bluuebunny/crossref_metadata_2025 huggingface dataset:
Optimal Planning and Efficient Adjustments of the Terms of Constructions
Authors: Tsapko K , Melnikov L
Published: March 2020

Effective planning and implementation of large capital investments, hundreds of millions of dollars can be saved. After completion of the project, it is extremely difficult to make adjustments: even the most talented plant Director, increasing labor productivity, will not be able to compensate for the costs and losses caused by the unsuccessful arrangement of equipment and irrational design of the areas. Companies often trust the choice of optimal technology and configuration to construction organizations. The article deals with the issues of effective optimization of construction scheduling. The specific methods of it mechanisms of reduction of construction time, prevention of overspending of resources, increase of economic efficiency of construction in general are offered.
The Algorithm for Solution of the Inverse Task of the Inclinometric Control during Geotechnical Monitoring of the Foundation of Building
Authors: Grecheneva A V , Kuzichkin O R , Kovalenko A O , Kurilov I A
Published: March 2020

The article discusses the algorithm of the solving of the inverse problem of the determining of the load parameters of foundation during geotechnical monitoring using inclinometric control. The method of the inclinometric control of the foundation is based on the data of accelerometric sensors with using the phase-measuring principle of the control and the regression analysis to determine the load parameters of the foundation. The developed algorithm allows you to localize the foundation section with the violation of the balance of the forces in the “structure-foundation-soil” system, which leads to foundation deformations. The columnar type foundation is considered as an example.
Some Trends in the Formation of Recreational Spaces in Urban Development
Authors: Dorozhkina E A
Published: March 2020

The article deals with the experience of building modern areas. This is due to the fact that they have the characteristic features of an urban environment. Often it is in them against the background of increasing density of buildings and simultaneous remoteness from the center there is a lack of quality recreational areas. In this case, it is about improving the quality of the environment, not meeting the minimum allowable requirements for the environment. The necessity of forming a green component in recreational spaces is indicated. The classification of green areas in the structure of building is considered. The purpose of recreational spaces is defined. The principles of recreational spaces in the modern urban environment and features of their formation are considered.
Analysis of the Flexibility of a Soft Hinge with a Floating Power Connection
Authors: Bykova E O , Kamaletdinova G R , Sorokin A E
Published: March 2020

Providing high safety standard for aerospace field is one of the most important issues that designers and engineers must face [1, 2]. It is especially important for life support systems, which consist of a set of tools used to ensure human safety while maintaining high performance. However, human needs to have a stable and comfortable environment inside the suit, as well as an appropriate suitable and high-tech equipment. One of the most important problems in the development of perspective spacesuits (extravehicular and rescue) is the flexibility of the legs and especially the arms of the spacesuit. Ideally, the level of flexibility of the spacesuit should correspond to the level of flexibility of a person in ordinary clothes.

This paper presents an analysis of the flexibility of a soft hinge with a floating force connection, guaranteeing the mechanical flexibility of the soft hinge elements. The advantages and disadvantages of corrugated joints are discussed. Conclusions have been drawn on the relevance of using soft joints with a floating force connection in space suits, especially in gloves. This paper discusses requirement analysis on the materials used for gloves manufacturing as well as test procedures used to the requirements control.
Taking into Consideration the Work of Monolithic Reinforced Concrete Floor with Shaped Steel Profiles in Two Directions
Authors: Roshchina S I , Gonshakov A G , Gonshakov N G
Published: March 2020

The publication is devoted to the study of the work of monolithic reinforced concrete floor with shaped steel profiles in two directions. Theoretical and experimental studies on models of the plate were made. To evaluate the stress-strain state of the slab reinforced with profiled flooring during operation, under the action of a uniformly distributed load, the theory of structurally orthotropic slabs supported along the contour was used. A technique has been developed for determining the bearing capacity of a slab based on the method of limiting equilibrium. The field of application of the developed methodology for calculating square and quasiquadratic monolithic plates with steel profiled flooring is substantiated. Putting into practice the construction of these floors, designed taking into account their work in two directions, can reduce the consumption of steel (steel beams) up to 50%, concrete up to 8% and labor at the construction site up to 22% per 100 m2 of the covered area compared to the calculation of the proposed structures according to the beam scheme. These structures are recommended for use in coatings and ceilings during the reconstruction of buildings, as well as in new construction.
Protection of Tent Materials on the Basis of Capron Using Polymers
Authors: Strigin B S , Stepina I V
Published: March 2020

