bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis of high alumina cement based on metallurgy wastes
Authors: Krivoborodov Yu , Samchenko S
Published: December 2019

In this paper efficient types of binders – high alumina cements are considered. The shortage of industrial alumina and its high cost constrain the development of high-aluminate cements production. Waste from a number of metallurgical industries can be used as raw materials for their production. The aim of the investigation was to study the influence of metallurgical waste on the mineral formation of aluminate clinker and the properties of cement based on it. As a replacement of industrial alumina, dust of gas cleaning plants of aluminum electrolysis and slag of ferroalloys production were used. Aluminate clinkers were obtained in a laboratory furnace at a temperature of 1200-14000 °C. Mineral composition of clinkers was studied using chemical analysis, XRD and optical microscopy. The cements were obtained by grinding clinkers in a laboratory mill, then they tested for strength at the age of 28 days. It was established that the chemical and phase composition of dust allows to use it as a raw component in the production of high alumina cement. The investigations showed that the properties of alumina cement based on slag ferrovanadium production improved. Hydration activity of cement increases especially in the early period of its hydration.
Determining service life of non-ballast track based on calculation and test
Authors: Savin A V , Korolev V V , Shishkina I V
Published: December 2019

At the Test Loop of JSC VNIIZHT there have been finished unique testing of non-ballast track in a volume 1.1 milliard tones gross of passed tonnage. The calculation-test method for service life definition of non-ballast track at high-speed track is presented under test results on the Test Loop. Taking into account operation conditions at the high-speed track 176.6 kN on axle the speed is 300 km/h and working capacity is 30 mln. t gross, the passed tonnage will make up 2270.4 mln. t. gross or 75.7 years of service. The authors developed a calculation-test method, which allows predicting for a good reason a service life of innovate track construction upon the calculation and accelerated test results on a closed polygon. The article provides a way to forecast the behaviour of various track constructions in advanced operation conditions that are not yet created according to the results of tests on the Test Loop. The reasonably calculated service life of a non-ballast track makes it possible to objectively compare it with the payback period, thus determining the expediency of its construction at the testing stage.
Calculation of road clothes by elastic deflection criteria taking into account damage to asphalt concrete
Authors: Chusov V V , Aleksandrova N P , Ignatov V F
Published: December 2019

In the article the analysis of methods of calculating non-rigid road pavements according to the criterion of elastic deflection. The possibility of using different solutions (Burmister, Korsunsky, Ivanov, etc.) to calculate the deflection of layers of monolithic and granular materials is evaluated. Based on this analysis, the formulas for calculating the equivalent modulus of elasticity of a two-layer system, the upper layer of which is made of monolithic or granular material, are recommended. The authors made the modification of formulas for calculating the deflection of asphalt concrete layers and the equivalent modulus of elasticity on their surface. The modification was made by introducing into the calculated dependences a scalar quantity, called damage. To calculate the damage, the principle of equivalence of deformations is recommended, in which the damage is determined using the relations of elastic modules of the damaged and solid body. To calculate the elastic modulus of the damaged body, a functional dependence on the number of loads was obtained.
Combined roasting of raw materials modified by additives-intensifiers in form of low humidity sludge
Authors: Averina G F , Koshelev V A , Kramar L Y
Published: December 2019

This article describes the method of obtaining magnesium oxychloride cement for construction purposes. The study describes the possibility of introducing additives that intensify the process of burning magnesium-containing raw materials in the form of an aqueous solution to obtain a sludge of low humidity. The advantages of this method are described in comparison with the known method of wet granulation of ground raw material with an aqueous solution of the additive. A two-factor experiment was carried out to identify the optimal grain size of the raw material. The dependences of the change in the strength characteristics of a magnesium stone on the amount of the intensifier additive and the fractional composition of the modified raw material are described. The optimal area of the applied fraction and the amount of the additive, allowing one to obtain a magnesium stone with maximum compressive strength, has been established. The authors investigate the tendency of all samples to the formation of cracks. The reasons for the use of grain size outside the established range negatively affecting the quality of the magnesium oxychloride cement obtained are suggested.
Study of high-strength steel fiber concrete strength characteristics under elevated temperatures using mathematical modelling methods
Authors: Konopatskiy E V , Mashtaler S N , Bezditnyi A A
Published: December 2019

