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He method of researching the dynamic properties of the railway crew in the action on it harmonic parametric perturbation, caused by the changing rigidity of the base of the rail, is set out. For such differential equations there are no regular methods of solving them, moreover, their exact solutions are not known at present, so they are used by approaching methods. A two-degree mechanical system with a harmonic parametric perturbation described by a system of ordinary homogeneous differential equations is considered. One of the hard-bone parameters is a function of time and varies from 2000 to 3000 N/m. To calculate the boundaries of dynamic instability (parametric resonance) a method of generalized Hill definers is used, which does not require the introduction of small parameters. The area of interaction of parametrically excited and forced vibrations has been determined.

The article considers the dynamic processes of the oscillatory system «wagon - way», its mathematical model is formed and its features are established. The analysis of existing approaches to the consideration of the influence of dissipative forces on the stability of rolling stock is carried out, their shortcomings are revealed. When composing dynamic process equations, it is important to proceed from their exact expressions when considering kinetic and potential energy, i.e. to take into account the relationship between generalized coordinates, which will allow us to consider in detail the process of rolling stock oscillations. The zone of autoparametric resonance is found. It is established that dry friction forces do not interfere with parametric resonance. Dynamic equations are compiled taking into account the scattering forces arising in the contact points of the structural elements of the car. The influence of dry friction forces on the critical coefficient of parametric excitation is determined. The areas of dynamic instability of a car when moving along a railway track with different characteristics are determined. The features of the behavior of the system under the influence of dry friction forces are revealed. It is established that dry friction forces do not reduce the amplitude of bouncing and can lead to an increase in lateral pitching vibrations due to energy pumping.

It is shown that dynamic systems, «rolling stock - way» due to the unevenness of the path on length should be described by ordinary differential equations with variable coefficients, the method of analyzing differential equations with constant, variable and random coefficients describing the movement of electric locomotive nodes when they move along an uneven path. In the transition to a new paradigm, we can talk about areas of dynamic instability, which in the case of simple parametric resonances develop near critical frequencies, but this is not one specific point, but a zone that expands with increasing coefficients of parametric excitation. In addition, the presence of friction in the system does not guarantee the limitation of resonant amplitudes. The effect of parametric arousal factors on the width of the dynamic instability zone has been established. There are many other features in the behavior of differential equations with variable coefficients, so it is impossible to replace the action of unevenness with some equivalent geometric irregularity, since at this moment there is no exact solution to the problem with which to compare the results of approximate mathematical models.

Based on the analysis of the empty rolling stock on the Krasnoyarsk and East Siberian Railways, the technical parameters that have a significant impact on the unloading of the wheel of the first wheel pair in the course of movement are determined. The design features of wagons influencing the safety coefficient of train traffic are considered. Statistical processing of these gatherings, according to the materials of official investigations, revealed a number of interesting features. One of them is non-normalized total gaps in the sliders along the diagonals of the wagons. This fact in the movement of empty car causes misalignment of the body, which in turn leads to a redistribution of the loads acting on the spring kits on the sides of carts and wagons. The influence of elastic suspension parameters (height, spring break) on the redistribution of loads acting on the sides of the trolley is considered. The misalignment of the body of empty wagons, especially wagons with a sufficiently small mass of unsprung parts and a high center of gravity, leads to a significant reduction in the safety factor. The calculation of the transverse guiding forces acting at the point of contact of the wheel and rail, as well as their effect on the unloading of the wheel. It is revealed that the body skew leads to a significant increase in lateral force, which affects the stability of the empty rolling stock.

The article suggests that the reason for the increased wear of the tires of electric locomotives with an asynchronous traction drive is the increased sliding speed in the contact of the wheels with the rails. It is shown that in thrust modes with high sliding speeds, frictional self-oscillations can develop in the drive. The stability zones of the drive are constructed in the space of its parameters. The model of an asynchronous drive with a «jammed rotor» for the study of skidding modes has been substantiated. It is recommended to install a clutch control system (СCS) on the electric locomotive to reduce wear on wheels and rails. СCS intelligent sensors create an additional feedback channel for the system of optimal traction control - the implementation of maximum traction forces with minimal friction losses. The methods and recommendations presented in the article are applicable to various designs of traction drives.

The mathematical model of traction drive Electric locomotive EP20 for research of dynamic processes in a mode of boxing is constructed. The natural frequencies and coefficients of the forms of the dynamic system are determined. The stability of the drive in relation to frictional self-oscillations is estimated. Dynamic loads in the drive elements at a single angular speed of wheel slip are calculated. The recommendations on increasing the dynamic qualities of the traction drive in the sliding mode are formulated.

This article is devote to the development of software for analyzing and transforming data from studies of the collector surface traction motors using a device of control profile commutator PKP-4M. The use of this computer application during the processing of the experimental data will improve the reliability of the control profile of the commutator, and to calculate the main diagnostic parameters characterizing the effect of the profile on the commutation process.

Explores the impact of truly existing longitudinal non-elastic railway track caused by the presence of sleepers and other factors on the vertical dynamic of vehicle. Formulas to determine the bounds of simple combinational and parametric resonances is obtained. Areas of dynamic instability of electric locomotive EP2K is builted.

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.

Example of the methods to evaluate conditions and reserve of transverse stability in CWR curves under abnormal track maintenance is discussed in the article. The author presents the results of the research of this method and also its positive effect is described.

Vibration levels in the subgrade for the movement of trains are investigated. analysis of the recorded accelerograms is made, acceleration fluctuations on the cross section of the embankment are installed. Calculations of the stability of embankments with the effects by the train load are produced.

The use of three-dimensional reinforcing structures is an effective method strengthen the slopes and the primary site of subgrade, it is confirmed by a complex of experimental studies. The numerical and natural modeling processes associated with the strengthening of subgrade geokompozitn structure. Natural modeling performed by the embankment of equivalent materials using real ground conditions and loadings identical in size natural. A comparison of simulation results showed high convergence, which allows use it’s in the preparation of design techniques.

The object of the research is the solid rocks massif containing the Kuznetsovskiy tunnel with a length of 3890 m, the greatest depth of the deposit is 355 m, which crosses the mountain pass section of Sikhote-Alin on the Komsomolsk-Sovetskaya Gavan line of the Far Eastern Railway. The aim of the studies was a detailed analysis of the engineering and geological conditions of the facility and their impact on construction and operation. These data are obtained as a result of field research, laboratory testing of physical and mechanical properties of rocks, evaluation of water flow to drainage structures and analytical calculations. The massif is composed by terrigenous rocks - a rhythmic interlayering of heterogeneous grained sandstones, siltstones, gravelites, conglomerates, that are classified as strong. Layering has a steep drop and a sublatitudinal strike, deviating from the axis of the tunnel by 20 - 60 °. The tunnel axis is crossed by a system of faults of various capacities, their total capacity is 334 m, which is 8.5% of the length of the tunnel. The fault zones are associated with increased fracturing, reduced stability, in places abundant water inflows that have peaks in the summer, the threat of landslides, intense silicification and sulfide mineralization. The obtained monitoring materials by methods of recording natural pulses of the electromagnetic field of the earth (NPEFE) (EEMEMP) and dipole electromagnetic profiling (DEMP) allowed to draw a conclusion about the real picture of the development and forecast of the rock pressure, as well as the dynamics of the groundwater entering the mine for safe construction and operation. The state of the geodynamic conditions of the mountain massif is characterized as stable. Available data can be used as a starting point for assessing and forecasting aspects of the construction and operation of the second stage of the tunnel.