Vol. 5 Issue 2

Archives Journal Construction Materials and Products 2021

DEVELOPMENT OF A MULTICOMPONENT GYPSUM CEMENT BINDER USING THE METHOD OF MATHEMATICAL PLANNING OF THE EXPERIMENT

https://doi.org/10.34031/2618-7183-2022-5-2-5-12
Abstract
In the article, using the method of mathematical planning of the experiment, the influence of formula and technological factors on the properties of hardened multicomponent gypsum-cement binders with a mineral additive finely ground to a specific surface of 300-700 m2/kg of quartz sandstone crushing screening (QSS) JSC Lebedinsky Mining and Processing Industrial Complex, Gubkin, Belgorod region, Russia was determined.
It has been established that the use of finely ground QSS as part of a gypsum cement binder with a ce-ment/QSS– 1/2 ratio contributes to ensuring its operational characteristics and stability of properties during solidification at the required level, contributing to a decrease in the concentration of CaO in the liquid phase of the hardening system.
The optimization task was to determine the conditions for the preparation of a gypsum-cement mixture with a movement of ≤ 120 mm (according to Suttord) and the beginning of the setting time of ≥ 6 min, with the provision of the maximum compressive strength of the hardened binder. An active 3-factor experiment was planned. The following were studied: the compressive strength of hardened gypsum-cement binder samples in 2 hours of hardening – Rcomp2(Y1); at 28 days of age – Rcomp28(Y2); as well as the mobility of the gypsum–cement mixture – P (Y3) and the timing of the beginning of setting - T (Y4). With the help of mathematical processing of the results of experimental studies, regression equations were obtained and with the help of nomograms constructed on the basis of mathematical expressions, the rational compositions of gypsum cement compositions were graphically and analytically determined.
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ALTERNATIVE METHOD OF EXPERIMENTAL MEASUREMENT OF THE ANGLE OF DEFLECTION FROM VERTICALITY OF THE FRAME IN DESIGN AND CONSTRUCTION

https://doi.org/10.34031/2618-7183-2022-5-2-13-21
Abstract
The design of high-rise complexes includes the solution of a multifactorial problem, consisting of: survey work (geodesic development; tracing work; marking and survey work; engineering-geological, hydrogeo-logical, hydrological), functional operational, as well as the reliability of the structure, the prospects for its further reconstruction, economic feasibility of construction, selection of structural components of the object, etc. The purpose of this work is theoretical and experimental research in the design and construction of facilities, including alternative methods for measuring the angle of deviation from the vertical frame of a structure (during the frame erection of structures).
To determine the deviation of columns from verticality, an alternative method is proposed for "indirect measurements of the angle" of the deviation of the column, as well as the distance from the theodolite (total station) to the plane of the standard. Geometric schemes for determining the linear angle of deviation of a column from verticality and the installation of a theodolite (tacheometer) for recording deviations of columns perpendicular to the sides of the structure are presented.
The technique of carrying out experimental researches is described and the received graphic dependences are resulted. The performed surveys and calculations make it possible to determine the deviations of the columns from the vertical by means of angular measurements from the ground.
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COMPROMISE INTERACTION OF TRANSPORT AND PEDESTRIAN FLOWS ON THE EXAMPLE OF RENOVATION PROJECT OF THE STATION SQUARE IN YUZHNO-SAKHALINSK

https://doi.org/10.34031/2618-7183-2022-5-2-22-34
Abstract
City squares have historically been a place of attraction for people. Since the development of large cities, squares have become a socio-cultural part of the urban space, embodying a place of recreation, communica-tion, trade and leisure for city residents. In today's urbanized environment, it becomes very important to solve transport problems and individual, recognizable filling.
The article explores such a type of urban space as the square in front of the railway station. Modern requirements and approaches are considered from the point of view of functional division, transport solution, security for all users, information component, recreational potential and figurative solution. On the example of analogues, an analysis of the trends that have developed in recent years in the design of railway station areas has been carried out, and the main techniques that are most suitable for use in the city of Yuzhno-Sakhalinsk have been identified.
The final part of the article is devoted to the analysis and project proposal for the renovation of the station square in Yuzhno-Sakhalinsk. As a result of the transformations, the square should receive a clear functional division, become the center of architectural and landscape transformations, a point of attraction for citizens, a place of safe transit, recreation and leisure for residents.
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RESEARCH OF THE RESPONSE SURFACE OF THE INTEGRAL POTENTIAL OF CAPITAL REPAIRS AND RECONSTRUCTION OF PUBLIC BUILDINGS IN THE FUZZY INFERENCE SYSTEM

https://doi.org/10.34031/2618-7183-2022-5-2-35-42
Abstract
It is proposed to use fuzzy production rules when making decisions on inclusion in the title list of public buildings, since in the practice of assessing the technical condition of a building on the basis of an expert opinion based on the results of a survey, the duration of operation determined in accordance with regulatory values, deadlines for work and other indicators affecting the integral potential of including a building in the capital repair and reconstruction plan, such fuzzy concepts as "satisfactory", "unsatisfactory" and others appear. The article proposes the use of the original fuzzy inference methodica to assess the need for major repairs and reconstruction based on the potential of organizational-technological solutions and analyzes the response surfaces, that is, the values of the integral potential depending on expert assessments of input factors.
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TEST OF HEAT PUMP UNIT WITH MOVEBIT ANTI-ICING SYSTEM

https://doi.org/10.34031/2618-7183-2022-5-2-43-50
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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