This article presents the study of the various factors influence on the high-strength steel fiber concrete strength characteristics using a mathematical model that was obtained on the basis of experimental data. At the same time, the steel-fiber concrete reinforcement, the scale factor, the temperature and the duration of heating are related to the factors under study. A fundamental approach to building a model is to use exponential functions. This function allows to move from the product of the studied factors to their sum, which greatly simplifies the further use of the dependencies obtained in engineering practice. Separately, it should be noted that one of the studied factors (the duration of exposure to temperatures) is set by the result of its impact on the final response function. That is, taking into account the destructive processes in the structure of concrete with short-term heating and structural – with long-term. In addition, the optimization of the proposed mathematical model is performed, as a result of which it is established that the maximum values of the strength of the steel fiber concrete is achieved at the values of the percentage of reinforcement of HSFRC.
Application of oil-products-containing water treatment sludge in wall ceramics production
Authors: Starostina I V , Shevtsova R G , Starostina Yu L
Published: December 2019

The article presents the research findings concerning the usage of carbon-containing water treatment sludge of test solutions, containing emulsified oil products, in raw charge for wall ceramics production. For removing oil products kieselghur sludge was used, generated at the refined vegetable oil production at winterization stage (removing waxes and waxlike substances), thermally modified at temperature 450°C. Water treatment sludge is characterized with organo-mineral composition. It was determined that baking ceramic samples with water treatment sludge at temperature 950°C causes the oxidation of oil products with the formation of gaseous products CO, H2O and CO2, which makes ceramic materials’ structure porous, which in its turn reduces their density and improves their heating-performance characteristics. The presence of organic substances in the charge for ceramic materials creates favorable thermodynamic conditions for iron oxides reducing reactions, which contribute to the formation of low-temperature silicate melt and intensify the samples’ baking process. The wall ceramics products, obtained with the use of water treatment sludge, can be used as construction material and heat-insulating material in enclosing structures and at internal partitions installation.
Computer simulation of special tomographic defectoscopy
Authors: Zerkal S M , Kislenko N P , Kornatskiy V Yu
Published: December 2019

The paper proposes an algorithm for the reconstruction of the defect of the product on the basis of non-destructive testing, based on the use of a reference sample of the studied object. It solves the two-dimensional problem of industrial tomography, which consists in the restoration of the image of the defect based on the use of a reference sample. Assuming that inside the object there is a defect of a flat elongated structure, the width of which is much smaller than the diameter of the object, it becomes possible to implement a fairly economical algorithm for defect reconstruction, taking into account only those elements of the projection matrix that correspond to the rays, which significantly pass through the defect.
Modifying non-autoclaved foamed concrete technology on the magnesia cement with crystal starter seed infusion
Authors: Averina G F , Zhivtcova R A , Kovaleva O I
Published: December 2019

The article deals with the capability of non-autoclaved foamed concrete quality improvement by entrained mixture additives infusion into structure, which are the active centres of the basic phases magnesia stone crystal yielding. Two factor experiment of optimal concentration proportioning was conducted and finished by plotting graphic diagrams. The paper studies the basic mechanical characteristics of designed foamed concrete while conducting the experiment. We revealed a positive effect of crystallizing centres infusion on the speed of taking bearing power and resistance of modifying mixture. The paper studies the phase structure of hardened magnesia stone and determined the effect of the basic structure-forming minerals composition on the strength characteristics of foamed concrete on its foundation, along with the exploitation samples characteristics of optimized composition.
Wall panels for agricultural and industrial buildings
Authors: Gorin N I , Ryabchun S A , Kulik O G
Published: December 2019

The authors develop a new construction, manufacturing technology and method of calculating three-layer wall panels with heat-insulating packages embedded in a contour frame of lightweight concrete for agricultural and industrial buildings. The proposed technical solution gives the wall panels a number of significant distinguishing properties: the outer and inner plates of the heat-insulating package of the panel along the contour are embedded in the monolithic reinforced concrete frame; a layer of insulation is embedded in the contour frame, which ensures a decrease in its thermal conductivity; embedding of plates and insulation in the contour frame minimizes the labor capacity of the elements connection; placing a layer of insulation between two pre-made plates.
Study of strength characteristics of earthen cloth of roads in south of Russia
Authors: Aleksikov S V , Leskin A I , Gofman D I
Published: December 2019

The influence of humidity and density of clay soil on its strength characteristics is studied in this paper. It is proved that increase in density of a roadbed allows one to increase bearing capacity of the soil basis and reduce thickness of road designs. The effective solution of increase in reliability of roadbed and decrease in its thickness is the increased consolidation of soil of the top part of embankment that will allow reducing the design maximum humidity of a roadbed and increase strength characteristics of the soil basis. Statistical dependencies of physicomechanical properties of roadbed soil on its humidity and density in the conditions of the South of Russia are determined. Calculation formulas for structural design of roadbed are recommended.
Calculation of circular plates with assuming shear deformations
Authors: Tyukalov Yu Ya
Published: December 2019