The object of the paper – is to improve abrasion resistance of capron-based awning material. The objectives of the present research are the following: to investigate the impact of polymer compounds, on the base of urethane thermoplastic material UK-1 structured by A-grade polyisocyanate, on the base of Z-grade chlorosulfonated polyethylene containing vulcanizing agents, stabilizers and pigment groups, on abrasion resistance of awning material with the pressure base of capron fabric. Research methods: test samples have undergone the complex of laboratory experiments for alteration of parameters of physical and mechanical properties before and after accelerated heat-and-light ageing in the STS apparatus. Abrasion tests have been carried out on the PIT-2 apparatus. Instrument measurements of physical and mechanical properties as well as visual evaluation of protective polymer coatings’ state have been taken as control parameters of abrasion resistance. Results obtained: the investigation has shown that abrasion resistance of soft barriers of awning structures and, correspondingly, their service life could be increased essentially by means of applying an additional layer of protective screen coating and its intermittent resurfacing adjusted for wear while in service. Re-surfacing intermittence should be done every 2 years provided the coating thickness of 100 micrometers.
Application of Textile Reinforced Concrete in Precast Concrete Industry
Authors: Holschemacher K
Published: March 2020

The sales of Germany’s precast concrete industry have been almost 6 billion Euros in 2017. This is only a small part of total construction investments but precast concrete industry traditionally is open-minded for implementation of innovations. Consequently, many new trends in civil engineering have been started in precast concrete industry. Recently, Textile Reinforced Concrete (TCR) has got more and more attention for application in precast members.

Basic idea for the development of TRC was the intention to replace the traditional steel bar or steel mesh reinforcement by textile meshes on the basis of alkali-resistant glass fibres, carbon fibres or basaltic fibres. By this method it is possible to avoid the corrosion problem of the steel-based reinforcement and to improve the durability of precast concrete members. However, there was not a real break-through of TRC in construction practice until 2010. Main reason was the preferred usage of glass fibre meshes as textile reinforcement and the limited load-bearing capacity.

The last step in the development of TRC is the application of carbon fibres for the production of mesh and bar reinforcement. Carbon meshes and carbon bars may be used combined or separately as reinforcement resulting in a new construction material called Carbon Concrete Composite. Based on the outstanding properties of carbon fibres it is possible to enhance essentially the application possibilities of TRC. The paper describes the basics of the production and approaches for the design of Carbon Concrete Composite members and reports first applications in construction practice.
The Research of the Stress-Strain State of the Pipeline System, Taking into Account the Change in Spatial Location
Authors: Kulakov P A , Afanasenko V G , Bayazitov M I
Published: March 2020

In the work, the influence of changes in the geometry of the technological pipeline on the stress-strain state is studied, taking into account the complexity of the strapping of technological equipment and the parameters affecting the deformation. The authors analysed the stress-strain state of technological pipeline systems with a change in their spatial location, simulated 3 options for the spatial location of the pipeline system. The best option was selected to ensure its reliable operation, depending on the design parameters. In conclusion, the effect of hydraulic load on the VAT of the pipeline was investigated. The calculations were carried out according to the standard method in the PC program “Start” and using the finite element method in the PC SolidWorks. It is established that a change in the geometry of the pipeline system significantly affects its stress-strain state. On the example of changing the geometric arrangement of equipment piping shown the possibility of reducing VAT in the pipe bends by 19%. It is shown that when assessing the strength of technological pipelines with complex geometry and a significant number of elements, it is necessary to take into account hydraulic loads, which can increase the VAT in pipeline elements up to 21.7%.
An Assessment Tool for Impacts of Construction Performance Indicators on the Targeted Sustainability of a Company
Authors: Lapidus A , Abramov I
Published: March 2020

A construction company is a dynamic system capable of transforming and passing from one quality state to another while retaining its system quality due to its properties including:

- Effectiveness – ability to produce a result and to create products required by consumers;

- Flexibility – ability of the production system to adapt to ever-changing external environment;

- Durability – ability of the production system to produce results over a long period;

- Manageability – acceptability of temporary changes in functional processes in the desired direction influenced by control action;

- Reliability manifested in sustainable functioning that is ensured by the management system, cooperation with other production systems, and internal reserves.

In this connection, the authors of this article have set an objective of selecting a descriptive and effective instrument of estimating losses of statistical control and, accordingly, the targeted sustainability of a construction company at the current stage of economic development in this country. They also expand on the notion of functional sustainability of construction companies as a dynamic production system.

This article is focused on development of recommendations with a view of achieving the targeted functional sustainability level of construction companies in present-day conditions and disturbances.

