Station Tracks Research Articles

ФОРМИРОВАНИЕ ОБЪЕКТИВНЫХ ПОКАЗАТЕЛЕЙ РАБОТЫ СОРТИРОВОЧНОЙ СТАНЦИИ НА ОСНОВЕ ДАННЫХ «ОТ КОЛЕСА»

The paper presents a new principle for forming freight marshalling yard indicators based on the use of data from various reading devices and sensors located on the station tracks (data “from the wheel”). The paper shows the relevance and objectivity of using the proposed approach, implementing the presented principles for obtaining real freight yard indicators. The implementation is presented on the basis of data generated by the system for monitoring and preparing information on the movements of wagons and locomotives at the station in real time. The difference between the results obtained as a result of implementing the proposed approach and the information generated in real certificates and reporting journals of Russian Railways JSC is shown. Hypotheses-descriptions of the difference between information “from the wheel” and information obtained by manual input of data on the movements of cars and locomotives are proposed. The conclusion describes further prospects for automation of calculation and forecasting of station operation based on data “from the wheel”.

Railway track settlement patterns and control measures for multi-tunnel construction underneath a station track group: a case study

This paper is based on the proximity engineering project of the Baishiyi tunnel group passing under the Chongqing West Station track group. Considering the train load and the spatial relationship of the tunnel and track groups, the settlement patterns, horizontal displacement, and differential settlement of the tunnel–strata–tracks system during the excavation process are studied through theoretical calculations and numerical simulation methods. The results indicate that the tunnel vault, strata, and track settlement deformation patterns are similar. Throughout the tunnel construction process, the tracks underwent uplift, settlement, and eventually stabilized. The settlement trough formed by the excavation of the three tunnels below the track group has an impact range of 25–145 m. Between 35 and 75 m, the differential settlement of the double track gradually increases with excavation. As the tunnel face reaches 75 m, the track differential settlement gradually converges and tends to stabilize. To minimize the impact of underpass tunnel construction on track groups, it is recommended to use a combination of full-section hole grouting and surface reinforcement grouting for ground reinforcement. Additionally, optimizing the construction parameters, including the step length and primary support closure time, and strengthening the locking anchor can further reduce the impact.

Optimization study of station track utilization in high-speed railroad based on constraints of control in random origin and process

Optimization study of station track utilization in high-speed railroad based on constraints of control in random origin and process

Automatic braking system for spontaneously departing rolling stock on station track

The current state of the use of methods of stopping wagons on railway transport in cases of their spontaneous departure is investigated. As a result, it was found that cases of spontaneous departure of rolling stock on railways in the region of the Republic of Uzbekistan account for 4.2% of the total share of traffic safety violations and account for 19.9% of the damage caused. This article highlights that in order to prevent the above situations, after installing brake shoes through automatic braking, a device on a spontaneously departing rolling stock, taking into account the number of wagons and their state of loading, based on the development of a mathematical model for determining the stopping distance, a system operating without a human factor was created and introduced into production.

Functions of the interlocking system on mixed traffic lines

These days, automated rail traffic control systems help to lessen the need for human intervention in train traffic management. On the other hand, the various algorithms used by interlocking systems to coordinate the movement of trains belonging to distinct categories result in longer wait times for technological procedures at the station. The possibility of timely routes for trains of multiple categories occurs by employing the method of automatic route preparation by interlocking systems in the organization of the movement of trains of different categories. In interlocking systems, automatic route preparation can be achieved by continuously monitoring train characteristics, train traffic graphs of various train classes, and the condition of equipment involved in the function’s development. Nonetheless, it is predicated on the creation of many models to arrange the specifications of various train classes and train movements inside a single schedule type. In order to prepare the routes ahead of time for the station tracks based on the algorithms for the operation of interlocking systems for various kinds of trains, the paper analyzes the reliance of the traffic composition characteristics.

