Optimization of life-cycle cost of structures of railway track for different lines is a multi-task. Railway track can be seen as a dynamic system, which is got as the input deteriorating impact - operational load and enhancing impact - maintenance and repair activities. Results of these two effects on physical level are the force indicators of interaction between track and rolling stock and parameters depend on them, which include: forces of interaction in contact point of wheel - rail system; deformations and stresses of elements of track superstructure and in the main level of subgrade; track wear, accumulation of residual deformations in track and its elements. It is known that the actual axial loads on carriage, geometry of the track, irregularities on rolling surface of the wheels and other parameters are random. To analyze the interaction between track and rolling stock in the conditions of the random nature of disturbances methods of the probability theory and the theory of random functions should apply as the input of the system. This article presents the structure and the basic expression patterns of interaction model between track and rolling stock, developed on the basis of methods of the theory of random functions and probability theory. A comparison of results of calculations of interaction between track and rolling stock was made on the basis of stochastic model by calculations of “Universal Mechanism” model and NUCARS. Stochastic methods, the main provisions of which are outlined in this article, make it possible to determine the probability characteristics of the stress-deformation state of the elements of track superstructure and the stresses on the main level of the subgrade with the real flow of operational loads on a given area. This method also helps solving the most important technical and economic problems related to the operation of track infrastructure.

The main difficulty of developing measures for complex evaluation of loading and increasing of resource of running gear parts performance is considering of differences of performance conditions of wheel-rail system. The article presents review of Russian and foreign experience on selection of shapes of carriage wheel profiles depending on the development of railway machinery and changes in terms of operation. It is noted that complexity of task of selecting profile shape is that it needs to consider performance of three different designs: wheel pair, rail and turnout. Each of these mutually affecting designs during its life cycle has its own features in maintenance, terms and forms of wear. The great contribution in development and implementation of the Strategy of improvement of wheel-rail interaction, due to implementation of lubrication technology of the area of contact of wheel flange and side edge of rail head, was made theoretical and experimental studies of scientists and researchers of VNIIZhT. Performing complex measures allows from the middle of 90-ies of XX-th century stabilizing operational work and decreasing operational costs for domestic railways. A conclusion was made on the fact that in modern terms development of interconnecting profiles should be made for express and high-speed lines, specializing for freight and heavy haul service, and operating in mixed service. It is feasible to put common height of wheel flanges of locomotives and wagons, excluding transmission of traction force from locomotives through wheel flange to side edge of rail head, and also to organize profile processing of rails in curves and on tangent sections with rail grinding vehicles to make required form of rail head.

From the middle of the last century, beginning with the works of Professor M. F. Verigo, rejection of yield strength at static loading and transition to the fatigue strength under cyclic loading were accepted and made as the main conceptual provisions in calculations of rails for strength when choosing allowable stress levels. Thus, calculation of rails for the strength should be carried out as all strength calculations of machine parts under loadings, variable in time. Further progress in the development of methods for calculating the strength of rails under varying stresses correspond with the implementation in practice of calculations of probability concepts. In article three types of calculations of rails for strength, having the greatest practical value now, are considered namely: calculation of cyclic strength of rails at prevention of formation of fatigue cracks in a foot and a neck; calculation of cyclic contact strength at prevention within a resource (or probability regulations) of formations of cracks of contact fatigue in a head of regulated shape and size, and also calculation of durability of rails taking into account existence of fatigue cracks at prevention of complete brittle fracture of all section. The main attention is paid to determination of allowable stresses when calculating cyclic strength, as well as to the accounting of a large-scale factor when calculating cyclic contact strength, and also to determination of duration of development of fatigue cracks and their critical size when calculating durability. The existing normative documents concerning calculations of rails on strength have become outdated and demand development of new ones.

