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The article considers an important scientific and technical problem of determining the transient resistance in the “rail - ground” system, which is of critical importance for ensuring the safety and efficiency of railway transport. The subject of the study is the mechanism of electric current spreading through the ballast layer, taking into account the features of the contact interaction between the rail and the crushed stone. The purpose of the study is to develop a comprehensive methodology for calculating the electrical parameters of a railway track. To achieve this goal, an analytical modeling methodology is applied that takes into account the mechanical characteristics of the system, the resistivity of materials and the influence of the water layer. In the course of the work, a mathematical model was developed that allows taking into account various configurations of crushed stone contact with the rail, including lateral contact and clamping under the rail. Special attention in the study is paid to the analysis of the influence of mechanical stress in the contact zone, surface and volume conductivity, as well as the effects of contamination and moistening of the ballast layer. As a result of the research, methods for calculating transient resistance have been developed, taking into account various factors, and graphs of resistance dependence on key system parameters have been constructed. The practical significance of the work lies in the possibility of applying the results obtained to predict the electrical characteristics of railway tracks, optimize their operation and increase electrical safety. The developed technique makes it possible to take into account the key factors affecting the transient resistance: the condition of the crushed stone surface, volume and surface conductivity, and mechanical stress in the contact zone. This makes it possible to more accurately assess the electrical characteristics of a railway track and make informed decisions on its maintenance and repair. The study showed that surface conductivity (due to contamination and water film) often has a more significant effect on the overall resistance of the system than the bulk conductivity of the material.

A variant of application of a contact compensated chain suspension with levers and lateral current collection for a three-phase traction power supply system (TSTE) is considered. Two different-phase contact suspensions are located on different sides of the track axis. The electric rolling stock must have two current collectors that press on the contact wire from the track axis in opposite directions. The description of the design of the contact suspension as a whole and the main components, in particular, the fastening of the rods, which makes it possible to provide a vertical zigzag and limit the transverse movement of the contact wire, is made. At points at the supports, the levers are connected to the consoles and have a knot to create angular rigidity. In addition, the rotation of these levers is limited towards the axis of the path and in the opposite direction. This prevents the possibility of lashing of different-phase contact wires. In accordance with this design, a mathematical model of this contact suspension was developed based on the finite element method, which provides calculation in statics and dynamics, taking into account the current collector. To describe the pantograph, a common three-mass model is used. Based on the analysis of the results obtained using this model, the influence of the design parameters of the suspension, cross wind and the speed of the pantograph movement on the quality of the current collection is determined, the limits of applicability of the suspension under consideration, depending on the value of these parameters, are established. It has been determined that, in contrast to a conventional contact suspension with a vertical current collection, for suspensions with a lateral current collection, a side wind has a significant effect on the quality of the current collection. It is the wind speed that is the main factor limiting the possibility of using a suspension with lateral current collection.

In the article the finite element model of the electrical contact pin wire - collector strip, which takes into account the complex interaction of electric and thermal processes. As the contact wire is selected worn MF-100, the current collection plate - two brands VJZ-metal and graphite. Microgeometry the body surface at the contact point is obtained based on the model of Greenwood - Williamson. It was considered the two extreme cases of possible contact between the contact wire to the plate. The results were analyzed and compared with the known experimental data. Calculated at what proportions contact force and contact current due to burnout occurs spark or arc. Identify ways to improve the model.

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.