Railway Track Representation in Mathematical Model of Vehicles Movement

Abstract

Purpose. The tasks of modeling the interaction of track and rolling stock are basic ones for most areas of modern scientific research of railway transport. The compilation of the model by the principle of Lagrange d'Alembert has found a very wide application for solving the problems of rolling stock dynamics. Representation of the railway track in the model of vehicle movement can be implemented in several ways, which, among other things, will differ in detail. The purpose of this work is to create a methodology for representing the railway track in mathematical models of interaction with rolling stock and obtaining practical results for different characteristics and design of the track and the level of maximum speed. Methodology. The problem consists of determining such track characteristics as the reduced mass, the stiffness coefficient, and the dissipation coefficient. As a tool for solving this problem we used the model of the stress-strain behavior of the railway track based on the joint use of the elastic wave propagation equations to describe the topography of the part of the system that is involved in the interaction at a given time and the equations of dynamic equilibrium of its deformation. This makes it possible to take into account the dynamics of the deflection of the underrail base, which is especially important for the conditions of passenger traffic, which can be carried out at high speed. Findings. The authors obtained theoretically justified stiffness and dissipation coefficients of the railway track for calculating the dynamics of rolling stock in modern models based on systems of equations in accordance with the Lagrange d'Alembert principle. The established values, in contrast to those given in other sources, have a reasonable dependence on the track design and the speed of movement. Originality. The authors expanded the approaches of railroad track representation in models of rolling stock described by systems of equations by the Lagrange-d'Alembert principle. The paper presents the developed method for determining the characteristics of the railway track for such models is based on the results of variant calculations of the dynamic deflection of the rail from the passage of the wheel. Practical value. The authors obtained the values of the stiffness and dissipation coefficients of the railway track depending on the design and speed of motion for practical use in appropriate models of interaction between track and rolling stock.

Analysis of Existing Passenger Traffic by Mode of Transport and Assessment the Competitiveness High-Speed Traffic in Ukraine

“…The share of local transportation in the total amount of intercity railway traffic is 29.5% in passenger units and 11.6% in pass-km, as shown in Figures 2 and 3. According to the data obtained from the State Statistics Service of Ukraine, passenger traffic can be calculated based on known parameters (Kirpa, 2004;Kurhan, M. & Kurhan, D., 2017).…”

Ways of introduction of the high-speed movement of passenger trains in Ukraine

“…As a result, these compositions are capable of performing the following functions:  to achieve a commercial operation speed of 300-350 km/h and a high average income rate in some regions of 250 to 300 km/h (including the use of existing lines and stations). Such income speed significantly shortens the duration of trips, due to which absolutely competitive in comparison with air travel the duration of trips at distances of up to 1.500 km [9,10].  run at high speed due to rapid turnover (design with two locomotives, which makes it possible to easily change the direction at the stations), despite the limited number of trains.…”

“…Taking into account the presented information, the choice of track width for the Ukrainian high-speed network is more operational, financial and political, rather than a technical issue [5,7,10].…”

FEM Modelling Possibilities of Glued Insulated Rail Joints for CWR Tracks

“… At Railway University of Dnipropetrovsk there is a team which researched mainly the evolved stress-strain state of the whole railway track with very sophisticated methods [32] [33] [34] [35]. In the paper [36] they investigated the railway track representation in mathematical model of vehicles movement. Irregular vehicle movements are a key issue related to arising 'extra' stresses in the elements of railway track, also in IRJs and GIRJs.…”