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To increase the level of mechanization and automation of the assembly processes of rail and sleepers, link assembly lines are installed at the production bases of the track machine stations. In 2012, a semi-automatic link assembly line of KB03 brand was introduced on the Belarusian Railways for the assembly of a rail-and-sleep grid on reinforced concrete sleepers with an SB-3 intermediate fastening. Increasing the productivity of this line is a priority area in research, since in modern conditions there is an increase in the volume of overdue railway track repairs. In the course of the study, it was determined that the most rational solution for studying the work of a link assembly line and finding ways to increase the productivity of its work is to use simulation tools. After studying the technical and other accompanying documentation, a simulation model of the KB03 assembly line was developed. Then the developed model was validated, during which it was found trustworthy and suitable for experiments. Based on the analysis of the results of the experiments carried out on the model, solutions were formed to control the production process of the KB03 assembly line to obtain the maximum increase in its productivity. The calculation of the economic feasibility of introducing the proposed changes and adjustments to the technological process of the link assembly line in production was carried out.

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.

This article discusses the problem of loss of elastic properties of Pandrol Fastclip rail fasteners during operation. The research is related to predicting the dynamics of changes in the elastic properties of the Pandrol Fastclip clamping terminals during their long-term operation and provides for the creation of control methods (regulation) by pressing the fastening terminals on the sole of the rails, which guarantees the safety of trains with set speeds. On the basis of the conducted research, the design of a device that increases the pressing force of the fastening terminals on the sole of the rails has been developed. This device will provide optimal parameters for attaching rails to the sub-rail base at all stages of railway track operation. At the same time, there will be no need to replace the expensive imported elastic terminals of the Pandrol Fastclip fastening in cases of a decrease in the elasticity of the terminals in the current path. The research results are relevant for dozens of foreign railways where modifications of the Pandrol Fastclip fastener are operated: Pandrol Fastclip FC, Pandrol Fastclip FCA, Pandrol Fastclip FE, Pandrol 350, Pandrol SFC, Pandrol 1520, etc. The proposed technology for carrying out work to improve the technical condition of the intermediate rail fastening structure will not require the provision of "windows" in train schedules, which will not affect the carrying capacity and capacity of the railway track and will not affect the delays of scheduled trains.

Based on the proposal for the formation of a railway track for operational deployment without ballast using a sub-rail base with a viscoelastic element forcedly filled with Newton's fluid and laid on an unprepared surface without ballast, an example of calculating the interaction of a wheel and a rail with this element based on the energy method is given. The possibility of using the design of the under-rail device for the operational laying of a railway track in difficult conditions on an unprepared surface without a track ballast layer is substantiated. The elastic dynamic impact of a wheel on a rail with initial speeds along a sub-rail base in the form of a box with shells laid on an unprepared surface is considered. The kinetic energy of a wheel hitting a rail laid on the proposed under-rail base passes not only into the potential energy of deformation, but also into the energy of wave and oscillatory processes. To improve the accuracy of solving the problem of dynamic impact, the transition of a part of the energy into the energy of local deformations in the contact area of the wheel with the rail is taken into account. Within a short period of time after touching the wheel at a certain speed, all elements of the rail acquire a certain strain rate. It is assumed that at the moment of contact with the wheel, the rail does not change its original shape, and the decrease in the speed of the wheel occurs due to local deformation of the materials of the contacting bodies; this period of impact will last until the velocities of the two bodies are equalized, after which the shape of the middle surface of the rail, modeled by a Bernoulli-Euler beam, will begin to change. Since the kinetic energy of the wheel is converted into the potential energy of bending, it is taken into account in the calculation to take into account the mass of the impacted body as the load of the wheel on the rail.