The problem of calculating circular plates by the finite element method taking into account shear deformations is considered. Transverse forces can be approximated by constant or piecewise constant functions. The necessary relations for triangular finite elements are obtained. It is shown that the proposed method can be used in combination with traditional finite elements for thin plates obtained by the finite element method in displacements. A comparison of the solutions obtained by the proposed method with other known solutions for circular plates regarding shear is given. It is shown that displacements from shear deformations are determined independently of displacements associated with bending. The obtained results demonstrate the convergence of the solution to the exact one when grinding the finite element mesh and good accuracy for considering shear deformations.
Possibility of using super-thin liquid thermal insulation for protection of steel beams embedded in brick wall exterior under building reconstruction
Authors: Polyakov V G , Chesnokova O G , Cherednichenko T F
Published: December 2019

The article presents the results of calculations on changing the thermophysical properties of the connectivity node of the outer wall and the balcony plate resting on the cantilever fixed steel beams. A variant of insulation of steel beams with super-thin liquid insulation under the reconstruction of existing brick buildings with single-layer brick walls is proposed. The graphical analysis of the problem was carried out. The results of calculations of temperature with linear thermophysical properties show that the method of steel beams insulation within the conditions of reconstruction of residential buildings makes it possible to increase the building life. When using super-thin thermal insulation coatings, it is possible to reduce the local freezing of the balcony plate.
Low-cycle fatigue of concrete with alternating loads
Authors: Pinus B I , Kustov A S
Published: December 2019

The article deals with issues related to the assessment of fatigue effects during alternating effects of the external environment. The results of an experimental statistical analysis of the strength, deformability and resistance energy of concrete after 100 cycles of variable tension in the differential range are given. Strength and modulus of concrete elasticity is established as an index relatively stable in magnitude and density of distribution. Also, significant changes in the structure, size and distribution of ultimate deformations and their components are found. To the greatest extent, this relates to the potential for plastic deformation, which is confirmed by the drop in the damping capacity and the brittle nature of concrete destruction.
Compressed tube-concrete elements with the high-strength compression core and with fibreglass shell
Authors: Krishan A L , Narkevich M Yu , Sagadatov A I
Published: December 2019

The aim of the work was to assess the strength and deformability of compressed concrete elements with a core of high-strength self-stressing concrete, with strength grade of concrete C80 and fibreglass shell. The concrete core was carried out both with spiral reinforcement of the concrete core and without it. The methodology for testing two series of samples of compressed tube-concrete elements for central compression is described. Comparative data on the breaking load of both series of samples, as well as graphs of relative deformations in the axial and circumferential directions depending on the relative loading levels are presented. It was experimentally established that the presence of spiral reinforcement for 1.8% increased the strength of compressed concrete elements by 9% and increased the effect of the hooping by 11%. The limiting axial deformations increased about 1.5 times. Thus, the device of the spiral reinforcement of the concrete core is one of the rational ways to increase the operation efficiency of compressed concrete elements with fibreglass shell.
Determination of resistance to radon entry of underground walling at stage of construction design
Authors: Bakaeva N V , Kalaydo A V
Published: December 2019

The dose from radon and its progeny is a controlled component of the radiation load on the population, and therefore can be reduced by the use of appropriate construction technologies. The article shows that the convective flow can be reduced to zero by choosing the appropriate floor construction, whereas the diffusion cannot be completely excluded, and the diffusion radon flux can only be reduced to a certain level. An approach to the assessment of the required radon-protective characteristics of the building is proposed under the assumption that there is no convective radon entry. As a radon load on the underground part of the building, the radon potential of the soil, determined by the results of gamma-spectrometric analysis of the soil from the construction site, was used. The procedure for calculating the geometric characteristics of layers with high resistance to radon permeability based on the required radon concentration in the ground floor premises of the building after its construction and the radiation characteristics of the soil on the construction site is shown.
Research of stressed-state stiffened hollow strengthened concrete slabs in cracked condition
Authors: Vasilyev A S
Published: December 2019

