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Introduction. The processes of structure formation of cement compositions and the development of effective technologies of building materials is an urgent task for building material science. The use of large-scale man-made product of pulp and paper enterprises – osprey as a fibrous filler in organic and mineral compositions is the successful decision of the problem. The paper analyzes the ways of using osprey in the building materials’ production. The aim of the research is to study the osprey influence on the processes of structure formation of cement stone by quantitative x-ray phase analysis.Materials and methods. The organic and mineral compositions were obtained on the basis of portland cement and osprey. The authors studied the compositions’ phase of osprey, portland cement and the processes of cement stone structure formation in organ and mineral compositions by quantitative x-ray phase analysis.Results. The authors determined the compositions’ phase of mineral impurities of osprey, cellulose, cement, cement stone, organic and mineral compositions and two compositions containing 25 and 75% by weight.Discussion and conclusions. The osprey application as a filler in the organic and mineral composition causes inhibition of processes of cement hydration. The presence of osprey in the hardening organic and mineral composition leads to a change in the composition and structure of the cement stone in comparison with the phase composition of the cement stone without additives. The result of these changes is a significant increase in the amount of calcite, waterite and a significant decrease in the amount of portland. The authors establish that the effective joint work of the reinforcing component of the osprey with the cement matrix is possible with a limited amount of osprey in organic and mineral compositions.

Introduction. This paper presents the results of a study on the methods for calculating the capacity of level crossings. The purpose of writing this research paper is determine the best methodology for calculating the intervals in the main flows for the prevailing road conditions in the Russian Federation, that a new methodology to calculate capacity adapted to domestic road conditions would be developed in the future.Materials and methods. In recent decades of market relations in the Russian Federation, one can note a rapid increase in motorization in human settlements. The number in 550 vehicles per 1000 people in domestic entities is expected to have been increasde by 2025, which is significantly higher than the current level in European part of the Russian Federation. It is important to note that when the number of vehiclec is increasing, which level is about 80%, it is essential to increase road crossings capacity. Results. At the moment the methodology for calculating capacity and queue length is the same. It should be noted that the current models are not properly described in the domestic studies, but the calculations were made using models developed in the 1960s and 1970s.

Introduction. The process of shifting gears under load is one of the most complex types of dynamic process in the transmissions of transport, road and construction vehicles. Currently, the existing calculation methods do not fully reflect the features of the engine and automated gearbox interaction by switching stages under load using more than two friction clutches at the same time. The paper discusses the method of calculating the dynamic characteristics of the gearbox with the simultaneous use of both two and four friction clutches by shifting gears under load with forward and reverse switching. The authors present the results of the dynamic characteristics of the theoretical study of the automated gearbox with frictional stages’ switching under load and without breaking the power flow.Materials and methods. The main method was based on a system approach to the dynamic processes study and on the modeling of the gearbox operation together with the internal combustion engine. The authors took into account the regulatory, speed and load engine characteristics, resistive torque variation, rate of pressure rise in clutches by shifting to higher and lower gears. The paper performed theoretical modeling of processes using the MATLab package and the Simulink application. Using the main blocks of this application, the authors created models of physical components: an internal combustion engine, friction clutches, gear reducers, elastic shafts, damping devices and tractor power transmission control systems.Results. As a result, the authors obtained calculated data of the dynamic processes, variations in speed and rotational torque on the gearbox shafts; the load on the engine by shifting gears at different values of the start and finish time in switching on and off the gearbox friction controls. The paper presented the relevant graphs of the processes.Discussion and conclusions. The developed method of calculating the dynamic characteristics of the gearbox allows simulating workflows by shifting to higher and lower gears. This method takes into account both the parameters of the gearbox design and of the control actions: the rate of switching on the friction clutches; the time intervals of overlapping the “on and off” clutches. Therefore, in relation to the considered gearbox, the authors determine the values of the optimal time control commands of the friction by shifting.Financial transparency: the authors have no financial interest in the presented materials or methods. There is no conflict of interest.

