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The article considers the dynamic processes of the oscillatory system «wagon - way», its mathematical model is formed and its features are established. The analysis of existing approaches to the consideration of the influence of dissipative forces on the stability of rolling stock is carried out, their shortcomings are revealed. When composing dynamic process equations, it is important to proceed from their exact expressions when considering kinetic and potential energy, i.e. to take into account the relationship between generalized coordinates, which will allow us to consider in detail the process of rolling stock oscillations. The zone of autoparametric resonance is found. It is established that dry friction forces do not interfere with parametric resonance. Dynamic equations are compiled taking into account the scattering forces arising in the contact points of the structural elements of the car. The influence of dry friction forces on the critical coefficient of parametric excitation is determined. The areas of dynamic instability of a car when moving along a railway track with different characteristics are determined. The features of the behavior of the system under the influence of dry friction forces are revealed. It is established that dry friction forces do not reduce the amplitude of bouncing and can lead to an increase in lateral pitching vibrations due to energy pumping.

The possibilities of improving speed and reducing the time of passenger trains on the Trans-Siberian railway, including through new passenger locomotives EP1, EP2K, EP20.

Considered the features of modern automatic control systems of pantographs. The spectral density analysis of pantograph contact force at high speeds showed requirements for robust control systems, which allows to significantly improve the quality of the current collection. Proposed the ways to improve the automatic control systems for pantographs, aimed at improving the speed and reducing the inertia of the system.

The article considers phenomenological and modelling approach to researching of interaction of a deformable wheel and a plane of support, their advantages and disadvantages are mentioned. In the context of phenomenological approach the five methods of locomotive tangent tractive force calculation were considered. There certainly must be pseudo-creeping to let locomotive tangent tractive force do work and change the kinetic energy of a train in the point of wheel and rail contact. Locomotive tractive force experts calculate the power as product of the locomotive tangent tractive force and the velocity of translational motion of a train, although in fact the velocity of the point of force application must be assumed. It is applied to a wheel pair, then the velocity of this point must be used to calculate the locomotive power. According to this fact the locomotive power is found several tens of times reduced.

The article noted the need to improve the technology of repair locomotive wheelsets. We propose a model describing the process of machining tread on milling machines based on thermo-mechanical approach to cutting metal. On the basis of the model is a method for analytical determination of the forces of milling, the temperature front and rear surfaces of the carbides. Presented results of the comparison of experimental data and data obtained analytically.

To increase the speed of the cargo delivery, freight wagons are being developed, intended for the design speed of 140 km/h. One of the important parts of a freight wagon is the bogie, the design of which determines the wagon dynamic behaviour. The bogie of such wagons uses a frame of a rigid design, which is susceptible to antisymmetric loads. The analysis of standards has shown that the strength test during designing a rigid bogie frame under the impact of maximum antisymmetric forces that may occur in operation when a wheel derails is not required, which can lead to a residual antysymmetric deformation of the bogie frame. Theoretical research is performed to estimate the impact of the residual antisymmetric deformation on traffic safety using the wheelset safety factor against derailment. The research results have shown that the bogie frame residual deformation leads to a load redistribution on the wheelset axle journal, which, in terms of the impact on the wheelset safety factor against derailment, is similar to the wagon rolling motion. The wagon rolling motion affects the reduction of the wheelset safety factor against derailment to a greater extent than oscillations during pitching and bouncing. Thus, the permission to operate wagons with the antisymmetric residual deformation of the bogie frame without its non-destructive testing can lead to traffic safety violation. In order to ensure the traffic safety of wagons with bogies having rigid frames and reduce economic losses at the design stage, bogies strength depending on the action of antisymmetric forces should be estimated.