In fact, while making engineering calculations, hollow slabs are presented as T-shaped and I-beams. In this case, the web face of a beam decreases according to the dimensions of cavity pockets inside a slab. The conventional theory of calculating building constructions with breaking stress involves the calculation of such hollow slabs focused on the beam theory. In this paper, the authors observe the stress condition of hollow slabs at failure. Numerical studies are carried out for slabs re-enforced in several ways. The authors perform calculations in nonlinear formulation with gradually increasing stress before the samples were distorted. The researchers compare the stress condition in the slabs with normal cross-sections to the stress condition in the similar I-beam slabs. The aim of the study is to outline the way the cross section shape representation influences the results of direct stress in section and the cracking moments from the bending moment in the center of the slab span. The scholars take into account various methods of reinforcing hollow-core slabs. The paper emphasizes that the moment of crack propagation for hollow slabs in a normal shape comes later than for I-beam slabs.
Investigation of glued in bars strength and deformability indexes within framework of research of wood reinforcement with cable reinforcement
Authors: Koscheev A A , Lukin M V , Roshchina S I
Published: December 2019

The increasing demand for the low-height housing construction frame technology keeps current the issue of saving timber in building construction. The method of reinforcing beams with reinforcing steel is a promising direction of research in the field of ensuring the gain in strength and the cost indexes reduction of structures. In 2017 as a graduate student of the Department of building structures of VlSU Koscheev A.A. proposed for the investigation a new type of reinforcing wooden beams by the steel cable reinforcement in solid wood along the original curvilinear trajectory. As of today, a number of numerical investigations in this area was carried out and the process of the full-scale experimental investigations was launched. This research article is devoted to the first cycle of the experimental analysis in this area: investigation of the influence of the steel wire rope strength characteristics on the behaviour of the adhesive interlayer of the epoxy composition when conducting tensile tests – pulling out a straight bar from the solid wood. On the basis of the data obtained, conclusions on the applicability of the rope reinforcement in solid wood constructions were drawn and the main directions for further research were determined.
Calculation for stability of centrally compressed rods of steered stiffness in existence of linearly deformable connections
Authors: Grebeniuk G I , Liuft N A , Nikolskii A V
Published: December 2019

The authors consider one-parameter problems of calculating the stability of centrally compressed rods of step stiffness with linearly elastically compliant support constraints. The problem of calculating the stability is set as bifurcation. Euler’s exact solutions are obtained for different variants of the design scheme of a rod of two-stage rigidity. An iterative algorithm for calculating the stability beyond the limit of proportionality is proposed, based on the concept of the conditional flexibility of rod sections, using the experimentally obtained diagram σ - ε and the table of coefficients ϕ. Numerical examples illustrating the proposed methods and algorithms are considered.
Numerical simulation in diagrams for concrete deformation in computations of strength of reinforced concrete elements in deformation model
Authors: Eryshev V A
Published: December 2019

The paper establishes correlation between the integral parameters of nonlinear diagrams for concrete deformation in the versions of Russian and foreign regulatory documents applied to computation of strength of the reinforced concrete elements in the deformation model. It is recommended to use the fragments of the areas boarded by the branches of diagrams, as well as the coefficient of the diagram completeness as integral parameters of the diagrams for concrete deformations. The diagram area with the predetermined values of the element curvature is equivalent to the value of the ultimate strain in the compressed zone of concrete in the bendable elements under off-center compression, and the geometry of the stress diagram corresponds to this diagram. The study offers analytical expressions establishing the connection of strength and deformation parameters for the classes of concrete, which have standard values of deformation and stress in the reference points of curvilinear diagrams. The article presents the results of the computation and establishes the interconnection between the parameters of diagrams obtained by analytic correlation between stresses and deformations in the considered regulatory documents. There are recommendations for defining standard integral parameters of diagrams in calculating the strength of reinforced concrete elements using the deformation model.
Transformable structures
Authors: Gnedina L Y , Dolgusheva V V , Danko V V
Published: December 2019

This research explores different types and forms transformable structures as an integral part of any building or construction. The structures, which are capable of changing its spatial position or geometric shape, become an individual branch of architecture and design. However, with all diversity of known structural shape-shifts, there is no comparison of its types with existing buildings. Thus a purpose of this research is studying about worldwide experience in development of transformable structures. Another goal is comparison of known classifications with examples of shape – shifts in built projects based on following study. The internet search along with the review of related literature references was done. By the completion of survey the authors matched given examples with the classification of transformable structures by methods of realization and approaches to motion arrangement. The scissor – structures category is derived into separated stratification as well. The study showed that the structures that can rearrange its shape have a great potential as kinematic objects of architecture and engineering.
Time of dynamic impact to elements of RC frame at column buckling
Authors: Fedorova N V , Savin S Yu
Published: December 2019