Therefore, sustainability is examined in this article as a multidimensional emergent property of a construction company viewed as a dynamic cybernetic system designed to manufacture construction products and to maintain its systemic quality in interaction with production processes.
The Stabilizing Additive from Natural Zeolite for Stone Mastic Asphalt
Authors: Kopylov V E , Burenina O N
Published: March 2020

The article describes the possibility to use natural zeolites as a stabilizing additive for Stone mastic asphalt. Stone mastic asphalt is highly resistant to damage caused by traffic and natural climatic conditions. It is possible to use natural zeolites economically exploited in the Republic of Sakha (Yakutia) as a stabilizing additive, a characteristic feature of which is the presence of voids and channels threading through the entire frame in a dense lattice. In this study, comparative tests of crushed stone-mastic asphalt with various stabilizing additives. As a control group of samples, the stabilizing additive “Stilobit” was used. As a result, data were obtained that natural zeolites are suitable for use as stabilizing additives in the composition of crushed stone-mastic asphalt concrete. In this study, according to the test results, it can be concluded that the natural zeolites are suitable for the use as a stabilizing additive in the composition of stone mastic asphalt. Preliminary mechanical activation of zeolites allows improving the “stone material - binder” interaction at the phase boundary, which is confirmed by improved water resistance parameters of SMA.
Risk of Anthropogenic Cryopeg Formation in Urban Areas in Central Yakutia
Authors: Pavlova N A , Danzanova M V
Published: March 2020

Yakutsk, the largest city in the continuous permafrost zone, is used as a case study for examining natural and modified environmental conditions that control the character and intensity of water-logging in the active layer in relation to topography and drainage. Interpretation of aerial photography and satellite imagery was carried out, along with analysis of drilling and long-term hydrogeochemical monitoring data, in order to determine the response of natural landscapes to human impacts and to assess the probability of suprapermafrost cryopeg development with city expansion. The role of vegetation cover in controlling the temperature and moisture regime of the active layer was examined. Results suggest that the neighborhoods with chaotic development patterns and impeded drainage have high risk of cryopeg formation. Puddle water in these areas is characterized by high dissolved-solids levels (2-4 g/dm3). As puddles evaporate, salts settle on the underlying soil surface and then migrate into the active layer, increasing its salinity (up to 1.3%). Suprapermafrost water that forms in these soils has dissolved-solids concentrations as high as 8–10 g/dm3. Continuous supply of dissolved solids and their cryogenic concentration promote the formation of hydrochemical taliks and cryopegs. Remote sensing and mathematical modeling demonstrate that changes to the soil moisture and hydrogeochemical regimes cause forest degradation, which, in turn, promotes deeper seasonal thaw. This provides favorable conditions for the formation of subaerial water-bearing taliks and later anthropogenic cryopegs
Heat and Mass Transfer of a Coolant in Horizontal Seasonal Cooling Devices
Authors: Baisheva L M , Permyakov P P , Bolshakov A M
Published: March 2020

The heat-mass transfer in the seasonal cooling device with air coolant is considered in this article. This device works during the cold period of year at the expense of the difference between temperatures of soil and air. Their thermal calculation which comes down to drawing up thermal balance for determination of temperature of coolant, being its main characteristic is considered. The engineering method of calculation of heat fluxes of the soil and the pipeline laid in the thickness is developed. Also, there were made a natural measurements of the cooling system. Experimental research was made for the purpose of establishment of qualitative and quantitative regularities of communication of the key parameters characterizing operation of the seasonal cooling devices: air temperatures and speeds of its circulation with the defining factors – the air temperature, wind speed, temperature of soil and its heat-physical properties. Results of researches were used also as the actual material during the checking and justification of theoretically determined formulas.
Seasonal Variations of the Amplitude of the VLF Radio Signals and the Intensity of the Atmospheric Electric Field in Cryolithozone Conditions
Authors: Korsakov A A , Kozlov V I , Toropov A A
Published: March 2020

It is performed an analysis of seasonal variations of the parameters of the underlying surface under cryolithozone conditions far from industrial interference at the SHICRA SB RAS radiophisical polygon near Yakutsk. Seasonal variations of the parameters of atmospheric electricity and the very low frequency (VLF) radio waves propagation from 2009 to 2018 are presented. It is obtained that for summer season the atmospheric electric field near the earth’s surface has a recession due to summer defrosting of the upper layer of permafrost and underlying surface conductivity changes and an increasing of radon output permeability. There is a slight decreasing of amplitude of VLF radio navigation signals received in Yakutsk in summer period. There is an asymmetry in seasonal daytime variations of the VLF signal amplitude. The VLF amplitude during autumn equinox more closely to summer solstice. The asymmetry determined by the season electron density profiles of the ionospheric D region.
Experience of Application of High Durability Concrete for Transportation Structures in Severe Conditions of the Far North
Authors: Matveeva O I , Fedorova G D
Published: March 2020

