Introduction. The significant development of automation and telemechanics systems, which caused a variety of operating modes of single-track lines, requires a more detailed study of the potential of interval control systems for more efficient transport. The object of the study is the transport process on a single-track line. The subject of the study is the potential of train interval control systems to increase throughput and carrying capacity instead of building second main tracks. The study intends to determine an effective performance range of interval control on single-track lines.

Materials and methods. The study involved a multi-approach simulation, including a process approach to simulate the work of on-duty personnel, agent-based simulation for train mode selection and system dynamics for traction calculations. Different operating options for a single-track line under destabilising factors were assessed using the game with Nature strategy. The paper proposes a new approach to assessing interval control through the creation of an equal economic solution sphere of interval control use and construction of second main tracks.

Results. Simulation model runs created matrices of indicators and configurations, and different operational strategies on a single-track line were assessed using game theory criteria. The Anaconda Coordinate Interval Control System has proved to be the most effective way to reduce the need for second main track construction. The paper presents an equal economic solution sphere of feasible use of interval control and construction of second main tracks.

Discussion and conclusion. The proposed method of selecting the most feasible interval control system on a singletrack line based on the creation of an equal economic solution sphere in combination with the game with Nature could be used to rationalise the allocation of railway transport investment. The conclusions from its application do not contradict the theory of traffic flows and reduce uncertainty in the development of single-track line infrastructure.

Introduction. Overhaul of railway track and routine maintenance of infrastructure requires interruptions in train traffic. This has a major impact on transport and at the same time is an integral part of it. Allocation of interruptions in traffic is based on the prioritisation of clearance for trains, which often complicates repairs of a given scope. The article considers ways to streamline break scheduling for railway repairs on heavy-traffic routes.

Materials and Methods. The research is based on the known theories of operational management of transportation, applied technologies of infrastructure repair, statistics of clearance for trains, repair scopes and variable train schedules. The paper uses methods for calculating the capacity of space intervals under repair, and theoretical justification of analytical formulas for calculating clearance for trains.

Results. The paper highlights calendar periods and redefines traffic capacity indicators and their calculation methods for determining the annual average daily throughput capacity. The article plots possible track overhaul schedules with different durations and different interruption patterns (breaks). The work shows the dependencies of the total duration of breaks and total clearance for trains during a calendar year under different repair patterns for selecting a variant under given conditions.

Discussion and conclusion. These dependencies help streamline the repair programmes considering repair volumes and clearance for trains at the scheduling stage. Automation of the process optimises labour costs for scheduling repairs.

Introduction. The most popular design solutions for bridge crossings on railways are either girder structures with a suffciently high cross-sections located below the train load application level, or trusses whose height depends on the span length and more often than not far exceeds the height of the railway clearance. This motivates to consider design solutions that utilise the space immediately around the transport dimension without increasing the cross-sectional height from below or above the plane of application of the dynamic load. Since the cab exerts a variable and highly cyclic load, control of compressive and tensile stresses will be required at the top and bottom of the spanwise cross-section. The work attempts to justify the use of the geometric space immediately adjacent to the contour of the vehicles in the design of the transverse profile of the span structure.

Materials and Methods. Authors determined the stress deformation of the beam span by analysing the bending moments and extreme normal stresses to select concrete reinforcement or steel beam geometry. The evaluation criteria are normal stresses, which could be compressive or tensile depending on the location of the wheel pairs on the impact lines.

Results. The paper analyses the existing approaches to evaluate the inclusion of cross-sectional elements of a girder structure located above the plane of wheel load application (e.g. ballast bed sides). The analysis provides graphical relationships for the moment of inertia of a cross-section with different geometries, which is actually a target function that relates the  geometric dimensions of the girder span along and across the cab movement to the principal stresses and determines the optimum position of the load application surface relative to the top and bottom of the cross-section.

Discussion and Conclusion. This approach is suitable for both open H-beam sections and box sections with sides currently widely used in the design of bridge crossings for high-speed railway lines. A significant effect could be achieved due to higher span sides and the location of the lower shelf of the cross-section box. Multi-level interchanges at the same span dimensions allow the proposed design solutions to reduce the distance between the levels of mobile load application.

Introduction. Scientifically, energy efficiency of shunting operations at electrified stations should be improved by gradual replacement of diesel shunters with advanced contact-accumulator electric shunters. The discussion of the use of such locomotives should take into account the power consumption figures achieved by mainline electric locomotives of the existing series in shunting operations.

Materials and Methods. The paper uses statistical methods to analyse power consumption on driver’s routes for 2023 and processes registered on-board data of electric locomotives involved in shunting operations for individual driver’s shifts. The work investigates the relationship between power consumption for shunting operations and atmospheric air temperature. 

Results. The paper determines the peculiarities of power consumption in shunting operations of electric locomotives, and provided power consumption figures in operation of different series of electric locomotives. The work considers the air temperature factor when rationing electricity for shunting, and proposes an on-board data based procedure for power consumption rationing.