The possibility of increasing motion speeds of express (“Lastochka”) and high-speed (“Sapsan”) electric trains by the side direction of express (project 2726) and high-speed railway (project 2956) switches is experimentally investigated. It is caused by need of reduction of delays in train schedule caused by performance of repair and scheduled works on infrastructure facilities of lines. The basic methodical principle of pilot studies was the integrated approach based on definition of indicators of dynamic qualities and stability of the movement of a rolling stock in a common timepoint (coefficients of dynamic additives on vertical vibrations in steps of spring suspension, frame forces, vertical and horizontal accelerations of bodies of cars), impacts of a rolling stock on rail elements of railway switches (dynamic stresses, side forces), indicators of operability of locomotive crews and comfort of journey of passengers in operational environment. For the purpose of the broadest coverage of possible versions of handling express and high-speed electric trains on railway switches and connected tracks the objects of research were located in even and odd mouths of the station Chudovo of Oktyabrskaya railway; tested EMU was loaded by load simulators according to the scheme of rated passenger density of population. Numerical values of specified indicators are given and the basic possibility of the movement of electric trains on railway switches and connecting tracks with the speeds exceeding the existing standards is proved. By results of tests specific proposals on the updates of the existing normative documents of the Ministry of Transport of the Russia and JSC RZhD regulating operational activity on the lines intended for express and high-speed movement are formulated.

The article presents results of pilot and theoretical studies of JSC VNIKTI in the field of interaction of railway track and a rolling stock and perspective of their application. Questions of longitudinal dynamics in the conditions of different types of braking of trains of increased weight and lengths and their influence on infrastructure are considered. Analysis of dynamic qualities and indicators of impact of model of coupled trainset on track is carried out by means of computer modeling, and impact evaluation of action of longitudinal force on carriage indicators, both dynamic and by impact on track, is given at different conditions of railway track. As a result of testing in 2015 of doubled trains weighing up to 14,200 tonnes at various types of braking the following conclusions were obtained: 1. The considerable array of experimental data on interaction of a rolling stock and way at emergency braking is received allowing a quantitative assessment to this process. 2. When performing asynchronous emergency brakings the “practical top” of the compressive forces in the train (1600 kN) has been for the first time reached and the moment of loss of stability of a rolling stock in a rail gauge has been recorded. 3. When performing synchronous braking sufficient stability of the conducted locomotive and nearby the standing car is confirmed at influence of longitudinal forces. 4. The received results of pilot and theoretical studies can be used for modification of normative documentation for development of local instructions for safe driving of the coupled trains, and furthermore at the organization of pilot trips of the coupled trains of higher weight.

Solving the problem of development of growing volume of traffic in the absence of reserves of available and actual capacity on a number of areas and entire directions necessitates continuous increase of train weight, as well as the use of cars with increased axle load. axle load 25 tonnes wagons is officially adopted in 2013 in Russian railways as the standard. The question of operating cars with axle load 27 tonnes is considered. Comprehensive tests have been started from 2014 at the section of the Oktyabr’skaya Railway Kovdor - Murmansk including evaluation of performance and interaction of the track and cars with axial load of 25 and 27 tonnes in trains of different mass and monitoring the accumulation of track deterioration at the volume of traffic at the level of 10 % in cars with axle load of 27 tonnes with loading capacity at around 14.6 million tonnes gross per year. In these tests was introduced a new element to determine absolute track settling against benchmarks installed out of the track, with the help of high-precision geodetic equipment. Research will be continued in 2016, but already now we can state the following: 1. With the introduction into circulation of heavy trains, including rolling stock of new mass with increased axial loads, it is necessary to evaluate not only the strength of the elements of track superstructure by the first limiting state, but also the intensity of the deterioration in track in general by second limiting state. 2. Handling of heavy train, including cars that have increased axial load, it is advisable to arrange circular routes with corresponding adjustment to the costs on current maintenance and repair of tracks. 3. Factors that take into account the presence of heavy trains and rolling stock with increased axial loads, should be included in the standard documentation, determining the cost of current maintenance of track, including the number of track servicemen, as well as the volumes of repairs.