One of the properties of the reliability of the power supply of electric rolling stock of railways is the trouble-free operation of the traction power supply system in various modes of its operation. For post-emergency and forced modes of operation of the traction power supply system, a decrease in load capacity is characteristic. In order to ensure the throughput and carrying capacity of the railway section by traction power supply devices, it is proposed to consider the use of electric power storage devices on electric rolling stock and in the traction power supply system. Studies conducted by domestic and foreign researchers allow us to evaluate the effectiveness of alternative solutions to improve the reliability of power supply, which include various options for the use of electric power storage devices on electric rolling stock and in the traction power supply system. This article presents the results of a review of these solutions, a simulation model of a traction power supply system and an electric rolling stock with power storage devices based on various batteries and a supercapacitor is proposed. Modeling of changes in the modes of operation of the traction power supply system is carried out taking into account the state control of switching devices. The calculation results allow us to estimate the voltage drop at the output of electric power storage devices, including taking into account the exponential zone of the discharge characteristics of batteries, to estimate the voltage change for a given electric traction load depending on the energy intensity of the storage device, made on the basis of the most common types of batteries and a supercapacitor.

Results of mathematical modeling of determination of character and the law of change of forces and tension arising in the field of contact of interacting bodies on the example of dynamic contact at impact of an elastic sphere about motionless, absolutely rigid plate are presented in article, at its flat movement. The received results can be used at calculations of contact forces and material tension in a metalwork at shock influences.

This article contains results of experimental studies on the formation of corrosion products as a result of aggressive environment and electric currents action on the reinforced concrete structures. There are discussed a method of creating models with artificial electrocorrosion under conditions close to real working. The results of testing models using the X-ray method and modeling their strength characteristics are presented.

In article aerodynamic properties of SSS87 current collectors intended for the high-speed movement of the electric rolling stock are considered. Spectra are presented of the flow for different shapes of the contact plates. The solution of a problem of modeling of flow of the contact plates of the current collector with the air environment is reached by application of methods of computing hydrodynamics (CFD) the aerodynamic coefficients necessary for calculation of aerodynamic characteristics Are defined. Aerodynamic characteristics of current collectors are constructed.

The article presents the results of modeling the force fields in the elements of the wheel-motor unit of the electric locomotive 2ES10. The mathematical model is obtained on the basis of the Lagrange equations of the ΙΙ kind. A design scheme for the study of the dynamic behavior of the wheel-motor unit is presented. Expressions for the deflection of the elastic elements of the traction motor suspension, elastic and dissipative forces are given. A method for determining the vector force field at the articulation site of the bracket and thrust suspension TEM is proposed.

The article deals with the analysis of methods for obtaining statistically reliable data on contact pressure, which are based on the results of inspection trips and data on the design values of the location of the contact wires in the vertical plane andin the path plan. A method for calculating contact pressing with artificial neural networks is proposed. The methods of obtaining statistically reliable data on the contact pressing of current collectors of electric rolling stock without the need for direct measurement, based on the video image of the current collection process and analysis of external factors (weather, operational) accompanying the interaction are considered.

The work is devoted to the consideration of the possibility of using composite materials with an aluminum matrix in the design of electric transport pantographs. Currently, there is a tendency to increase the speeds of electric transport. This fact requires reliable and high-quality current collection, which can be achieved by reducing the mass of the current collector design, including through the use of composite materials. The possibility of using composite materials in parts and assemblies of current collectors operating under conditions of increased current loads and at high speeds of movement and the mechanical characteristics of the traditional ones used in the carriage design and the composite materials proposed for use are analyzed. The design of a carriage of high-speed electric rolling stock has been developed, in which an aluminum matrix composite material was used as a structural material. Statistical modeling using the finite element method in the SOLIDWORKS Simulation software package was performed. Comparison of the strength characteristics of carriage assemblies made of traditional materials and aluminum matrix composite showed the possibility of reducing their weight in the case of composite use without reducing the strength of structural elements. The static characteristic of the carriage in which the composite material was used coincides with the static characteristic of the carriage made of traditional materials, which confirms the possibility of using an aluminum matrix composite without making significant changes to the carriage design. To evaluate the dynamic characteristics of the composite carriage and its effect on the dynamic characteristics of the pantograph, modeling was carried out using the methods of multibody modeling of SOLIDWORKS Motion. The obtained simulation results indicate an improvement in dynamic characteristics when using composite materials, which has a beneficial effect on the reliability and quality of current collection.