Discussion and Conclusion. The study indicates the range of power consumed by electric locomotives for shunting operations under current operating conditions. This wide range of shunting loads should be taken into account in the design of advanced electric shunters. The need for their creation is also caused by the incomplete correspondence between the characteristics of the mainline electric locomotives used and the shunting conditions. The latter also calls for a reasonable choice of the most suitable series for shunting work.

Introduction. The currently used turnout switches geometries provided for the development and serial production of the main types of turnout equipment that ensure the transport process on the Russian railways. Further development of the infrastructure and the turnout facilities as its most important component calls for new, more advanced turnout switches geometries that take into account higher requirements for train speeds, dynamic loads and passenger comfort. The study develops geometries for the most common turnout equipment.

Materials And Methods. The conditions of rolling stock movement along turnout switch are evaluated in terms of associated kinematics: travelling speeds, accelerations and the change rate of these accelerations. The developments in this article are based on the analysis of the cab kinematics moving along straight and branch tracks of turnout switches considering their properties and differences from the movement along curves on space intervals.

Results. The proposed turnout switches have obtained data on unbalanced acceleration, energy loss, equivalent design speed and others. The paper offers design solutions to change turnout switches geometries that affect passenger comfort and provided the basis for the design of turnout geometries with a smoother rolling stock run.

Discussion and Conclusion. An analysis of turnout switches geometry developments that smoothen rolling stock movement on turnout switches and improve passenger comfort identifies four engineering solutions recommended for implementation as providing the highest efficiency at the lowest cost of installation and operation on the Russian railway network. These are two variants of 1/11 turnout switches with tangent switch curves interchangeable with the turnout switches currently widely used on Russian railways, and two more gentle variants of 1/13 turnout switches. The engineering solutions developed under the same methodology are also recommended for 1/9 and symmetrical 1/6 turnout switches.

Introduction. The study is intended to provide guidelines to reduce the machining time of locomotive wheel pairs by analysing the design and performance of existing types of wheel turning and milling lathes of domestic and foreign production in locomotive service depots. The observed growth in traffic intensity and volumes on Russian railways requires ensuring reliability and improving the performance of locomotives. The wheel pair is one of the most metal-intensive and critical elements of the undercarriage. The wheel and rail interaction causes a range of physical and mechanical phenomena inflicting intensive thermomechanical damage on the tyre tread surface: undercutting of the ridge, rolling, slides. Removal of tread surface defects requires turning the wheel pair on machine tools, until the required initial profile is obtained, which is a time-consuming process. Therefore, an important task is to minimise turning costs, which requires the use of the newest technological solutions implemented in new machine-tools, including imported equipment.

Materials and Methods. The article analyses global machine-tool industry trends and their impact on the machinetool market in Russia and considers types, models, comparative characteristics, experience in operation, maintenance and repair of locomotives using wheel turning and milling machines by 96 locomotive service depots in 13 branches of LocoTech-Service LLC.

Results. The paper examines the fleet of wheel turning machines (types, design, condition), calculated the load of the machines, and considered foreign-made analogues. A numerically controlled mobile wheel turning machine with a profile design has been developed based on locomotive service depot re-equipment needs and wheel turning market data.

Discussion and Conclusion. The work identified the bottlenecks of the machine fleet operation and provided data on its obsolescence and selection of analogues from foreign manufacturers. Domestic machines are more adapted to Russian operating conditions, foreign models have advantages in numerical control systems. The paper proposes a number of design and technological, staff training, and production organisation measures to eliminate bottlenecks in wheel pair machining.

Introduction. A number of railway lines in Russia experience increased traffic volume. The lines with the fastest annual growth are the Eastern Polygon, Transsib and BAM sections. Higher volumes of trailing load, especially in limited trafficcarrying capacity, entail longer and heavier trains and higher axle loads, which puts more strain on the existing railway infrastructure, especially the tracks. This intensifies the interaction in the wheel — rail system, further increasing track load and damage rates. This paper is intended to identify the correlation between operational factors and track load indicators.

Materials and Methods. The study of the actual damage rate on the network and the Eastern Polygon sections involved automatic devices collecting wheel — rail interaction data for several months and determined the laws and parameters of their distribution.

Results. The analysis of distribution parameters showed large variation (45–55% for average values and up to 300 % for dispersions). A similar variation was obtained for the accumulated damage and resource exhaustion rates on the investigated track sections. The work also reveals a high dependence of damage rate (from 40% and above) on the  dynamic qualities of the rolling stock determined by its design and condition. 

Discussion and Conclusion. Structural and maintenance solutions for tracks with particularly high usage require constant monitoring and analysing of the loads in the wheel — rail system. This approach would improve track design and maintenance based on the operational characteristics of specific lines for safer traffic and more efficient track maintenance and repair costs.