The article presents the experience of using concrete of increased durability for transport structures in the harsh conditions of the North. The main factors determining the durability of concrete are considered, first of all, the quality of local materials for concrete preparation and methods for producing concrete on its basis for arranging road and airfield pavements both from monolithic and prefabricated reinforced concrete slabs of PDN and PAG grades. The results of laboratory studies of PFM-NLK effect complex modifier, specially designed for use in the Far North on the properties of concrete mixture and concrete, which determine its durability are analyzed. The results of testing preparation of concrete at various industrial enterprises, with introduction of products production and production of monolithic coatings at various objects of transport construction are presented. The possibility of developed technologies spreading for production of increased durability concretes in the Far North regions, including during development of the Arctic regions of Russia and the Republic (Sakha), due to the difficult conditions of the region’s harsh climatic and freezing and soil conditions, and economic and environmental conditions is shown
Restituting the Initial Function to the Historical Rental Houses
Authors: Aksenova I V
Published: March 2020

The subject being addressed in this article is timely because it suggests not only the search of resolutions for the dwelling problems, but also the preservation of historical and cultural environment in Russian cities and towns by returning the initial functions to rental houses. References are made to the RF approved government programs providing restoration of the rental houses institute as the only civilized mode for existence of the rented-dwelling market. Based on the analysis of the rental house construction history in pre-revolution Russia, the article presents the evolution underwent by the structure of multi-apartment dwelling houses. The author has addressed the perimeter-type construction of houses with well-like yards, housing & social complexes for proletariat (the so-called “people’s complexes), rental houses for wealthy citizens, multifunctional complexes of rental houses, as well the condition thereof in the Soviet period. Restitution of initial functions to historical rental houses will help to resolve partially the housing shortage problem and to preserve the historical environment that would comply with the major principle of the sustainable architecture.
The Use of Water Treatment Sludge Containing Clay with Adsorbed Copper and Nickel Ions in the Production of Ceramic Bricks
Authors: Sverguzova S V , Sapronova Zh A , Fomina E V
Published: March 2020

The paper presents the results of research on the use of water treatment sludge, which is formed during the processing of model copper and nickel containing water by activated clays as an additive in the manufacture of ceramic products. It was found that with the addition of sludge, the compressive strength of experimental samples increases from 1.8 to 2.5 MPa. The results of bio testing usingDaphnia magna Strauscrustaceans showed that the aqueous extract does not have an acute toxic effect on the test objects.
Prospects for the Use of Spore-forming Bacteria to Combat the Destruction of Polymeric Composite Materials
Authors: Erofeevskaya L A , Aleksandrov A R , Kychkin A K
Published: March 2020

In order to develop an environmentally and economically sound method of dealing with biological damage of polymer composite materials (PCM), studies of environmental objects (EO) and finished products placed at the site of climatic tests in the city of Yakutsk were carried out. A strain of aerobic spore-forming psychrotolerant bacteria of the genus Bacillus was isolated from a fragment of basalt plastic reinforcement. Its biochemical properties and morphological characteristics were studied. It was found that the resulting strain has the ability to destroy fungi. This property of the Bacillus can be used to combat the bio-contamination of PCM. Biogenic factors of contamination of finished products with pathogenic fungi have been studied. It is established that the soil cover and atmospheric air in the area of the climatic test site contain similar types of microscopic fungi that were isolated from the surfaces of the prototypes. The results of studies on the microbiological characteristics of OOS it is possible to predict bizarrerie and, as a consequence, the biodegradation of PKM, as in the finished product, in contact with the aerial environment and soil cover of the landfill environmental tests found the same species (A. niger and A. fumigatus) with similar biochemical properties, which requires additional research
Production Technology of Heat-Insulating Material on the Basis of Woodworking Waste
Authors: Rudskikh V , Pukhova V , Bobrik A
Published: March 2020

The creation of new thermal insulation materials in the conditions of critical rise in the cost of energy resources is due to the energy saving policy. The most important characteristics of such materials are energy efficiency and effectiveness and environmental friendliness. Scientists of the Siberian Federal University developed a thermal insulation material based on waste wood processing industry. A distinctive feature of the proposed material is cavitation processing of raw materials. The production technology is the following: wood waste as part of the aqueous suspension go through cavitation treatment with the help of a high-speed mixing plant, then the suspension is kept in room conditions for a day, after that the raw material is subjected to hot pressing. As a result of such sequence of technological actions we get the competitive heat-insulating material on heat engineering qualities close to analogues, but with much lower prime cost of its production. Another important feature of this material is the ability to control its final qualities, depending on the mode and duration of cavitation processing.
Theoretical Basis for Designing Seepage-Control Walls in Dam Foundations
Authors: Sainov M P
Published: March 2020