A method for calculating the time of the dynamic additional impact to the elements of a reinforced concrete framing structural system under special impact caused by a sudden loss of stability of a compressed bearing element is presented. Using the discrete-linear moment-curvature diagram for reinforced concrete compressed-bended element, the analytical relationships for different stages of deformation of a reinforced concrete element before and after cracking are carried out. The obtained relationships for time of the additional dynamic impact to the elements makes it possible to determine the dynamic strength of concrete and reinforcement and the stiffness of the sections of reinforced concrete elements of structural systems under such impacts more accurately and consequently ensure more exact computational analysis to progressive collapse.
Strength and deformation property enhancement of compressed steel tube-concrete elements using super concrete and thin-shell structure
Authors: Narkevich M Yu , Sagadatov A I
Published: December 2019

The article analyzes the changes in the strength and deformation property of compressed steel tube-concrete elements when the quality indicators of the original concrete (strength class for axial compression) and the metal shell are changed. The methodology of testing for central compression of steel tube – concrete columns with a core of ordinary and super concrete with a thin-shell structure is described. Comparative dependences of the relative deformations in the axial and circumferential directions depending on the relative loading levels, destructive load values for samples from ordinary and super concrete are presented. According to the results of the research, it was determined that with an increase in the class of concrete, the efficiency ratio of the concrete is reduced by an average of 12%, however, the increase in bearing capacity remains quite noticeable. In addition, the use of high-strength concrete class C80 increases the deformability by about 10% compared with concrete class C40 steel-concrete columns, with significant savings in metal.
Modelling framework joints in ANSYS software complex
Authors: Buzalo N A , Alexeeva A S , Chernykhovsky B A
Published: December 2019

Modern methods of building design are largely based on the creation and analysis of a 3D model of a structure in a specialized CAE complex using the finite element method. The article describes the problem of designing the junctions of crossbars and columns in the metal frame of high-rise buildings. A computational model of a flange joint is created in the form of a solid three-dimensional model in the ANSYS software package, a visual display of equivalent stress fields was obtained, and the calculation results are analyzed. The method of strength analysis of junction points of frame systems using CAE systems makes it possible to more effectively take into account many options in the design due to the system of parametric values, and also analyze in more detail the stress-strain state of the calculated structure.
Construction of discrete analogs of differential equations for bending of plates and shells with discontinuous parameters based on spline approximation method
Authors: Katerinina S Yu , Voronkova G V , Rekunov S S
Published: December 2019

A new approach to the construction of discrete analogs of the differential equations of bending of plates with discontinuous parameters based on the two-dimensional spline approximation method is proposed. At its core, it is close to the Finite Element Method, since all constructions at the beginning are carried out for a single cell of a finite element, and then applied to the entire area surrounding the base node. The use of such a technique makes it possible to reduce the number of unknowns in each node of the grid area, and the introduction of parameter gaps into the resolving system makes it possible to take into account their effect on the stress-strain state of the structures. This approach to the construction of discrete analogs of partial differential equations allows developing a universal method for constructing discrete analogs of these equations. This technique will significantly reduce the amount of computation in the strength analysis of buildings and structures of various functional purposes using lamellar and shell elements.
Experimental investigations of composite wooden beams with local wood modification
Authors: Gribanov A S , Rimshin V I , Roshchina S I
Published: December 2019

The dynamic development of wooden structures is inherently connected with emergence of the new structural elements having high operating parameters, increased strength and rigidity. Composite wooden structures based on wood and reinforcing material made from glass, aramid or carbon fiber on a polymer matrix fully comply with the requirements. The complex stress-strain state that occurs in the reinforced wooden elements necessitates a plainly required experimental confirmation of the assumptions and suppositions taken as theoretical. Comparative analysis of the theoretical and experimental investigation of wooden beams reinforced with carbon fiber polymer composite and modification of the wood compressed zone has been performed as a part of the research. Test installation for testing beam structures is presented, “load-strain relation” and relative deformation diagrams in the cross section of wood-composite beams are constructed. The stress-strain state of the structures at various stages of loading is analyzed. Sufficient convergence of the results of the experimental and theoretical investigations is established. The discrepancy in the first group of limit states does not exceed 3.5%, in the second group does not exceed - 9%.
Stability of compressed sheathings of wood composite plate-ribbed structures
Authors: Labudin B V , Popov E V , Sopilov V V
Published: December 2019