The problem of the assessment of the continuous welded rail track stability at its thermal elongation is considered in this paper. The method for determining the stress-strain state of various elastic objects developed by the specialists of JSC “VNIKTI” is analyzed on the example of a rail of a continuous-welded track section. The essence of the method is to determine the dependence of the natural frequencies of rail vibrations on the applied longitudinal force. As a means of obtaining such a dependence, a modal analysis of a track section model carried out using the finite element method was chosen. The methodology for calculating the natural frequencies of rail vibrations and the description of the created model of the track section and its properties are presented in the paper, the contact interactions of the model elements and boundary conditions are defined in it. Calculations for determining the natural frequencies and modes of rail vibrations are performed, the first four modes of rail vibrations obtained by calculation and experimental methods are shown. The assessment of the adequacy of the created model of the track section is carried out by comparing the natural frequencies and modes of rail vibrations obtained by calculation, by modal analysis methods and experimentally when measuring vibrations on a full-scale object - assembled rails and sleepers, having a similar design compared with the model. It was decided to use the distance between the vibration nodes as a criterion for comparing the obtained modes of natural rail vibrations. The first mode of vibration is selected for further studies. Calculations were carried out and the dependence of the natural frequency of the first vibration mode of the rail on the longitudinal force applied to it was obtained using the created model of the track section. The obtained dependence can be used in the method proposed by the specialists of JSC “VNIKTI” in order to determine longitudinal force, applied to the rails on the full-scale section of the continuous welded rail track.

In this article, the problem of assessing the stability of a continuous welded rail track during its thermal elongation is considered. The article considers the method of determining a stress-strain state of continuous welded rails proposed by specialists of JSC “VNIKTI”, which is based on the use of the dependence of natural frequencies of rail vibrations on the applied longitudinal force. Such a dependence can be obtained with the help of the calculation method using a finite element model of a track section. The reliability of such a dependence can be assessed by comparing the results obtained using the calculation method with the actual values of natural frequencies of rail vibrations, depending on the longitudinal tensile and compression force applied to a full-scale facility. The track panel is chosen as such a facility. In order to obtain the actual dependence of natural frequencies of rail vibrations on the applied longitudinal force, a specialized test bench is developed. The development of the test bench included designing the test bench elements and creating finite element models of main load-bearing elements of the test bench - a stop, support and traction, as well as their subsequent strength calculation to confirm the operability of the selected design under necessary loading conditions. The strength is assessed using the safety factor for the yield strength. Calculations using the finite element method have shown that the test bench design has sufficient strength. The developed test bench will allow performing tests for the purpose of the verification obtained using the calculation method of the dependence of rail vibration frequencies on the longitudinal tension and compression force applied to it, as well as for testing the proposed method to assess the rail longitudinal force during its thermal expansion.

The paper considers the influence of the force characteristics of the damping apparatus on the value of the maximal longitudinal forces arising between the cars. Using the computer program MSC.ADAMS, we performed the simulation of shunting collisions of cars and train transient movement modes. The dependences of the maximal forces at cars' collision at various velocities on the shape of the elastic elements' force characteristics are determined. The operation of various shock dampers for the case of the train starting off electric braking and movement through the parts of the longitudinal track profile was estimated. It is shown that shock dampers with a rapidly growing line of load lead to the emergence and propagation of large shock forces along the train, while a slow growth of the force leads to their reduction due to the amplitude increase in elastic vibrations propagated along the train length . We propose to use high-energy-damping devices to reduce the longitudinal forces in the train, which are characterized by the force slew rate substantially depending on the compression velocity of the shock damper.

In this article, the process of wear of the material of the ridge of the wheel brace during the movement of the locomotive in a curve of a given radius is considered. The methodology of the study considered in this article was that, based on the expression for the depth of penetration of the rail head into the material of the bandage ridge, the movement of the wheel along the inner rail in the curve was considered. It was taken into account that the contact point on the ridge of the bandage will move along the edge of the rail with slippage and that the contact area is a fairly narrow surface with a border close to an ellipse. Formulas for calculating the speed and the slip path of the contact point of the ridge of the locomotive wheel brace with the rail are obtained. As a result of the study, equations were derived to estimate such quantities as the volume, intensity and wear rate of the bandage (per revolution of the wheel). It is shown that the expressions obtained as a result of the work carried out can be used to calculate the intensity of wear of the brace ridge when the locomotive is moving in a curve of a given radius. The amount of the ridges material wear of the wheelset bandages can be determined on the basis of the equations obtained individually for a specific locomotive series and a given range of its operation.

