Purpose. Across the track superstructure (TSS) there are structures where standard approach to the decision on the future of their operation is not entirely correct or acceptable. In particular, it concerns the track sections which are sufficiently quickly change their geometric parameters: the radius of curvature, angle of rotation, and the like. As an example, such portions of TSS may include crossovers where their component is within the so-called connecting part, which at a sufficiently short length, substantially changes curvature. The estimation of the position in terms of a design on the basis of the existing technique (by the difference in the adjacent arrows bending) is virtually impossible. Therefore it is proposed to complement and improve the methodology for assessing the situation of the curve in plan upon difference in the adjacent versine. Methodology. The possible options for measuring horizontal curves in the plan were analyzed. The most adequate method, which does not contradict existing on the criterion of the possibility of using established standards was determined. The ease of measurement and calculation was took into account. Findings. Qualitative and quantitative verification of the proposed and existing methods showed very good agreement of the measurement results. This gives grounds to assert that this methodology can be recommended to the workers of track facilities in the assessment of horizontal irregularities in plan not only curves, but also within the connecting part of switch congresses. Originality. The existing method of valuation of the geometric position of the curves in the plan was improved. It does not create new regulations, and all results are evaluated by existing norms. Practical value. The proposed technique makes it possible, without creating a new regulatory framework, to be attached to existing one, and expanding the boundaries of its application. This method can be used not only for ordinary curves, but for very short sections, the curvature of which changes abruptly to its opposite value.

Purpose. Turnouts play a key role in the railway transportation process. One-sided and many-sided curved turnouts were railed over the last 20 years in difficult conditions (curved sections, yard necks). They have a number of geometric features, unlike the conventional one-sided turnouts. Today the normative documents prohibit laying such turnouts in curved track sections and only partially regulate the assessment procedure of their real condition. The question of establishment the permissible train speed within the curved turnouts is still open. In this regard, authors propose to set the train speed according to the driving comfort criterion using the results of field measurements of ordinates from the baseline for the particular curved turnout. Methodology. The article considers the criteria using which one can set the permissible speed on the turnouts. It defines the complexity of their application, advantages and disadvantages. Findings. The work analyzes the speed distribution along the length of the real curved turnout for the forward and lateral directions. It establishes the change rate values of unbalanced accelerations for the existing norms of the curved track sections maintenance according to the difference in the adjacent bend versine at speeds up to 160 km/h. Originality. A method for establishing the trains' speed limit within the curved turnouts was developed. It takes into account the actual geometric position in the plan of forward and lateral turnout directions. This approach makes it possible to establish a barrier places in plan on the turnouts limiting the train speed. Practical value. The proposed method makes it possible to objectively assess and set the trains' permissible speed on the basis of the ordinate measurement of the forward and lateral directions of the curved turnouts from the baseline using the driving comfort criteria. The method was tested using real turnouts, which are located within the Pridneprovsk Railway.

Purpose. The research is aimed at determining changes in the state of the geometrical parameters of the railway track, depending on the passing tonnage in dynamic interaction with the 25 tf/axle load rolling stock. Methodology. For data acquisition, the authors carried out a statistical analysis of the indicators of digital measurements of the track condition by KVL-P track-measuring cars. Using the program of calculating the mean-square deviation of the geometric parameters of the track, the deviation of the track parameters within the test sections was estimated. Findings. During the observation period it was found that on average the intensity of track strain accumulation increases. However, according to the results of the factor dispersion analysis with 0.95 probability, it is impossible to unequivocally state the impact of the factor of using the cars with an axial load of up to 25 tf/axle on the deterioration of the track condition parameters. Herewith it should be noted that the share of cargo carried in the cars with axial load of up to 25 tf/axle during the observation period was less than one per cent. According to the values of the mean-square deviation, the state of the geometrical parameters of the track and their predicted changes were estimated, which showed that the increased axial load will lead to decreased life of the rails, which are the most expensive elements of the track structure, shortened service life of the railroad switches and increased labor costs for workers involved in track repair and maintenance. The corresponding reduction of inter-repair periods, which corresponds to the standards, is projected. In order for heavy-duty wagons not to destroy the infrastructure, there must be at least two limitations: by the types of goods transported and by the speed of movement. Originality. The authors conducted a study to assess the impact of cars with 25 tf/axle load on the state of the geometric parameters of the railway track and proposed solutions to the issue of introducing the 25 tf/axle load rolling stock in Ukraine. Practical value. On the basis of the obtained results it is possible to estimate the impact of the axial load on the intensity of the track condition changes and to predict the reduction of inter-repair periods in connection with the track deterioration and in accordance with the train speed restriction.

The article reveals the quantitative changes in the intensity of failure accumulations in areas with gradual introduction of high axial loads. To obtain the actual values, the authors received three-dimensional array of intensity of rail failure flow. According to the results of the research, it was discovered that the main cause of failure of the rails are the defects in the main contact-fatigue origin. The main factor that impacts the intensity of the rail failure flow is the number of transmitted tonnage. The size of the axial load and curvature of the line pours weight on this process. The proposed rail failure model is a model that can be used to optimize the track maintenance system. The authors conducted a study on the identification of quantitative changes in the intensity of accumulation of track failures in areas with high axial loads and evaluated their influence on the planning of repair and road works. On the basis of the obtained results it is possible to estimate the effect of the axial load on the intensity of changes in the state of the flow rail failure flows.

Object of research: technology of track maintenance optimization Solved problem: In the development of decisions to optimize the decision-making system in the content of the upper structure of the track used methods of control theory, systems analysis, methodology of optimal control. Main scientific results: An analysis of the degrees of research on improving the efficiency of the technical management of railways showed that there was no systematic approach and that existing developments in the organization, in particular the relative optimization, Separate track repair standards or take into account parameter models, process requirements and conditions. Area of practical use of research results: industrial enterprises, railway stations. Providing the stable support of the railway, sustainable and rhythmic operation of railway traffic is ensured. About 7.3 thousand km are exploited in the ferrous metallurgy of Ukraine. More than 70 % of routes are up to 500 km long and belong to a large company. Consequently, an important task is to maintain the technical state of railways at the production demands level. Innovative technological product: combined transportations that can interact with similar networks of foreign countries. Scope of application of innovative technological product: formation and effective functioning of railway-transport complex, improvement of tariff policy, substantiation of perspective parameters of transportation process and its technical means, creation of advanced technologies, choice of rational structure of transport network, formation of transport corridors, development of fundamentally new management systems.