Introduction. The paper devotes to the features of hydration and hardening of polymineral composite binders. The authors carry out the complex research of the phase composition, hydration and structure formation processes of hardened composite binders with active mineral additives by X-ray phase analysis, differential scanning calorimetry and electron microscopy. The study using a Tescan MIRA 3 scanning electron microscope reveals differences in the microstructure of hardened binders and the authors confirm the results by microprobe studies. The authors study the hydration of the composite binder prepared on the basis of Portland cement and mineral components. Moreover, the paper demonstrates the dynamics of the system’s heat dissipation from the moment of mixing with water and hardening up to 24 hours and up to 72 hours by the expressed bond of dQ / dt = f (t) using a differential calorimeter.Methods and materials. The authors carried out experimental studies at Belgorod State Technological University named after V.G. Shukhov, at the Department of Building Materials, Products and Structures, at the High Technology Center and “BelGTASM-Certificate” Test Center. Therefore, the authors used the existing basic research methods, including modern physicochemical methods of analysis: X-ray phase, scanning electron microscopy, etc. The paper determined the main characteristics of raw materials, composite binders and foam concrete using standard methods and regulatory requirements.Results. The authors obtained the results that testified the peculiarities of hydration and hardening processes of polymineral composite binders on the basis of Portland cement and mineral additives: opoka marl and fly ash.Conclusion. The research establishes the hydration and hardening processes of polymineral composite binders. As a result, the authors demonstrate that the opoka marl introduced into the cement leads to the increased hydration in the induction and accelerated periods and also increases the hydration completeness of the main clinker minerals due to the manifestation of the pozzolanic reaction and the active binding of blocking Portlandite, as well as to the higher concentration of accumulated neoplasms, second generation calcium hydrosilicates.Financial transparency: the authors have no financial interest in the presented materials or methods. There is no conflict of interest.

Introduction.The paper deals with traffic light regulation. This task is always relevant. Thus, even for an ordinary intersection, depending on the intensity of traffic flows, the control cycles should differ significantly. This paper discusses all kinds of systems, namely, two-phase, three-phase, four-phase and others. In addition to solving optimization problems of regulation the authors propose to use the device managed network, which allows setting the configuration of the transport network as the base graph of the managed network, and then based on the parameterization of the graph of the throughput ability of the network to solve the optimization problem of selecting the control traffic and pedestrian flow.Methods and materials. For solving the problem of traffic management on the road network, the authors proposed to use the mechanisms of managed networks. As a result, the authors presented a technique based on the calculation of saturation flows, the main characteristic of the control technique, which was activated when there were no requests from the transport detectors to turn by the green signal.Results.The authors constructed a generalized simulation model of control phases of regulation based on the usage of controlled networks, depending on the intensity of traffic flows and formed a method of selecting modes of traffic lights for different traffic situations.Discussion and conclusions.The solution of the problem of traffic light regulation significantly affects the traffic management efficiency. The authors determine the main parameters based on the analysis of traffic light control methods. As a result of the calculation of the saturation flow and information about the intensity of traffic, the authors form the method of selecting the necessary modes of the phosphor object’s operation.The authors have read and approved the final manuscript. Financial transparency: the authors have no financial interest in the presented materials or methods. There is no conflict of interest.

Introduction. Hole details are quite widely used in structures of construction and road machines. The specialists apply boring for draft, semi-fair, and in some cases for fair processing of such surfaces. This type of processing is often followed by the negative nature of oscillatory processes that leads to decrease in accuracy and in the surface quality. The paper studies the possibility of the calculation method’s usage in oscillatory processes, which allows assigning the cutting modes by providing required output parameters.Materials and methods. The authors used the double-support beam as a design model of a boring cutter. The solution of the fluctuations’ modeling came down to definition of point movements, which corresponded to cutter top (points of application equally effective cutting forces). The authors made the definition of movements with use of Mor integrals. Therefore, the paper considered the impact of chip formation and separation due to perturbing forces.Results. The authors carried out the calculation of forces’ values in cutting with use of the degree dependences. Moreover, the authors accepted the formation’s frequency as the frequency of the perturbing influenced structure. The frequency of the chip formation was defined on the basis of estimated dependences, which connected parameters of the tool, the cut-off layer and modes of cutting. As a result, the author received the implementations of oscillatory processes and studied the influence of different factors on vibration amplitude.Discussion and conclusions. The authors make assessment of the received results’ adequacy by comparison with experimental data. The error doesn’t exceed 20%. The developed model considers geometrical parameters of the tool (a departure, plate corners, etc.), the modes of cutting both mechanical properties of the processed material and parameters of the chip formation. The model can be used both at design of boring operations and by optimization of the cutting modes for the purpose of productivity increase.