Цифровые технологии пропуска по перегонам и станциям — основа организации движения на Московских центральных диаметрах

train separation, automatic block system, ABTC-MSh system, moving block, interlocking, automatic cab signalling, train control system The article discusses the development of automatic block systems, which form the basis of separation systems. It also highlights the key factors limiting the capacity on open lines, and ways to solve them. A brief overview of the foreign experience of the organization of train separation using automatic block system based on track circuits is given. The article shows the capabilities and role of the computerbased automatic block signalling system with a centralized placement of equipment, audio frequency track circuits and duplicating information transmission channels as an important element of the train traffic management at the sections of Moscow Central Diameters. The significance of the implemented non-stop passage of trains along the main station tracks providing substantial section capacity increase is demonstrated. The necessity of building a digital system for train spacing is shown, which makes it possible to implement the moving block technology with-in the station ensuring the movement of trains on open lines and at stations with the same headway. The advantages of a new type of the computer-based automatic block signalling system as a basic element of a promising Russian train traffic control system and the positive effects of its implementation on the Russian railway network are indicated. The direction of development of train separation systems is outlined within the framework of further digitalization.

Tomographic Reconstruction of Atmospheric Water Vapor Profiles Using Multi-GNSS Observations

Continuously operating reference stations (CORS) provide augmentation services for the highly accurate, cm-level GNSS positioning needs of land surveyors, agriculture, and even autonomous vehicles. These stations have accurate coordinates, thus they can be used to estimate the signal delay caused by the neutral atmosphere including the atmospheric water vapor. The estimated zenith wet delay (ZWD) is in a close correlation with the integrated water vapor in the atmospheric column. Since a ground station tracks several satellites at every epoch, one could also estimate the slant tropospheric delays, which can provide information on the spatial distribution of the atmospheric water vapor, too. This paper introduces a near real-time multi-GNSS processing approach to estimate slant wet tropospheric delays and a coupled tomographic reconstruction technique to estimate the 3D wet refractivity model that can be assimilated in numerical weather models. The estimated zenith tropospheric delays (ZTDs) and tropospheric gradients are used to restore the slant wet delays (SWD) affecting the observed satellite-receiver range. The SWDs are used as input for a tomographic reconstruction algorithm providing the wet refractivities in a pre-defined voxel model. The derived refractivity profiles have been validated with radiosonde observations. The results show that our GNSS tomography approach could reconstruct the refractivities with the uncertainty of 10 ppm below 3 km of altitude and of 0.3 ppm at the altitude of 10 km in terms of standard deviation.

A Multistage Decision Optimization Approach for Train Timetable Rescheduling Under Uncertain Disruptions in a High-Speed Railway Network

Railway operations are vulnerable to unexpected disruptions that should be handled in an efficient and passenger-friendly way. This paper focuses on a real-time train timetable rescheduling problem in a railway system with a seat-reserved mechanism during disruptions. An integer linear programming model with a compensation mechanism is established to provide a better overall solution for dynamic and multistage rescheduling problems. The main part of the model considers the strategies of retiming, adding train stops and reordering to reduce the impact of passengers, while the compensation mechanism part mainly deals with the uncertainty of disruption durations. The related constraints mainly include section track capacity, station track capacity,passenger transfer rules and some robust measures under the uncertainty of disruption durations. A multistage decision optimization framework is established, and a rolling horizon algorithm is embedded in it to approximate the desired optimal solution. A series of numerical experiments based on a real case of China’s high-speed railway subnetwork are carried out to verify the effectiveness and efficiency of the proposed optimization approach.