The structures arranged using the method of «slurry trench cutoff wall» or using secant piles are frequently used as seepage-control elements in dam foundations. However, they are designed based on empirical approaches without theoretical validation. With the aid of theoretical modeling the author revealed main specific features of seepage-control walls stress-strain state. They work not only for cross bending but also are subject to bending in their own plane, as well as they perceive considerable vertical forces. These forces appear due to friction between the wall and soil. The author obtained empirical formulae which at preliminary design stages permit predicting maximum values of compressive stresses in the wall at the moment when vertical forces have maximum values. The study made it possible to verify the recommendations for selection of material for arrangement of seepage-control walls. As a rule, deformation modulus of the wall material should not exceed the deformation modulus of the weakest soil by more than two times. Clay-cement concrete or plastic concrete is recommended to be used for the wall material. Its compressive strength is provided due to lateral compression of the wall by lateral compression of soil and groundwater pressure. For not deep «hanging» walls it is possible to use concrete. The assessment was given of foundation deformation impact on the stress-strain state of seepage-control walls. Occurrence of weak interlayers in the foundation causes in the wall appearance of zones concentrating compressive stresses and additional bending deformations. In high dam foundations there is a danger of sharp decrease of the wall compression pressure due to deformations of the foundation lateral expansion. It is not recommended to use the cantilever pattern of the wall conjugation with the dam body, but arrange a concrete gallery above the wall head. Conjugation by a cantilever is possible only for the walls arranged at the edge of the dam profile.
Method of Calculating the Limiting Depth of Ruts on the Pavement of Automobile Roads
Authors: Aleksandrov A S , Dolgih G V , Kuzin N V
Published: March 2020

Proposed the criterion for design pavement, limiting the rut depth RD by limiting value RD
lim
, which depends on the required values of transport and exploitation characteristics. The solution to the problem is based on the classical dependence of the dynamic coefficient on speed at the point of impact of bodies. In this fundamental dependence, the collision speed of the tire with coated is determined by the speed of the wheel and the depth of the irregularities. From this fundamental formula, the functional dependence of the irregularities depth on the speed of movement, the deformation characteristics of the pavement, the power parameters of the moving load (dynamic coefficient), the distance of entry and exit of the wheel from the rut when overtaking another car is obtained. The analysis of the work of specialists of the road industry, which allowed to establish the limit values of all the factors under consideration for coatings, the state of which is characterized by different assessments (excellent, good and satisfactory). For different conditions of coverage, the limiting values of the rut depth RD
lim
are given.
Methods of Reconstruction of Park Territories on Condition of Ecosystem Conservation
Authors: Artemyeva T G , Balzannikova E M , Balzannikov M I
Published: March 2020

The article discusses the process of the urban framework transformation that occurs as a result of the development of urban tissue. The authors analyzed the most common changes in the state of urban park territories, as well as approaches for their further use. The need for structuring the functional areas of park territories taking into account the existing environmental situation is singled out. Two main city park subsystems are identified: ecosystem and recreational environment. The principles of their interaction are revealed. The forms of degradation and destruction of the ecosystem of park territories depending on the factors of aggressive influence are indicated. The authors analyzed the typical functional composition of the park recreational environment. The main characteristics and anthological problems of urban park areas are identified on the example of the author’s concept for reconstruction of the Gorky Park located in Samara city. The universal method of preserving the ecosystem in an urban park environment is proposed, which is based on the principle of segregation of zones and concentration of functional consumer facilities.
To the Shear Strength of Concrete
Authors: Dovzhenko O O , Pohribnyi V V , Zyma O E
Published: March 2020

Interpretations of the “pure shear” phenomenon were presented. The incompatibility of “pure shear” for concrete as a special case of stress state and destruction form was indicated. Due to the variety of cases of concrete and reinforced concrete elements destruction by shearing, it is impossible to establish a concrete shear strength single characteristic, and all its empirical values are particular for individual cases. As an alternative to calculating shear strength, a sufficiently strength calculating general theory of concrete and reinforced concrete elements under complex inhomogeneous stress-strain states, developed on the basis of the ideal concrete plasticity premise on the destruction surface and variational method, was proposed. The developed methodology has been comprehensively tested. An example of using the theoretical results of concrete elements strength solving the problem of the with a two-way strip load application by the variational method in the plasticity theory to determine the concrete strength characteristics was given.
The Regularities of Structure Formation during Friction Stir Processing of Bimetallic Materials Based on Copper and Aluminum Alloys
Authors: Chumaevskii A V , Kalashnikov K N , Gusarova A V
Published: March 2020

