average strength value, a new approach to determining the reliability coefficient for the material, differentiated by the 1st and 2nd groups of limit states, is proposed. The results of calculations according to the proposed formulas for previously conducted tests of steel- and glass-fiber concrete images allowed us to conclude: the introduction of fiber into the concrete matrix of the proposed effective composite composition increases the uniformity of the strength properties of the material, which leads to an increase in the reliability of its use in building structures, a decrease in the value of the reliability coefficient (margin) for the material to 1.164...1.235 for central axial compression and up to 1.172...1.272 – for central axial stretching. The obtained actual coefficients in strength calculations will allow to reveal the supplemented reserves of the bearing capacity of structures made of this material up to 22.4%.
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THE PRACTICE OF USING TECHNICAL FABRICS IN THE PRODUCTION OF HEAT-RESISTANT SLEEVES

https://doi.org/10.34031/2618-7183-2022-5-1-5-14
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 5-14 p.
Abstract
The article has developed and mastered promising technologies for the production of heat-resistant metallurgical hoses, which include the use of synthetic materials for the power frame and fire-resistant - cover fibrous materials. Experimental studies have been carried out to reduce the material consumption of the production of sleeves, due to changes in manufacturing technology at the stage of cutting the strips of the power frame and assembling the sleeves. A sleeve manufacturing technology is described, which provides for the introduction of a wire spiral into the sleeve design to protect the sleeves from loss of transverse stability and reduce the bending radius. Technical cord materials for the manufacture of a power frame for sleeves of various types in production are considered. The technology of protecting the outer surface has been mastered, providing for the creation of bumpers of various design schemes. In order to increase the temperature resistance of the operation of metallurgical heat-resistant sleeves, a technology has been created for the manufacture of sleeves based on non-flammable and fire-resistant fabric materials covering the sleeves on the outer surface. The operation of the hoses showed the correctness of the developed technologies and the choice of appropriate materials. Research work on the development of new fire-resistant materials for heat-resistant hoses has been carried out. The prospects of using innovative technology for manufacturing heat-resistant metallurgical hoses are noted.
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FUNCTIONAL AND STRUCTURAL CONNECTIONS IN THE ARCHITECTURE OF MODERN INDUSTRIAL BUILDINGS

https://doi.org/10.34031/2618-7183-2022-5-1-15-37
 15-37 p.
Abstract
Today, up to 80% of buildings and structures are built on deep foundations, the main elements of which are concrete and reinforced concrete piles (hammered, bored and piles made according to CFA technology). Since the beginning of the mass use of drilling piles (the 60s of the last century), there is still a problem of ensuring the reliability of foundations, due to the fact that the process of installing piles is hidden from observation, and unacceptable defects may form in the pile trunks, which reduce the bearing capacity of piles and can lead the structure to an emergency condition. Pile construction technologies are constantly being improved, however, it is still not possible to avoid the appearance of defects in pile trunks because there are quite a lot of reasons for the formation of defects that it is not always possible to foresee and take into account. That is why, during the construction of deep foundations, output monitoring of the technical condition of drill pile shafts should be provided, which cannot be performed without the use of non-destructive diagnostic methods. The use of these methods and means, which implements them, should be mandatory to ensure the reliability and safety of the operation of buildings and structures and today is already provided for by numerous standards and regulatory documents. Currently, acoustic methods are mainly used for diagnostics, namely: single- and multi-channel acoustic logging; pulse Echo method with shock excitation of elastic waves (hereinafter referred to as the method of vibration-shock diagnostics). It should be noted that in the case of using high deformation to excite elastic waves, at which the impact energy on the end of the pile reaches the limit of proportionality, an assessment of the bearing capacity of experimental piles is given, and the low technique is used exclusively for diagnosing pile trunks. For a long time, these methods could not be widely implemented in the field. Their capabilities have increased significantly after the development of digital signal processing methods.
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MODULAR STRUCTURES AS A METHOD OF ARCHITECTURAL ENVIRONMENT ARRANGEMENT

https://doi.org/10.34031/2618-7183-2022-5-1-38-53
 38-53 p.
Abstract
Key versions of the concept «module» in the sphere of architectural design are considered. Modular structures are defined as a means of creating a flexible and dynamic architectural environment with variable functional parameters, the main potential of which is expressed in the speed of erection, autonomy, economical efficiency, transformative possibilities. The main features and advantages of the modular structures as well as the most effective fields of their application are considered. Examples are given of modular objects from current construction practices that illustrate the possibilities and specific means of their formation. Special emphasis has been placed on the ecological feasibility of modular facilities, as well as on the possibility of their interaction with the established architectural context. The use of the modular method in extreme conditions, including the formation of a habitable environment in outer space, is considered.
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FEATURES OF DEVELOPING UNIQUE ARCHITECTURAL SOLUTIONS USING DIGITAL METHODS BASED ON VISUAL PROGRAMMING

https://doi.org/10.34031/2618-7183-2022-5-1-54-59
 54-59 p.
Abstract
The article deals with the creation of a parametric facade by writing an algorithm based on attractor modeling methods. The article analyzes various options for extracting facade solutions based on world and domestic design experience. In addition, the article describes in detail the general algorithm for creating a parametric facade using the Rhinoceros program and the Grasshopper component environment. Architecture combined with modern digital technologies can provide an opportunity for the emergence of a new type of architectural thinking both in the context of shaping and in the context of design. Today, the architectural world is constantly replenished with new innovative tools and the design methods generated by them, but until now there was no clear classification and structuring of emerging opportunities. At the early stages of the emergence of digital methods, it is important to create a hierarchy of all tools and understand which one is suitable for certain tasks, create a base of experiments and results based on the latest methods. This approach finds its relevance in modern methods of architectural design, as it provides an alternative choice of options and a high speed of automated modeling.
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