Production estimate of technological operations duration in railway transport

Purpose: To stabilize the departure of trains on schedule, to do this, to justify the size of the factor of unevenness taken into account when normalizing the duration of the main technological operations with the compositions of container block trains for departure at the junction stations. Methods: From the existing automated systems, statistical data were collected and processed using MS Excel software, and the mathematical expectation, standard deviation, and dispersion of the duration of operations with the block train at the departure station were determined. The hypothesis about the normal law of distribution of the random variable of the duration of each of the main operations at the station was tested by the “chi-square” goodness-of-fit test. Results: The distribution of the random variable of the duration of operations at the station is described using the normal distribution law; a technological schedule for processing the composition of the container block train on the tracks of the railway junction station was built. Practical significance: Practical recommendations will reduce the technological norms for the processing time of a container block train on the tracks of a railway junction station. As a result, the processing time for block trains on departure on the station tracks will be reduced from 154 minutes to 132 minutes, which will save time by 22 minutes.

Improvement of accident prevention measures in cases of spontaneous derailment of railway rolling stock

There has been researched on railway station tracks to determine the method of automatically stopping motion content in cases where Motion Content has gone away on its own. Even today, there are mainly cases of spontaneous movement of the composition of the movement to the side where the slope of the Railway Station roads decreases. This leads to many casualties and accidents caused by the spontaneous movement of trains at railway stations. By applying the proposed method of automatically stopping the rolling stock without human intervention, the law of conservation of mechanics, and determining the number of brake shoes set by the system device, the losses that may occur in stopping the rolling stock are achieved. In addition, the features of equipping the places of automatic stopping of the rolling stock with devices in the case of rolling stock leaving by themselves on the existing railway station tracks were considered. Also, the algorithm of operation of the system for automatic stopping of the moving parts that have gone away on their own is given of this system safety to determine semi-Markov chain for based on the system a mathematical model of safety was created. Microprocessor to the system based on by itself gone the rest movement contents to stop intended automated from devices use there is a niche in the station ways account received devices without work to algorithms and trains movement speed mutually dependence provided without by itself moving gone movement units safety provide through accidents took is taken. This prevents potential accidents, increases the reliability of system use, and leads to cost-effectiveness in system use.

Разработка алгоритма расчета наибольшего приведенного уклона при закреплении вагонов на путях станций тормозными башмаками

Purpose: The development of machine-friendly calculation algorithm of maximum average (reduced) slope for to define minimal norms for securing cars, groups of cars or train stocks that’re left on station railways without locomotives. Methods: The set task solving was held by making up the succession of mathematical and logical actions. Mathematical expressions describe flattening of track longitudinal profile, i.e. the calculation of reduced slope. Logical actions describe limitations at pursuing the calculations. Results: Calculation algorithm of reduced slope has been made up which takes into account the provisions of Instructions on Train Motion and Shunting Work on Railway Transport of the Russian Federation. Practical significance: The developed algorithm allows to pursue the calculation of reduced slope at the least favorable conditions of the placement of cars, group of cars and stocks of trains in the frames of effective length of station tracks that corresponds to provision conditions for rolling stock securing from leaving. The pursued research allows to develop program for defining minimal norms for securing cars, groups of cars and stocks of trains that’re left on station railways without locomotives, in full accordance with Instructions on Train Motion and Shunting Work on Railway Transport of the Russian Federation.

Anomaly Detection of Metro Station Tracks Based on Sequential Updatable Anomaly Detection Framework

The intrusion of foreign objects in tracks, one of the sources of injuries and fatalities in metro stations, can be solved as an anomaly detection task. However, the existing anomaly detection methods rarely consider the importance of updating the new knowledge from false alarm data, resulting in repeated mistakes. These methods are also impractical for edge devices that cannot afford the high calculation cost. A sequential updatable anomaly detection (SUAD) framework is proposed to tackle these problems. This framework is based on the Robbin-Monro algorithm and a fast version of Mahalanobis distance. A well-trained model of SUAD can continue to learn new knowledge through the sequential knowledge update module based on the Robbin-Monro algorithm without reviewing the old data. SUAD utilizes a new Mahalanobis distance calculation method based on principal component analysis. This new method exhibits a fast inference speed with a lighter model size than before. SUAD is evaluated on a self-built Metro Anomaly Detection (MAD) dataset and three public datasets. SUAD achieves an average area under the receiver operating characteristic curve score of 99.4% at image level and 99.6% at pixel level on MAD. SUAD also reduces at least 78% model size and 60% memory usage. Competitive results are also achieved in public datasets, including MVTec AD, beanTech Anomaly Detection, and CIFAR-10.