Introduction.Since the second half of the 20th century the safety in the automotive industry has been bringing to the forefront. Therefore, researches pay special attention to stability and controllability. These properties increase in a variety of ways, one of which is using of the four-wheel steering system (4WS). Foreign literature presents technical solutions on the example of sport cars and some Japanese models.Materials and methods.The paper provided an analysis of the four-wheeled steering passenger car’s kinematics. The authors considered the turning geometry with positive and negative steering angles of rear axle, on the basis of which the researches proposed calculation formulas for determining the turning radius of the car and the angles of the wheels’ rotation. The kinematic relations used in designing a steering system with four steered wheels.Results.The authors on the example of Volkswagen Polo calculated the turning radius and controllability depending on the steering wheels’ angles of the front and rear axles. As a result, the paper demonstrated the change in parameters and the effect on the safety and handling of the vehicle. The authors also highlighted the advantages of using a four-wheeled steering system.

Introduction. The paper deals with the results of the reliability of urban public passenger transport routes. One of the main objectives is to consider the indicators for assessing the reliability of the urban passenger transport system, which have not yet been used in Russian practice. The peculiarity of these indicators is that the initial information can be obtained on the basis of modern bus equipment (GLONASS/GPS). The possibility of using these indicators, as well as the development of scales of reliability levels at the moment is an important scientific problem.Materials and methods. The authors proposed modern indicators for assessing the reliability of urban passenger transport routes, such as the time index and the associated buffer time indicator. The authors used the methods of mathematical statistics to process the data on the duration of bus traffic.Results. The authors obtained the reliability characteristics of urban passenger routes. Moreover, the paper presented the comparison of the reliability values on the example of Irkutsk and Angarsk.Discussion and conclusions. The authors reveal the range of values of the time and buffer indices based on the data of route networks of two different cities. Therefore, the authors offer the estimation scale of the reliability levels on routes.

Introduction.Construction of engineering structures is impossible without building and road machines. The large volume of financing is allocated for such machines’ purchase. The main ways of reducing costs of the equipment consist in more rational operation of the equipment and also in decrease of equipment’s cost by constructive changes. The paper demonstrates the new design of the single-bucket hydraulic excavator with smaller cost.Materials and methods.The main ways of cost reduction for construction machines are more rational operation and depreciation of a design with the required characteristics’ maintaining. The paper describes constructive changes of the working equipment of the single-bucket hydraulic excavator, which allow decreasing the production costs.Results.The authors describe the new bucket design of the single-bucket hydraulic excavator. Moreover, the authors carry out the analysis of the existing buckets’ design. The paper also illustrates the functioning on bucket forces while digging process. The authors describe the solutions of the problem for productivity increase of the single-bucket in hydraulic excavators. In addition, the authors make the scheme of the bucket loading while digging process. Such scheme helps to reduce resistance forces of digging.Discussion and conclusions.As a result, the paper presents the design of the working equipment of the hydraulic excavator’s single-bucket, which allows reducing resistance forces of digging. Such results would help to establish buckets of bigger capacity and would lead to the productivity increase.

Introduction. The article is devoted to a current issue of improving the quality of road surface cleaning and increasing the resource of brush working equipment. Improving the quality of cleaning and the resource of the brush working equipment will reduce the cost of operating a communal machine. In the process of operation, the pile of the cylindrical brush is worns out, while its elastic characteristics change, which is reflected in the required pressing force to maintain the most favorable value of the width of the contact spot from the condition of ensuring high quality cleaning and minimal intensity of pile wear.Materials and methods. The results of studies of the interaction of the pile of a cylindrical brush with the surface to be cleaned are presented at various degrees of wear of the brush pile. The research results are presented in analytical and graphical forms. The calculations were carried out using the Microsoft Excel software product and the Mathkad software environment for mathematical calculations.Results. The paper shows the dependence of the degree of wear of the pile of the brush working equipment on the actual radius of the cylindrical brush. The relationship between the width of the contact spot and the deformation of the cylindrical brush at different degrees of wear and tear is shown as a graph.The influence of the degree of wear on the elastic characteristics of the brush working equipment is considered. The dependences of the average stiffness coefficient on the degree of wear of the pile of a cylindrical brush, as well as the required pressing force on the degree of wear at different values of the width of the contact patch of the cylindrical brush are given.