Wood composite plate-ribbed structures working under the conditions of lateral bending in coverings and floors in buildings of various purposes are considered. The results of studies of the influence of various parameters on the stability of the upper compressed sheathing of wood composite panels with bonded joints of sheathings and ribs (type of connections, coefficient of stiffness of the bonded joints, span size, width of panels and material of anisotropic sheathing) are presented. To implement the task, the Lekhnitsky theory of calculating the stability of anisotropic plates is used, in particular, the energy method for determining the critical force for a flat anisotropic plate loaded along the edges by tangential efforts. For describing the distribution function of tangential efforts on the edges of the sheathings, the Rzhanitsyn theory of calculating composite rods is applied. As a result of numerical studies, the coefficients of longitudinal bending, which can be used in the engineering calculation of wood composite panels with mechanical and glued joints are obtained.
Determination of stresses in truss rods: numerical and physical experiment
Authors: Kiychenko T S , Tabanyukhova M V , Kharinova N V
Published: December 2019

The paper presents the results of an experimental numerical study of the stress state of the rods of a flat truss. The values of internal forces and stresses in the truss model were obtained using the SCAD software package, as well as experimentally using the polarization-optical method. The finite element method (FEM) is used to calculate two plane truss models. In the first case, the truss was modeled by rod elements, in the second – by plates. The fields of normal, tangential and principal stresses are obtained. Based on them the longitudinal internal forces in the rods of the farm are determined. The captins of interference bands in the model of a flat truss are obtained by the method of photoelasticity. Stresses are calculated with their help. The quantitative and qualitative analysis of the stress state, described in the numerical and physical experiment, is carried out.
Use of monitoring system in Ekaterinburg
Authors: Avdonina L , Alekhin V , Shipulin E
Published: December 2019

The monitoring of buildings and structures condition, as well as the timely implementation of corrective actions aimed at the elimination of adverse factors, are the most important aspects that shall be addressed at the construction stage. The usage of monitoring systems makes it possible to monitor the building condition and above that to implement more efficient design solutions in the prospective projects using the results of the analysis of the acquired and design data. In this work the review of a monitoring system installed in a high-rise building located in Ekaterinburg is given. The paper describes the analysis of the natural oscillation frequency and the logarithmic decrement of fundamental tone acquired with the help of accelerometers, and compares the values with the acceptance limits. The process of converting data acquired by strain gauges for the determination of the stress-strain condition of the bearing structures is analysed. The process of comparison of data obtained by the monitoring system of a high-rise building is described. The necessity of the application of the monitoring system is analysed.
Phase composition of cement brick after different time of low temperature curing
Authors: Gnyrya A I , Abzaev Yu A , Korobkov S V
Published: December 2019

The paper presents a study of the quantitative phase composition of cement brick using the Rietveld method, after the different time of its isothermal hardening at 40 °C. With a high degree of reliability, it is established that Ca6H2O13Si3 and Ca3HO9Si3 are major phases of cement brick. The presence of hydrogen atoms is taken into account in the specified lattices. X-ray diffraction measurements and the mass fraction of these phases provide the theoretical calculations of their contribution to the integrated intensity. It is shown that the lattices of the studied phases are in a highly stable state, and their binding energy tends to increase with the increasing time of curing. One can observe spatial redistribution within the lattice stability and variation in the number of atoms in the unit cells. The lattice stability interval allows a certain spatial redistribution of Ca, H, O and Si atoms inside the lattices.
Designing of organizational and technological solutions for construction in constrained urban environments
Authors: Chebanova S A , Polyakov V G , Azarov A V
Published: December 2019

The article substantiates the need to improve the quality of design work on the construction site in the context of the existing urban development taking into account specific criteria and gradations. The features and problems of the main periods of construction are investigated. To improve the quality of the design documentation, in particular, of the construction work program in constrained urban conditions, the authors conducted the research of the influence of a complex of constraint factors affecting construction preparation activities. Recommendations of construction site organization in the current conditions are given. The results are presented and further research stages of technological processes in constrained urban conditions are outlined. We show the expediency of a systematic approach to improving the quality of construction’s process. We are taking into account the assessment of environment state and the need to reduce the negative impact of construction and assembly works on nearby already built-up areas. The need to take into account the above factors for developing a project of works execution is justified.
Innovative assembly line for building and major repair of main pipeline
Authors: Akhmedov A M
Published: December 2019