Impact of Change of the Interlocking on the Acceleration of Railway Transport: A Case Study from the Podbrezová Railway Station

Accelerating rail transport is a key factor in improving the quality of passenger and freight transport. The main research question of the article asks whether it is possible to increase the speed due to the change in the interlocking. The main research tool is a comparison of the interval of crossing before and after the reconstruction of the interlocking. As the entire research is carried out on a single-track line at the Podbrezová station, the interval of crossing is the most relevant indicator. An associated goal of the entire research is to point out a possible increase in the carrying out of station tracks and an overall improvement in the working conditions of operational staff (station inspectors and switchmen).

A Computational Approach to Overtaking Station Track Layout Design Using Graphs: An Extension That Supports Special Turnouts—An Improved Alternative Track Layout Proposal

The author recently designed, developed and implemented in Maple a package based on the use of digraphs that analyses the connectivity of an overtaking station on a double-track line. It was used to propose an alternative track layout for this kind of station, with advantages over the track layouts usually adopted. However, that package could only deal with “standard” turnouts (but neither with crossings nor with “special” turnouts, such as “single slip turnouts” or “scissors crossings”). This new article presents an improved version of the package. It uses a trick consisting in including virtual vertices in the associated digraph that are dead ends. This way it is possible to include the “special” turnouts in the track layout. It makes it possible to evaluate different alternative track layouts, including “special” turnouts; and to finally find one track layout that has advantages over the standard one and over the one proposed in the previous article. Let us observe that the design of the track layout is key for the exploitation of the infrastructure. In fact, the Spanish infrastructure administrator is nowadays remodelling the track layout of some of its main railway stations, as well as other smaller facilities.

A Study of Wagon Turnaround in the Current Context

Wagon turnaround remains the key performance indicator of railway transport operations characterizing the efficiency both of a wagon fleet owner and of “Russian Railways” Company (RZD). Freight logistics efficiency in the railway sector can also be assessed using this indicator. For determining the wagon turnaround time, the duration of operations at technical stations, freight handling time and the time in motion are taken into account. “Russian Railways” company and operator companies control the three components of the wagon turnaround time. The synergies of railways, intermodal types of transport, and private railways belonging to major freight owners are of particular interest. Their interaction efficiency can be calculated using the wagon turnaround formula that considers the freight idle time and the local operations factor. The local operations at the station for serving private tracks and port sidings are regulated by a number of documents that determine the procedure for supply and departure of wagons, the number of wagons in supply, the regularity of these operations, the number and series of shunting locomotives, etc. The optimal number of wagons in supply will be determined by the minimum cost of wagon movement and wagon idle time on the station tracks. The calculation of the cost function sensitivity will make it possible to determine the limits in the optimal wagon movement changes.

A Study on the Influence of Rail Top Smoke Exhaust and Tunnel Smoke Exhaust on Subway Fire Smoke Control

The special emergency plan for subway fires in China stipulates that when a fire occurs at a train stop, it is necessary to confirm whether the fire mode of the tunnel ventilation system is implemented. Because of the setting mode of tunnel ventilation and smoke exhaust in the station track area, the smoke exhaust at the rail top and tunnel cannot operate at the same time. To study the influence of rail top smoke exhaust and tunnel smoke exhaust on subway fire smoke control when a train stops at a station, we take an island station as an example. A 1:1 full-scale numerical model is established to study the smoke spread area, temperature field distribution, and carbon monoxide concentration. The results show that when a train fire occurs in a subway station, the rail top smoke exhaust mode has the best smoke exhaust effect compared with the other three smoke exhaust modes. In this mode, the smoke diffusion in the carriage is the slowest and the available escape time of personnel is the longest. Therefore, it is recommended to adopt the rail top smoke exhaust mode in case of train fire in the subway station; that is, open the smoke exhaust outlet on the rail top for smoke exhaust, and organize personnel to evacuate to the safe position of the platform through the connecting channel and escape exit. If conditions permit, local small fans can also be added to meet the requirements of smoke exhaust. The research results can provide guidance for the emergency plan and provide strong support for promoting the improvement of the fire emergency plan.