The structure of polymetallic materials samples obtained by friction stir processing of a sheet package made from AMg5 aluminum alloy and L63 copper alloy is studied. The regularities of structure formation at the deformation-initiated stirring of system components in comparison with the similar process at sample production from homogeneous materials are determined. The localization of the main defective zones in the samples during coatings formation is studied. Intensive diffusion and mechanical mixing of system components, leading to the formation of a large number of different phases in the “coating-substrate” system, has been revealed.
An Approximate Analytical Solution to the Problem of Heat Exchange in Porous Material
Authors: Kravchuk V Yu
Published: March 2020

The article consists some researches of heat exchange in porous medium. The general formulations of the heat exchange task are presented. The physical meaning and its mathematical interpretation of the task are described. The analytical solution of differential system equation for simply boundary conditions are found. The field of simple mathematical formulation application is detected.
The Importance of Mathematics for Future Architects and Civil Engineers
Authors: Sergeeva E V
Published: March 2020

Since ancient times, the main methods of design belonged to mathematics. Mathematics in Ancient Greece was one of the sections of architecture and was based on the classical geometry of Euclid. And now professional competence of graduates of construction specialties of the University is impossible without the developed mathematical competence. Developing mathematical competence of future architects and civil engineers, we solve applied problems with students, perform professionally - oriented tasks and projects. Any design solutions in architecture and construction should be mathematically justified. Therefore, any architect, civil engineer should know the theoretical foundations of mathematics, be able to build mathematical models, solve applied problems using the methods of mathematical statistics for processing experimental data.
Development and Research of Properties Cement Concrete Hardening Accelerator Additive Based on a Mixture of Inorganic Fluorine-Containing Salts
Authors: Roumyantseva V Eu , Goglev I N , Loginova S A , Truntov P S , Burkov A A
Published: March 2020

the article describes the basic salts and their mixtures used to accelerate the hardening process of cement concretes in the practice of modern construction. Development and main characteristics of the additive accelerating process of hardening of cement concrete are presented. This additive is based on a mixture of non-organic fluorinated salts. The composition of the additive allows to accelerate the process of hardening of cement stone, due to the formation of insoluble and dense compounds. A number of experiments were carried out to determine the optimal amount of fluoride salts in the additive. The results of the research showed a low consumption of additive per 1 m3 of heavy concrete. Advantages and disadvantages of the additive allow us to recommend its use to accelerate the hardening of concrete in a wet environment. The article provides a detailed description of the test methods. The tests were carried out using certified and verified measuring instruments taking into account the strength characteristics of the materials. As a result, the dependence of the concrete hardening rate on the amount of additive used was revealed. The article also discusses some proposals for the practical use of additive in the production technology of concrete and reinforced concrete. According to the results of destructive and non-destructive testing, an increase in the strength of concrete by >30% compared to conventional concrete.
Sound-Absorbing Polymer Composite Materials for Construction Purposes
Authors: Nigmatullina A I , Galimzyanova R Yu , Khakimullin Yu N , Stytsenkov A A
Published: March 2020

The paper presents the results of a study of the influence of the nature fillers (wood flour, wood dust, vermiculite, expanded vermiculite, organoclay) and a polymer matrix (elastomer and thermoplastic) on the sound-absorbing and physico-mechanical characteristics of polymer composite materials. As a result of the studies, it was shown that sound absorption depends on the polymer matrix used - the sound absorption coefficient in the frequency range 2500-5000 Hz is greater for an elastomer-based composite material. It was also found that the nature of the studied fillers, as well as their content, practically does not affect the level of sound absorption of the polymer composite material. Differences appear only at a frequency of 6300 Hz. At high frequencies, expanded vermiculite has shown itself to be the most effective filler in terms of improving sound insulation properties. In the case of using, as a polymer-based thermoplastic, the introduction of a filler does not affect the values of the sound absorption coefficient in the entire frequency range.
Modeling and Optimization of a Mechanical Point Connection with the Reinforcement of Structures Containing Polymer Composite Materials
Authors: Vashukov Yu A
Published: March 2020

The methodology of determination of geometric parameters of the reinforcing element in case of highly resourceful mechanical point joint formation in the products of anisotropic polymer composite material (PCM) is presented. Physical-mechanical properties and the safety factor of the composite material are also taken into account as well as the material of the reinforcing element. The developed methodology applying finite-element modelling allows to analyze the strained state of the reinforced element and to determine optimal parameters of its mounting.
Solving Air Conditioning Problems in a Design Project Using Energy-Efficient Daylighting Systems Based on Hollow Tubular Light Guides
Authors: Pleshkov S , Bracale G , Ibragimov I , Vedishcheva I
Published: March 2020