Introduction. One of the main elements of the safe operation of gravity roller conveyors used in pallet racks is a brake roller. The most promising design is the brake roller magnetic (eddy current) type. The operation principle of such rollers is based on the laws of electromagnetic induction and involves the braking of a conductor moving in a magnetic field, due to the interaction of eddy currents (or Foucault currents) arising in the volume of the conductor with an external magnetic field. However, in the market of warehouse shelving equipment, brake magnetic rollers are not widely used due to their high cost, which is primarily due to the lack of domestic designs and methods for their calculation. The aim of the work is to develop a mathematical model of the moving pallets process on a magnetic type brake roller.Materials and methods. The paper presented the theoretical study results on the development of a mathematical model of the moving pallets process on a magnetic type brake roller, described in works on centrifugal friction rollers and eddy current brake devices.Results. The main parameter determining the functions of the brake magnetic roller and hence the speed of the pallet along the gravity roller conveyor is a magnetic viscosity coefficient. The speed dependence of the pallets on the brake magnetic roller for various values of a magnetic viscosity coefficient is determined, its analysis is carried out.Conclusions. A mathematical model of the moving pallets process on a brake magnetic roller is developed. The movement speed equation of the pallets on the brake magnetic roller is obtained. For a reasonable choice of the design parameters of the magnetic brake roller, experimental studies are required to determine a magnetic viscosity coefficient.

Introduction.The problem of increasing the efficiency of power machines is important to develop a new design of the main elements or drive with the possibility of widespread use of hybrid drives. To preserve the power characteristics of the drive and its technical and operational indicators, the authors consider a hybrid with the available electric and hydraulic drive parts that form a complex synergistic mechanism as an alternative. The proposed combined tracking system with the specified parameters allows for the efficient operation of the drive of many machines.Materials and methods.The paper presented the results of an analytical study, the prospects for the development of mechatronic systems in engineering and technological complexes. The research also identified the industry area with a high development potential for mechatronic and hybrid drives. The authors formulated the problem of designing and developing hybrid drives due to the fact that there was no single method for substantiating the energy efficiency indicators of a power hybrid drive that ensured the interaction of two dissimilar systems (electric drive and hydraulic drive with fundamentally different parameters).Results. Therefore, the authors conducted the analysis of the structural, technological and operational parameters of the hybrid drive systems and proposed a combined servo drive system.Discussion and conclusions. The authors prove and justify the extensive possibilities of using hybrid drives as an alternative to pneumatic and hydraulic drives The results of the research allow specifying the directions and prospects of using hybrid synergetic drives and systems for the functioning of working equipment, machines and complexes.Financial transparency: the authors have no financial interest in the presented materials or methods. There is no conflict of interest.

Introduction. Rubber bushings are important parts of the spring systems of modern vehicles. The properties determine not only the comfort of car movement, but also affect the elastic suspension characteristics. When a bushing is deformed, linear sections appear in characteristics. It is advisable to describe such characteristics using a mathematical model based on the classical elements of Hooke and Saint-Venant. The paper presents a mathematical description of the bushing simulation functioning results, accuracy of approach, areas of application of the mathematical model.Materials and methods. The initial data was the experimental characteristic of a cylindrical automobile rubber bushing, obtained in harmonic mode at the 0.03 to 51 Hz frequency and the 0.4 to 10 mm amplitude. The force balance of the two Hooke elements and one Saint-Venant element interacting with each other determined the mathematical model description. The authors carried out the calculations using numerical and optimization methods.Results. As a result, the authors determined functions characterizing the change in the parameters of the Hooke and Saint-Venant elements from the rubber bushings’ deformation amplitude. Moreover, the authors calculated power characteristics in the form of dependences of the rubber bushing effort and also found quantitative indicators of the reliability of the experimental data approximation by the developed mathematical model.Discussion and conclusions. The analysis of the operating modes shows the possibility of the model application to describe the rubber bushing functioning in a stationary harmonic mode with small and medium strain amplitudes. The simulation results of the Hooke’s and Saint-Venant’s parameters reveals the theoretical prerequisites for the possibility of using the model to calculate the bushing force in an unsteady mode.The authors have read and approved the final manuscript. Financial transparency: the authors have no financial interest in the presented materials or methods. There is no conflict of interest.

Introduction. An analysis of the most well-known agglomeration management models in Russia and abroad has shown that there are no comprehensive solutions in this area yet. The problem of information modeling of control actions on the state and development of the road network of these territorial entities is not well understood and requires further comprehensive research. The purpose of the paper is to formulate the most important principles and methodological approaches for building a modern information system for managing the road infrastructure of urban agglomerations.Methods and models. The designed system based on information modeling technologies of transport interaction processes between corresponding points. The structure of the system presented on the principles of multi-agent project management. The authors identified the types of mathematical models for solving key problems in the framework of design modules by creation of an agglomeration transport framework, ensuring the regulatory requirements of the transport and operational condition of roads and by creation of conditions for the continuous and safe movement of road transport.Results. The architecture of the “Road Network-6D BIM” developed system reflected the relations of two information processes: filling the system with knowledge and forming box solutions using a knowledge bank. The n-D modeling based on three-dimensional projections of structures (3-D) with the addition of digital modeling technologies: calendar terms, resources and financing of objects in the life cycle. The authors tested system elements during the experiment and the implementation of the project for the integrated development of the transport infrastructure of the Omsk agglomeration.Discussion and conclusions. The implementation of the “Road Network-6D BIM” project in the proposed concept makes a definite contribution to solving the problems of managing the road network of the city agglomeration by increasing the level of intellectualization of the tasks at all stages of project management.