The present article is devoted to activity of the outstanding Russian scientist, Doctor of Engineering, professor Mikhail Feliksovich Verigo, the founder of large research division - Department “Integrated tests of track and rolling stock interaction”. Scientists and specialists of department took in the past and take nowadays active part in the solution of many problems connected with ensuring scientific and technical progress on a network of the railways of Ministry of Railways of the USSR and JSC RZD. In work only two problems, in which solution the key role was played by M. F. Verigo, are noted: increase of operational speed of passenger trains to 200 km/h and increasing of carrying and available capacity due to use of increased dimensions. The results of the long-term program for the preparation of railways for the introduction of increased dimensions of cars with increased linear load were registered in the new GOST 9238 - 2013 with active assistance of JSC “Russian Railways”. According to this standard one of the larger dimensions - dimension Tpr is already widely used. In particular, the loading gondola cars are built by this GOST, as well as double-decker passenger coaches and others. Dimension Tpr, which was started to develop by M. F. Verigo, has now become a sign of a new generation of innovative rolling stock.

In 2012 - 2015 operational monitoring was carried out to evaluate intensity of lateral wear, depending on operating conditions in the curve of 350 m radius. The article presents data on the influence of operational factors on lateral wear of rails at the East Siberian, South-Ural and Privolzhskaya Railways. It is shown that the main factors affecting the lateral wear are: lubrication, rail canting, curve radius, the level of unbalanced acceleration. To manage the process of lateral wear and reduce its intensity the following should be made: elimination of multi-degree curves; maintaining rail canting within 1/16 - 1/27, thus the elimination of deviations in values of canting should be carried out by replacing the elastic under-rail and under-sleeper pads or by using standard leveling shims; providing well-known engineering solutions, such as design of curves with unbalanced acceleration in the range 0.3 m/s2 for freight and 0.7 m/s2 for passenger trains; lubrication of the rails in curved sections of the track.

In 2013, JSC “Russian Railways” railway network was put into operation high-speed electric multiple unit (EMU) ES1 “Lastochka” of dual supply with asynchronous traction drive produced by Siemens on Desiro platform. In accordance with the requirements of safety standards, and later the Technical Regulations of the Customs Union TR CU 001/2011 “On safety of railway rolling stock” experimental EMUs ES1 and ES2G completed a full range of tests, including their final stage - the complex tests of dynamics and impact on railway tracks and turnouts. The article summarizes the results of comprehensive testing of new high-speed EMUs intended for commuter and regional passenger service. Methodology of the study is based on the works of professor M. F. Verigo and includes experimental determination of combination of indicators of dynamic qualities and impact of trains on railway tracks in the complex tests in a single point in time. Study results of the set of dynamic performance qualities and impact of EMUs ES1 and ES2G “Lastochka” on the railway track with help of experimental and experimental-design methods have allowed to give recommendations on the level of permissible speeds, including run through tangent track sections - 160 km/h; in curved sections with radius of more than 400 m permissible speed can be set in terms of non-exceedance of unbalanced lateral acceleration of 0.9 m/s2, in curves of radius less than 400 m - in terms of non-exceedance of unbalanced lateral acceleration of 0.7 m/s2. On the basis of this combination of indicators with Norms of calculation of the strength of railway tracks a table of permissible speeds for trains is defined, which, as a normative document of JSC “Russian Railways”, introduced in the areas of circulation of these trains.

Russia’s first research unit - department “Integrated tests of railway rolling stock and track” was created in VNIIZhT in 1962 on the initiative of Professor Michael Feliksovich Verigo to establish the permissible speeds of new rolling stock. Modern promising conditions in rail transport, characterized by the ever-increasing force influence of train on the infrastructure, require greater attention of the experts to the one of the fundamental and multi-sided problems - interaction between track and rolling stock. The article presents a retrospective analysis of formation of VNIIZhT research activities in this field. Author considers fruitful combination of theoretical and experimental studies aimed at solving urgent problems of increasing traffic safety and development of the increasing volumes of traffic. Priority tasks that will reduce the existing gap in the development of traffic on the busiest domestic and foreign lines was formulated. It was concluded that the improvement of the conditions of interaction between track and rolling stock, combined with the ongoing JSC “Russian Railways” activity on specialization of lines will significantly increase the volume of traffic on the existing congested lines with shift of investment costs to the construction of additional main tracks.