In our work we demonstrate a developed design project for lighting a 24-hour cafe at one of the largest airports in Russia. The project is based on use of energy-efficient technology for delivering natural light to rooms with constant presence of people. The existing option includes only minor artificial lighting. Employees and passengers who, for various reasons, have to stay in the terminal cafe for a long time, experience certain discomfort and fatigue for lack of natural light and continuous air conditioning in summer time. The proposed design project allows not only to radically change the interior atmosphere of the cafe due to natural sunlight and diffuse light, but also significantly save energy costs associated with continuous round-the-clock energy consuming artificial lighting and air conditioning in summer, contribute to improving the psychological comfort of people and preserving the natural environment. This statement is confirmed in this article below by the heat engineering calculation performed in Ansys calculation complex. There are no analogues to this project. Illumination calculations were performed in improved DIALux program, into which the relevant information on the applied daylighting systems was integrated. The calculation of the economic profitability of the design project confirms feasibility of material costs.
Changes of the Energy Intensity of Destruction of Autoclaved Aerated Concrete during Compression with Changes in Its Physical Parameters
Authors: Kshnyakin A , Kovalchuk A , Tsuprik V
Published: March 2020

Conventional in mechanics of material fracture failure criteria GiC and CS based on Griffith’s energy concept about development of a fracture. These criteria postulate fact of occurrence the limiting state in the material around the tip of the crack occurs when the rate of elastic energy growth and the rate of its absorption in the bounded zone are equal. For complex composite materials such as concrete, the possibility of applying these criteria remains controversial due to the pronounced heterogeneity of this type of materials, in which the size of the individual rigid elements of the structure is commensurate with the size of the test samples. But the energy nature of destruction is fair and obvious in any materials, so for them there must be an energy criterion of destruction, which not only States the fact of destruction, but also integrally takes into account the expenditure of deformation energy not only on elastic but also on plastic processes, including thermal. The proposed effective specific energy of destruction of the material as a criterion of destruction should take into account all the features of destruction not as a fait accompli, but as a process of accumulation and dissipation of energy in the deformable volume, and not at the tip of a single crack. The article describes a method for obtaining the effective energy density of the destruction and presents results of a study of this magnitude for one of the types of concrete – autoclaved aerated concrete, given that this relatively homogeneous material is the most suitable for pioneering research is relatively new strength parameter for materials with complex structures. To determine the range of possible values of the investigated value, a factorial experiment was performed with variation of such factors as: density, loading speed and water saturation of cellular concrete. The type of dependence of energy consumption of a cubic sample in time from various factors causes the mechanism of destruction of this material – viscous or brittle and describes the process of accumulation of defects in the process of increasing elastic deformation to the moment of destruction.
The influence of the Content and Dispersity of Aluminum Hydroxide on the Properties of Siloxane Sealants
Authors: Kurbangaleeva A R , Khakimullin Yu N , Volfson S I , Gadelshin R N , Ponomarev P V
Published: March 2020

The influence of the content of aluminum hydroxide of various degree of dispersion on the rheological, physical-mechanical and adhesive properties, thermal and fire resistance of siloxane sealants was studied. It was established that the main factor determining the effectiveness of the use of aluminum hydroxide in siloxane sealants is the degree of dispersion. The introduction of aluminum hydroxide makes it possible to vary widely the viscosity of the sealant compositions, while with decreasing of particle size of aluminum hydroxide the viscosity of the compositions increases. The use of aluminum hydroxide with a minimum particle size makes it possible to obtain siloxane sealants with the most optimal level of physical-mechanical and adhesive properties, however, to increase the thermal and fire resistance of sealants, coarse aluminum hydroxide is most preferred.
The Use of Larch Wood in Composite Wood Elements on Inclined Screwed Rods
Authors: Linkov V I
Published: March 2020

The article discusses the use of larch wood in wooden elements of a composite section on pliable bonds in the form of oblique metal rods (IRS compounds). The test results of samples of IRS compounds from larch wood on inclined screwed rods are presented. The upper boundary of the region of elastic work of IRS compounds from larch wood and deformation of compounds are determined. A comparative assessment of the bearing capacity and deformability of IRS compounds on screwed rods made of pine wooden elements and larch wood is performed. Based on the test results of compounds, the calculations of bending elements of a composite section with a span of 6 m were performed using the theory of composite rods by A. R. Rzhanitsyn. The effectiveness of the use of larch wood in supporting structures made of solid wood is shown.
The Choice of Organizational and Technological Solutions Based on the Modeling Option
Authors: Shatrova A
Published: March 2020

The construction industry in Russia, whose activity affects the economic development of the country’s economy, is changing. This is expressed in the development of new laws, building codes, rules and relevant organizational and technological solutions at the level of construction production.