The article proposes an innovative assembly line for pipe sections under field conditions excluding pipe layers. With the suggested assembly line the alignment of pipe sections can be done for welding works. Apart from this, the proposed line can help in insulation works, support of pipeline section, and laying of the finished pipe section onto a special supports along the trench. can be performed. The assembly line is equipped with hoists enabling to lift pipe sections and finished strings without lifting facilities used in conventional technique which will considerably improve environmental situation and cut financial expenditures. The offered assembly line will considerably improve the equipment of the repair and construction site as well as improve the working conditions of the personnel. The assembly line is fully electrically powered which makes it ecologically friendly. An innovative assembly line is treated in the article that is adapted to operate on the construction site. The line was developed as multi-functional one. With the help of this proposed line, there is the opportunity to fully automatize erecting and sheathing and laying works. The application of special anchor-type supports will make it possible to provide a spatial stability while performing the jobs.
Features of estimation of intangible resources of investment and construction activity in cyclic dynamic
Authors: Peshkov A V
Published: December 2019

The current level of development of the economy of the Russian Federation and in particular the construction industry requires the development of a system of management of material and intangible resources. The article reveals the nature of intangible resources in the investment and construction sphere. It is proved that a large reserve for the growth of economic efficiency of investment and construction activities is the use of intangible resources. As a result of the analysis of the value and characteristics of intangible resources of investment and construction activity, the target orientation of their reproduction in the process of construction projects implementation is determined. A new trend in the development of investment and construction activities, which is to accelerate the rate of expanded reproduction of intangible resources of the activity. In the analysed construction industry the development of a system of management of material and intangible resources plays an important role in ensuring the effective development of the enterprise. The author substantiates the need for the use of intangible resources depending on the types and phase of the investment and construction process. Each type of intangible resources has a set of specific features characteristic of each phase of economic turnover. In the future, this study will be relevant for the development of proposals for the expanded reproduction of intangible resources.
Development of new tool joint for modular systems made of cellular polycarbonate
Authors: Abramyan S G , Polyakov V G , Grunin A V
Published: December 2019

The paper discusses the use of solid and structural polycarbonate modular systems in energy efficient facades and roofs of unique modern buildings. Inferior to nearly all translucent materials by light transmission, cellular polycarbonate sheets offer a combination of important consumer properties, such as impact resistance, light weight, flexibility and chemical stability. At the current stage of construction development featuring cellular polycarbonate modules, the assembly (installation) fails to meet the constructability and work safety requirements. To address these drawbacks of cellular polycarbonate structural modules, a new butt joint is suggested consisting of two separate C and T shaped profiles, where one joint profile is placed inside the other one’s cavity after their fastening to a cellular polycarbonate sheet. To build a variety of most complex curved enclosures, the coupling parts can be rounded similar to existing ready-to-use cellular polycarbonate sheets with U-joints. The paper outlines the installation of cellular polycarbonate modules with the new joint profiles. To improve the constructability of vertical translucent enclosures, modular systems can be enlarged on special benches and installed using vacuum lifting beams. The reliability and safety of the new structures is ensured by extensive profile resting upon metal or other load bearing supports.
Emergency ventilation industrial premises of chemical industry enterprises
Authors: Zherlykina M N , Kononova M S , Vorob’eva Y A
Published: December 2019

The results of the study concentration field of chemical harmful substances in the entire volume of the room during the operation of emergency ventilation with a given air exchange are proposed. Explosion safety of production rooms is provided on condition of 10 % of the lower limit of flame spread on gas-air mixes and observance of equality of concentrations of harmful substance in the working zone and in the leaving air. Emergency ventilation is proposed, which provides uniform removal of air from the entire volume of the room to exclude the formation of stagnant zones and ensure explosion safety in chemical emissions. Emergency ventilation with a natural flow of air through the holes with variable aerodynamic characteristics with a volume-oriented arrangement of supply and exhaust holes to ensure uniformity of the flow and removal of air from the entire volume of the production room.
To assessment of heat saving in automation of buildings heating systems
Authors: Panferov V.I. , Panferov S.V.
Published: December 2019

The paper considers the problem of estimating the magnitude of heat savings in the automation of building heating systems. Its authors propose a fairly simple method for determining the relative efficiency of the heat losses of a building in various temperature regimes. The plausibility of the savings data available in the literature is analyzed. The research provides approximate estimates of the savings for real situations. The practical value of combined heating systems using, in particular, renewable and non-traditional energy sources is estimated. It is indicated that the cost of heat to maintain a given temperature mode is determined by the physics of the heat exchange process of the building, so they are the same with any heating system. As a result, the combined system has no advantages over other types of heating systems in terms of heat consumption.
Selection of well screen parameters as aspect of water well design
Authors: Akulshin A A , Shcherbakov V I , Uchaev A S
Published: December 2019