Introduction. The paper presents the results of research that allow assessing the degree of influence of pre-organized cracks on the character crack formation and on the process of the hollow-core slabs’ deformation under short-term load action.Materials and methods. The hollow-core slabs are made without prestressing – one by traditional technology, the second with pre-organized cracks in the manufacturing process. Physical experiment performed on fall-scale structure of hollow-core slabs of П66.10-81500СП. The authors conducted the tests to the calculated breaking load. Moreover, the authors presented the contrastive analysis of character crack formation and of the hollow-core slabs’ deformation of П66.10-8А500СП traditional manufacturing and with pre-organized cracks.Results. As a result, the authors confirmed the earlier hypotheses about the greater rigidity of plates with pre-organized cracks in comparison with the plates where the cracks arose stochastically and under operational load. The installation of organized cracks did not reduce the bearing capacity, thus, reduced the deformability. Therefore, the width of the crack became smaller and the deflections became less.Discussion and conclusions. In the structures of long length, which are rejected by the second limit group, the organization of cracks at the manufacturing stage allows not putting additional reinforcement to reduce the width and deflection of the crack.

Introduction. The objective of the research is to study the effect of the complex activation of the alumina raw material on the rheological properties of the ceramic mass. In addition, the authors investigate solutions for the application of optimal coagulation structures based on loams and ash together with plastic certificates.Materials and methods. The authors used the local forest like reserves of clay loams at the BashKarasu, ash fields of the Bishkek Central Heating Centre (BTEC) and plasticizer (sodium naphthenate obtained from alkaline chemical production wastes) as fibrous materials. Moreover, the authors defined technological properties of raw materials within standard laboratory methodology in accordance with current GOSTs.Results. The researchers tested plastic durability on variously prepared masses for the choice of optimal structures. The paper demonstrated the plastic durability of complexly activated compounds comparing with non-activated and mechanically activated compounds. The sensitivity coefficient increased the amount of clay loams by mechanically and complexly activated, which predetermined the possibility of intensifying the process of drying samples based on complexly activated masses.Discussion and conclusions. However, mechanical activation of clay material reduces the period of relaxation and increases the elasticity coefficient of ceramic masses by 1.8–3.4 times, meanwhile decreases elasticity, viscosity and the conventional power during molding, which generally worsens the molding properties of the masses. Сomplex activation of ash-clay material decreases the period of relaxation and provides an increase in elasticity, plasticity of ceramic masses by 46–47%, reduction in viscosity by 1.5–2 times, conventional power on molding by 37–122% in comparison with MA clay loams. Ceramic masses based on spacecraft alumina raw materials belong to the SMT with improved rheological properties; products based on them pass through the mouthpiece for 5–7 seconds.

Introduction. The paper substantiates the relevance of the development of regional transport strategies, which are basic for the implementation of organizational, technical and economic solutions aimed at the reorganization of modern urban and regional transport systems. Moreover, it is indicated that the development of strategies should be accompanied by a comprehensive and coordinated survey and modeling of transport systems, including within the framework of the regional programs of integrated development of transport infrastructure, projects for the creation of integrated traffic management schemes, as well as integrated schemes of transport services to the population. The aim of the research is to formulate the tasks consisting the proposals at the coordination of all the above and other programs that ensure long-term planning, continuity of decisions and budget savings directed to the development of transport in the regions.Materials and methods. Methods of system analysis, theory of transport systems, as well as methods that are widely used in the community of transport engineers, including various options for calculation and experimental methods of transport planning and modeling of transport systems for the city or agglomeration, are used to solve the research problems.Results. Based on the information synthesis of the stages of regional transport strategies development, a sequence of actions is proposed, leading to the required methodological and organizational approaches, with which it is possible to perform the solution of the strategic task. The authors formulate a list of major programs that need to be addressed at the level of regional ministries (departments) or departments of transportation municipalities with the goal of implementing transport strategies and aligning them with projects noted above. Discussion and conclusions. The main result of this work is the conclusion about the feasibility of rational actions of regional and municipal transport governing bodies, which could be planned within the framework of regional (municipal) transport strategies. The basis is the application of the proposed methodological and organizational recommendations.