In this regard, construction production needs to improve organizational and technological solutions, taking into account modern regulatory requirements and production conditions. The selection of traditional methods for updating these decisions is an urgent task that requires proper research.

The analysis of organizational and technological decisions of the organization and technology of construction production showed that organizational models of construction production need to be refined and optimized in accordance with the new realities that the participants in the construction industry have encountered.

This primarily concerns construction organizations operating in conditions of destabilizing production factors.

Construction managers, including engineers and technicians, need to pay close attention to organizational and technological solutions at various stages of the implementation of an investment construction project, especially when drawing up a work schedule.

An important task when using the theory of experimental design is the selection of factors and the determination of their influence (values) during the experiment.

In this regard, the author conducted research to plan and conduct theoretical experiments based on the method of expert survey. Also, given the totality of factors that are random in nature and affect the result, the object for research described in the article (construction production) is considered in the form of a black box cybernetic system.

Research conducted by the author will allow:

- prevent the emergence of destabilizing factors in the construction industry;

- improve the effective functioning of the construction industry;

- elimination of the risk of construction in progress.

The final choice of organizational and technological solutions based on variant modeling using simulation and other methods will improve the quality of technical and economic indicators of both construction production and the investment project as a whole.
Model Pilot Study Statement of Filled Shells Constructions under Dynamic Impact
Authors: Tsimbelman N Ya , Shalaia T E , Chernova T I
Published: March 2020

Formerly uninhabitable Russian territories at earthquake risk are appropriated for exploitation while ancillary development of necessities of life. In this regard, new facilities construction and existing facilities reconstruction in the field of transport, energy industry and other sectors are expected. Combined constructions (e.g. – soil-filled shells) have been increasingly used in construction. Above-mentioned constructions scope of use is potentially wide and if properly estimated they could adequately meet necessary requirements. Nowadays there is an insufficient discussion of construction interaction with the bulk filler and ground foundation, which results in current calculation methodology not covering significant areas of baseline estimate. Thus, the problems of stress-stain state study of these constructions under the dynamic impact remains relevant.
Physical Modelling of the Corona Discharge Effect on the Casting in the Mold
Authors: Ogloblin G V , Ankudinova M A
Published: March 2020

In this article we describe the technique and the methods of physical modelling of the corona discharge usage in order to harden the material. The active substance in the detector is the liquid crystals of a cholesteric type with a mesophase of 40-45 C. The substrate of the detector is a cast of aluminum alloy with specified parameters in the form of a rectangular or round shape. A corona discharge is created with the help of high-voltage power source (e.g. «Разряд») when the voltage is applied to a pair of needle-plane electrodes. The modulation of the ultrasonic signal is carried out through the inductive coupling. The parameters of the corona discharge are calculated with accordance to the received samples and temperature patterns. An assessment of the effect of a corona discharge on a liquid metal is determined by the Brinell scale displaying the indentation hardness.
Construction Sealants Based on EPDM Modified with Silane-Terminated Urethane Prepolymers
Authors: Murtazina L I , Akhmedgoraeva A R , Galimzyanova R Yu , Khakimullin Yu N
Published: March 2020

In connection with the use of new materials and structures in construction, the issue of developing sealing materials for construction purposes with an improved set of properties remains relevant. In particular, sealing materials based on ethylene propylene diene rubber (EPDM) are promising due to their resistance to UV radiation, ozone, and the absence of cold flow. The paper shows the possibility of obtaining reactive sealants based on EPDM and silane-terminated prepolymers - STP based on oligotetraoxymethylene glycol (polyfurite) and based on oligooxypropylene glycol (laprol). The use of prepolymers leads to an increase in the cohesive and adhesive strength of the sealing compositions, while maintaining the cohesive nature of the fracture. Also, the obtained sealants are more technological, since they have a lower viscosity under processing conditions. Extensive tests of reactive sealants based on EPDM have shown that after aging it has a higher level of properties compared to sealants without STP.
Life Environmental Assessment of Housing Safety as a Necessary Condition for Technosphere Human Security
Authors: Glebov V V , Rodionova O M , Erofeeva V V , Anikina E V , Mikhaylichenko R Yu , Solovev D B
Published: March 2020

The paper gives an environmental assessment of frequently used building materials, which are widely used in the construction of modern houses and apartments. The data of chemical composition of building materials, their fire danger, toxicity and quality, as well as the level of threat and danger to human health living in such apartments and houses are presented. Recommendations are given to improve the quality of life of people to improve the overall technosphere human security.