Issues related to the wear of the rail and wheel tread of a locomotive are always of great interest to both operational services and scientists. Knowledge of the influence of technical and operational factors on the intensity of wear of the materials of the contacting bodies would save material and financial resources. The proposed article is devoted to determining one of these parameters, namely, the depth of indentation of the material of the rail head into the material of the wheel rim flange. The force interaction of the bandage crest and the rail head occurs mainly at the level of irregularities in the contact area. The wear of the material of the contacting bodies will be determined by the depth of penetration of irregularities in the contact area and the speed of relative slip. An important parameter for assessing the magnitude and nature of wear is the relative penetration depth of the contacting bodies. In this case, the magnitude of the collapse of one of the contacting bodies is equal to the depth of penetration of another body into it. Calculations of the main radii of curvature of the surfaces of the rail head and bandage crest at the point of their contact are made, and the dimensions of the contact area are determined. As a result, expressions were obtained for calculating the depth of mutual penetration of the materials of the shroud crest and the rail head. The rail head material has a deeper penetration into the shroud tongue material. The force contact between the bandage crest and the rail occurs mainly within the limits of plastic deformation of their materials. Formulas are obtained for determining the magnitude of the approach of the contacting bodies and the highest normal stress in the contact zone. An estimate of the values of the collapse of the material of the rail head and the bandage crest was made, which makes it possible to judge the percentage of their wear. With force contact, the wear of the wheel rim flange is much higher than the wear of the rail head.

At present, the “Afrosiyob” high-speed passenger train runs on the Tashkent - Samarkand, Samarkand - Karshi, Samarkand - Bukhara sections. In the near future, it is planned to launch freight trains on sections of the Bukhara-Misken route. On high-speed double - track sections Tashkent - Samarkand, Samarkand-Navаi, the movement of freight trains is combined with passenger trains. Which, in turn, negatively affects the throughput of stations and hauls. In connection with this, the actual issue is the movement of freight trains on these sections. Additional research is needed to increase the capacity of sections where freight and high-speed passenger trains run. The article considers options for the aerodynamic interaction of freight and high - speed passenger trains moving in one or the opposite direction. At the same time, the idea of the safe organization of freight trains during the movement of high-speed passenger trains was put forward. As a result of this study, the possibilities of carrying cargo trains in one direction or in the opposite direction are determined by ensuring the safety of movement on two-way parcels in which high-speed “Afrosiyob” high - speed electric trains travel. This makes it possible to develop recommendations for more effective use of the ability of parcels to conduct trains. When calculating the aerodynamic interaction, scientific ideas put forward by scientists from Europe, the USA, Russia and other countries were analyzed. Methods for solving the Navier - Stokes equations using existing programming models are described.

The article discusses the traction parameters of a new generation electric locomotive. The existing schemes of service areas by electric locomotives and locomotive brigades on the studied railway test site are presented. A comparison is made of the main parameters of DC and single-phase AC electric locomotives, the operation of which is currently organized on sections of movement with trains of calculated mass in the long-term mode of thrust on the climbs of various steepness. The scheme of the proposed organization of operation of a double power locomotive and locomotive crews is presented. Calculated traction parameters of a two-system electric locomotive, taking into account the plan and profile of the track in the proposed areas of operation, specific resistivity to the movement of the locomotive and the composition of the train at the estimated speed, specific accelerating and decelerating forces of the train. When two-system electric locomotives are put into operation, it will be possible to reduce the fleet of locomotives in operation, the number of traction arms due to their lengthening and the number of locomotive change points, reduce the transit time of freight trains, increase technical and local speed, average daily mileage and average daily performance of the locomotive, reduce power consumption per traction . The operation of such electric locomotives contributes to the development of polygon technologies for managing the transportation process, improving the quantitative and qualitative indicators of various railway enterprises.

