The authors developed a model for predicting and assessing the efficiency of railway transport from the border of one state to the border of the other one, taking into account all expenditures by the net present value indicator net present value of discounted cash flow. The results allows planning measures to accelerate the cargo delivery, both on the territory of Ukraine, and during the transfer of cargoes at border stations, to predict the revenue generation from the implementation of international transportation, which is very important for attracting investments.
Purpose. The main purpose of this paper is to analyze the existing methods for surveying curves in a plan, to study the influence of the errors in measuring plan parameters on the permitted speeds of motion, to develop re-commendations for reducing road disturbances by bringing the parameters of curves to the standards that operate in Ukraine in the directions of accelerated and high-speed train traffic. The problem of restructuring the curves was not so acute until there was a need to increase the speed of motion and technical condition monitoring of the track plan. Unreliable determination of the curves parameters leads to unjustified restrictions in the speed of motion or to large volumes of straightening operations. Methodology. The methodology used in the paper provides for a comprehensive and detailed study of different ways of railway curves survey, aimed at developing and obtaining the optimal solutions for the railway track plan. To date, there are different methods of survey the actual geometry of the railway track. To carry out research in various sections of complexity and for a long time of the railway track operation, the most convenient, first of all, considering the regularity of arrivals, there is a tape of the track-measuring car. However, this method is used to assess the state of the railway track, and not to determine the exact geometric position. Thus, when trying to determine the actual outline of the track unevenness using a track-measuring tape, a number of difficulties arise. When forming a mathematical model of the existing plan, the assumption is used: it is considered that three adjacent points on the curve are located along the circumference. The work of track renewal trains is based on this principle. As a result of track renewal operations with the aim of reducing the volume of flattening, the curve does not correspond to the initial passport data. Findings. The results of the work come out of the analysis of different approaches and methods of surveying the plan of the line, the parameters influence of the curves on establishing the permissible speed of motion. The recommendations received in the work will help to increase the efficiency of design decisions and the quality of railway track reconstruction as a whole. Originality. Scientific approaches to assessing the state of curves, studying the influence of their parameters on the permissible speed of trains, have been further developed. The system of criteria for assessing the state of curves that affect the accumulation of track disturbances in the plan is supplemented. Practical value. The results obtained will be useful for carrying out measures to improve speed, improve the smoothness of train traffic and the level of travel comfort on curved track sections, especially in the areas of accelerated and high-speed train traffic.
The authors developed a model based on the dynamical theory of elasticity, which allows us to describe the dynamic equilibrium of strains of the railway track layers. The model of the stress-strain state for the railway track consists in a combination of the geometry equations of the outline of a part in the system’s space, involved into interaction at a given time and the equations of the dynamic equilibrium of its deformation. Considering the obligation to register the course of the process in time, for each time step of integration the outline of the strains propagations front is determined. The strains propagations front is described by the equations of propagation in the material of the elastic spatial wave of oscillations. It allows determining complete spatial-temporal account of the deflection dynamics of the rail support, which enables the execution of calculations, including for conditions of fast-speed and high-speed trains. With the application of the developed model, a number of scientific and practical problems were solved.
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