This paper addresses an essential problem within the scope of the issues of optimum design, construction and operation of water supply systems and their elements. The water well is the core element of the groundwater intake structure. The quality of water well design and construction workmanship are pivotal for successful operation of the intake structure in general. Poor well design and errors in well construction result in malfunctioning of the whole water supply system. Selecting an appropriate water well screen to conform to specific geological conditions and to ensure the longevity of the well structure itself is a complicated engineering problem. The estimation of well screen parameters covers such dimensions as length, diameter, open area ratio and aperture (slot) size. Those characteristics must be determined taking into account that the entrance velocities must not exceed the entrance velocity limit for a particular screen, i.e. V
ent ≤ V
lim.
Comparing pipelines made of different materials for replacement of old on-site pipelines of Kinel pumping-filtration plant
Authors: Gorshkalev P A , Chernosvitov M D , Nikitina D S
Published: December 2019

The article focuses on the pumping-filtering plan (PFP) in the town of Kinel and describes the pipes of various diameters made of modern materials. The authors compare characteristics of pipelines produced by four different manufacturers to choose pipeline materials which are most suitable for this particular pumping-filtering plan. The comparative analysis of the pipeline materials makes it also possible to decide on several options for use in reconstruction. The authors further consider characteristics of materials from which pipelines for water supply and heating systems are made. They describe metallic materials (steel, copper, zinc, stainless steel) and polymers (polyethylene, polyvinyl chloride, polypropylene and fiberglass). In the end the researchers share their experience and explain how water supply pipelines made of different materials operate in normal working conditions.
Study of mutual work of Coanda channels in local ventilation systems
Authors: Kireev V M , Goltsov A B , Alifanova A I
Published: December 2019

Today, the Coanda effect is widely used in many technical areas, in particular, ventilation systems. However, this effect occurs only when a certain combination of many factors affecting the moving stream. The occurrence of the Coanda effect is unstable and is easily disturbed when interacting with another air flow of a non-coincident trajectory. The article describes the method of air supply, which consists in the use of two channels arranged in series in which a stable Coanda effect occurs. The arising effect is explained by the interpretation of the fundamental laws of hydrodynamics. The article presents the results of an experiment on the use of the proposed solution in the recirculation system of aspiration, with the use of which there was an increase in the efficiency of work by 51%
Modelling and optimizing engineering network systems
Authors: Lvovich I Ya , Preobrazhenskiy A P , Choporov O N
Published: December 2019

This paper is connected with the necessity of problem orientation of invariant methods of mathematical modelling and numerical optimization on formation of effective engineering network systems with cluster structure both at the stage of their functioning and development. In this regard, several problems are considered. Optimization modelling of engineering network system efficiency with cluster structure is carried out. Numerical optimization of engineering network system resource efficiency is demonstrated. Numerical optimization of structural and resource (combined) efficiency of the engineering network system is carried out. The results of the paper can be useful in choosing an effective implementation of the complex components of engineering networks on the basis of a computational experiment, to carry out a cluster structuring of the engineering network system of the network system by private indicators and integrated assessments of the efficiency of the functioning of its constituent objects.
Use of compressed gas heat utilizers in gas-compressor units
Authors: Medvedeva O N , Astashev S I
Published: December 2019

The study considers the possibility of using the Ranque-Hilsch vortex tube in the construction of a heat exchanger for heating fuel gas to ensure normal operation of the gas-pumping units used to pump gas into the underground gas storages. According to the results of the gas-hydrodynamic and thermal methods for calculating structural elements, a final equation was obtained describing combined operation of the vortex tube and heat exchanger. The calculation method allows taking into account the impact of the main temperature and design parameters. The results of technical and economic calculations and thermal modeling based on the SOLIDWORKS program make it possible to judge the effectiveness of the proposed design.
Study of factors affecting reliability and efficiency of heat supply system
Authors: Biryuzova E A
Published: December 2019

Reliable and uninterrupted supply of heat to consumers is the most important task of the heating system. Due to the connection to the heat network of a large number of dissimilar consumers, the heat supply system operates year-round. Damage to heat networks can lead to disconnection of consumers, disruption of internal engineering systems, and reduction of their operation parameters, which can be dangerous, especially during the heating period at low outdoor temperatures. To ensure the reliability and efficiency of the heat supply system, it is necessary to fulfill all the requirements of the technical operation rules, conduct timely rounds and inspections and identify damage to the heating network at an early stage. It is also necessary to identify factors affecting the reliability and, consequently, the efficiency of the heating system, identifying “risk zones” by the magnitude of damage, based on the results of the calculation. As well as the development of measures to identify and prevent failures in the heating system.