In article methods of valuation electrical parameters and mathematical models of electic processes of reinforced concrete construction are considered. The conclusion that influence of reinforced mesh was not taken into account in describe models had been done. Method for prediction of reinforced concrete foundation which based on equation system of electric field in conductors and finite element method and allowed explicit geometry of object include reinforced mesh was suggested by authors. Authors done the assumption about invariability of potential of reinforced mesh which covered of concrete layer for direct current and alternating current due to ratio of steel and concrete resistance. Realization of nethod was done by dint of software complex Comsol Multiphysics. Research object was reinforced steel foundation TSS-4, which is located in ground. Result of research was represented color epure of potential distribution and line of current density. Reinforced concrete construction current and current which flow into armature were determined by dint of integration of normal current density on surface where set the external potential and surface of armature. On the grounds of determine values of model current resistance of model depending on resistivity of concrete and ground were calculated.

This article presents promising and widely used in transport construction methods of earth bed reinforcement with the use of geotextile as a reinforcing and separating layer. It was suggested to lay down geotextile coverings manually in the zones of rail joints of an equalizing span of a continuous-flow track by 6-10 sleepers in each side of the joint, in all, 12-20 sleepers where high-speed and high-speed passenger traffic is expected. Basic technical requirements and restrictions on geometric dimensions for geotextile when reinforcing the main track bed are given. The technology of manual laying of reinforcing geotextiles when a small section of the railway track needs reinforcement during routine maintenance and repair of the railway track is given. The sequence of basic manual laying of geotextile coverings in the technological "windows" is described. Experimentally conducted work on the device coatings of geotextile manually in the areas of rail joints equalizing span of permanent way for 6 sleepers on each side of the junction in the railway sections of the Tashkent railway station (PCH-2). A design for reinforcement of the main ground in the areas of rail joints has been proposed. The basic requirements to quality control of construction works in structures with the use of a layer of geotextile materials are given.

The article discusses the design features of the mechanical and crew parts of the passenger electric locomotive DC EP2K, which directly have or causes an impact on the rail track. The purpose of the work is to consider the features of the interaction of the crew and the track when moving this electric locomotive in small radius curves by evaluating the forces arising in the "wheel-rail" contact of the three-axle bogies of the EP2K electric locomotive under these conditions. The need to solve such a problem is caused by the results of the analysis of statistical data on the wear of the ridges of the wheels of EP2K electric locomotives. These electric locomotives are operated at the united railway landfill, where there are a large number of curved sections, including curves of small radius. To achieve this goal, a design scheme of a three-axle trolley of an EP2K electric locomotive has been compiled, which allows a quantitative assessment of the forces acting in contact with the wheel ridges with the relay heads. According to the calculation scheme, a system of equations has been compiled, the solution of which makes it possible to estimate the forces between the ridge and the inner face of the rail head. Based on the results of the calculation of the guiding forces of the wheel pairs of the three-axle bogie of the EP2K electric locomotive, it is concluded that the values of the guiding force acting on the second wheel pair are comparable to the forces acting on the first and third wheel pairs, and in some variants even exceed the values of these forces. The obtained results can be used for further research on the development of measures aimed at reducing the wear of the ridges of the wheels of electric locomotives of the EP2K series under operating conditions.

The reinforcement of a soil subgrade by solidifying grouts injection, outside the limiting dimensions of train movement, can significantly increase the cost efficiency and manufacturability of strengthening. The paper suggests the most appropriate methods to strengthen the subgrade depending on the stage of defects and deformations development.

The results of edge stresses and stress measurements in the neck of the rail in a curve of radius 380 m, obtained in the tests on the effects on the way the locomotive CKD6e-2108, freight gondola 12-9941 and 12-9920, on railway line Almaty - Chu. The dependences of the stresses in the edges of the soles and neck rail on the speed of the test vehicles. The possibility of a transition from stress to lateral forces.