Special attention on the Belarusian Railway is paid to the issues of operation of curved-linear sections of the track, since in the framework of solving the problem of increasing train speeds; one of the significant obstacles to changing the speed regime is the discrepancy between the actual position of the curve of the project documentation. The automated systems of mobile diagnostic tools used on the road fully allow us to evaluate the actual parameters of the curves, which can form the basis for modeling the desired positions of the curves for the purpose of their certification. For this purpose, various orders and orders are drawn up annually, which set the main parameters of the curves in the plan and level, as well as the volume of work on the reconstruction (modernization) of the curves in order to bring them to the project documentation. In the Methodology introduced at the Belarusian Railways for evaluating the actual parameters of the installation of curves of track sections, general provisions given for the regulations that determine the procedure for performing actions when performing qualitative and quantitative assessments of the parameters of the geometry of the rail track. Depending on the state of the actual parameters, it is assumed that the curve will be assigned a certain status, which determines the order of its further operation, and depending on the ratio of the actual parameters relative to the design parameters, the degree of violation. The parametric analysis of this technique allowed us to generalize the results of structural, functional and informational analyses of the order of assessment of the level of disorder of curves, with assigning them the appropriate status, and the value of indicators that determine the degree of violation. The study of the parameters of curved sections revealed discrepancies in the qualitative and quantitative estimates of the same track sections, as well as the need for a comprehensive assessment of the actual and design parameters of the rail gauge geometry.

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 is devoted to the problem of elimination of thermomechanical damage on the surface of rolling wheel pairs of cars, which arising from the use of brake shoes to reduce their speed. A new design of the brake shoe equipped with electromagnets, which provides braking without jamming the wheel pair. Article contains calculation of the braking force and the provide slowdown .

The development of railway transport is currently impossible to imagine without the use of mathematical models and algorithms. Consider the increase in speeds, reduction of travel time, while minimizing costs, is possible only with the qualitative and full use of the mathematical apparatus. The use of information technologies makes it possible to take an effective decision in the development of a project for the reconstruction of a railway line. The current state of the theory of railway transport is characterized by the presence of a developed system of mathematical models and algorithms for analyzing various features of railways. This opens up possibilities for building an approach to the problems of searching and optimizing design solutions on a mathematical basis, with the reduction to a minimum of costly and time-consuming physical modeling procedures. One of the main tasks that are set for the railway transport in the near future is to increase the speed of trains on existing railway lines with the use of computer technology (computer-aided design). The article deals with the problems of technical reconstruction of the railway plan to increase the speed of train movement. The urgency of the use of computer mathematical methods for the development of an optimal plan for increasing the speed of trains. A pair of mutually dual problems of optimal reconstruction of railway curves to increase the speed of trains with minimal capital investment is considered. As methods for solving the problems posed, the following methods were proposed: the method of steepest descent, a modified method of dynamic programming (the Cattell method), the method of indefinite Lagrange multipliers. The expediency of using each method to solve the problem is indicated. The considered methods allow to implement a number of computer-aided design procedures for the reconstruction of the railway plan.

Examined the effect of oil pollution on the ballast bed of the railway track, namely, the effect of oil and oil products on the following functions performed by the ballast bed: maintenance of the rail-sleeper grid, perception of loads from rolling stock, filtration of melt and rainwater. Ballast oil pollution leads to an increase in its distribution in the environment. Oil and oil products have a strong negative impact on the environment, which leads to degradation of vegetation. The causes of oil contamination of the ballast bed, which lead to disruption of its functions, are determined. Attention to increasing the humidity of the ballast in the wintertime, which leads to freezing of the ballast and an increase in the stiffness of the path. Considered a method for cleaning gravel with a gravel-cleaning machine and revealed shortcomings. Studies of the effectiveness of washing oil-contaminated ballast gravel with O-BISM detergent in the absence of mechanical influence on the sample, as well as with the use of barbation and mixing of the sample. The optimal technological mode of application of the washing solution is established. Proposed an option for improving the cleaning of ballast gravel from oil products with a gravel-cleaning machine to solve the problem of efficiently cleaning the ballast gravel from oil pollution, which will solve the problem of crushed stone reuse and utilization.

The article deals with the issue of the interaction of the track and rolling stock and the relationship of factors affecting the comfort of passengers. Examples of passenger comfort indicators are given and possible causes of deviations in the track geometry are considered. The results of experimental trips are analyzed and the data obtained by standard diagnostic tools are presented. Natural irregularities in the plan and profile were constructed in the analyzed areas where comfort indicators were exceeded. The data presented demonstrate the use of an additional indicator of the interaction of the track and rolling stock, which is advisable to take into account to identify deviations in the geometry of the track gauge when carrying out work on the current maintenance of the track, since there are irregularities or combinations of irregularities in the track that have an increased dynamic impact. It is worth noting that currently not all irregularities are registered, and accordingly such irregularities are not eliminated. Using the «passenger comfort» indicator calculated from the accelerations occurring in the elements of the rolling stock, it is possible to determine the places and deviations of the geometry of the track gauge that affect the dynamic characteristics of the rolling stock, causing increased comfort indicators.

In the course of scientific support of design, construction and operation, as well as forecasting the development of transport infrastructure in the Arctic region, RUT (MIIT) scientists have proposed a methodology for working out new design and technological solutions by testing them on a small section of the route that has received the status of experimental; a number of solutions have been proposed that can be taken into account and used during the development of transport infrastructure in the Arctic. To verify the university's developments, a number of expeditions were undertaken to study the features of the conditions of construction of transport facilities, including climatic and engineering-geological, as well as the condition of existing transport facilities (the Salekhard - Igarka Polar Highway): survey expeditions in 2005, 2012; joint expeditions with the Russian Geographical Society with the participation of scientists from the Institute of Roads, Construction and Structures of the Russian Institute of Transport (MIIT) in the Arctic region in 2019 - 2021, during which a geomonitoring network was organized; data on temperatures in the air, near-surface zones and in the ground environment were obtained; the analysis of the ground environment was carried out; recommendations were given on the specifics of the construction of transport facilities, including the construction of the roadbed, using different variants of technical and structural and technological solutions. The purpose of the article is to generalize the experience of the development of the northern territories through the development of transport communications and the testing of new structural and technological solutions for the construction of the roadbed by means of a local section of the highway in the status of a pilot site. The approach presented in this article can be used to form a methodology for solving the problem of creating an effective High-latitude Russian transport system in the Arctic zone of the Russian Federation with forecasting trends in its development.

The article shows the relevance of the problem of noise pollution of the environment by railway transport. The purpose of the research is to assess by calculation and instrumental methods the compliance of the existing noise levels in the residential area near the railway tracks with sanitary standards, to propose a set of noise protection measures and to substantiate their acoustic efficiency. The applied methods for measuring and calculating the equivalent and maximum noise levels of the rolling stock comply with the requirements of regulatory documents. The authors took into account the features of the propagation and shielding of sound waves in the existing residential area, background noise, and the traffic intensity of trains of various categories. The results of measurements, calculations and estimates of the noise generated by the rolling stock in the residential area in Omsk are presented. A significant excess of the maximum permissible equivalent and maximum noise levels in residential areas has been established. Comparison of the calculated and measured noise values, taking into account the standard uncertainty of the calculation methods and the expanded measurement uncertainty, showed quite satisfactory convergence of the results obtained and confirmed a significant excess of the sanitary noise standards. A set of measures is proposed to reduce the noise of railway rolling stock at the source of its occurrence and on the path of its propagation in the existing residential area. The dimensions of the embankments of the two sections of the railway tracks allow the installation of screens of low height up to 38 cm, the geometry of which is designed so that, in terms of reflection of the noise emitted by the rolling stock, they are at least equivalent to a standard noise protection wall 2 m high. For the track section located in the recess, it is proposed to install a noise barrier 6 m high and at least 1 km long. Its acoustic efficiency was calculated.

The article discusses the issues of using the technology of replacing inventory rails with rail lashes of a jointless track. For the production of works on the replacement of rail lashes, excavators on a combined course have been selected as the leading machines, which in recent years have been widely used in the production of works for the current maintenance and repair of the railway track. The paper presents the results of a comparative assessment of the use of rail lash replacement technology using attachments and using a pair of trolleys. In order to select the best technology for the production of works on the replacement of rail lashes, a methodology for assessing the economic efficiency of using a particular technology has been developed. The main indicator in the calculations were the given operating costs, taking into account the cost of the machine per unit of work, the cost of relocating the machine, the delay of trains, the wages of track fitters and the discharge of rail lashes. According to the results of the calculation, it was found that it is economically advantageous to replace rail lashes at the front of work up to 4 km using technology using a pair of trolleys, at the front of work more than 4 km, it is advisable to replace rail lashes using technology using attachments. The maximum economic effect when using technology with the use of attachments is achieved with a work front of 10 km. A comparison of the results of work on two technologies gives grounds to conclude that with a three-hour «window», the volume of work performed on the technology with the use of attachments is 1,7 times higher than the volume of work performed on the technology with the use of a pair of trolleys.