The combined model of express assessment influence of the objective specializations for station track capacity including infrastructure parameters

The combined model of express assessment influence of the objective specializations for station track capacity including infrastructure parameters

Vulnerability Analysis of Urban Rail Transit Network by Considering the Station Track Layout and Passenger Behavior

The vulnerability of an urban rail transit (URT) network is an index that reflects its ability to cope with risks. However, existing URT network vulnerability studies have paid less attention to station track layout and passenger choice behavior, both of which significantly affect the consequences of a disruption incident. In the present study, we first analyze an actual scenario of URT section disruption and passenger behavior during an incident. Then, we propose two section vulnerability indexes that quantitatively evaluate the effect of a URT section disruption from two aspects: detour delay and loss in passenger flow. To make the application scenario of this method more realistic, the track layout and depot location are taken into account. By considering the relationship between train routing and the sections, a concept of “dominant section” is put forward to make the calculation of the vulnerability indexes more efficient and can be used for a simultaneous multi-section-disruption scenario. Finally, a case study of the Beijing Subway network is provided. The results show that disruptions in only a few critical sections can significantly affect the URT network passenger flow. Disruption of only 3% of the sections can lead to 80% passenger-flow loss, which reflects the high vulnerability of URT networks. The method proposed in this paper can provide support for the evaluation of URT network performance.

КОМПЬЮТЕРНОЕ МОДЕЛИРОВАНИЕ ДИНАМИКИ ВЗАИМОДЕЙСТВИЯ КОЛЕСНЫХ ПАР ВАГОНОВ С ТОРМОЗНЫМИ БАШМАКАМИ

The paper considers the problem of keeping cars from rolling away on station railway tracks with a permissible slope of 0–2.5 ‰. The study presents the computer simulation results for the dynamic interaction of wheels with brake shoes installed on rails in the process of stopping a freight train car using standard brake shoes in the MSC.ADAMS engineering software package. In this case, various properties of the rail surface were taken into account, simulating favorable and unfavorable conditions for contact between the wheel, brake shoe and rail at braking due to both weather conditions and the peculiarities of station tracks location and operation. The interaction of the car wheels with the maximum axle load and the station brake shoes installed on the rails was studied at different initial velocities of the vehicle movement, as well as when it is at rest on tracks with the permissible slope under the conditions of ensuring the minimum friction between the wheel and the rail, as well as the interaction of rail and shoe was analyzed, which corresponds to the presence of the train on oily rails. It is demonstrated that it is not always possible for one brake shoe put on the oily rail to hold the train moving with the initial velocity more than 0.5 m/sec. Under other conditions of the wheel-brake shoe collision, the problem of keeping the train on the rails is also possible, due to such random factors as lateral wind load, rail icing, wear and deformation of the wheel surface and brake shoe, which reduce the dynamic friction coefficient between the contacting surfaces.

Обоснование реконструкции контейнерной площадки

Objective: Having studied the features of container train compositions and the container storage conditions in an open area, to propose measures for the station modification and perform a few calculations demonstrating the feasibility of the proposed measures. Me¬thods: Methods of the general systems theory, system and economic analysis, terminalistics, logistics, and railways opera-tional ma¬nagement have been applied. Results: Two alternative options for the development of a container station are proposed, considering the features of the logistics facilities’ evolution and the theory of terminalistics: extension of the railway track and widening the station for storing high-capacity containers by 20 meters. The technology of container train composition on station tracks is considered. The performance of container train composition is calculated taking into account the technology chan¬ging. Practical importance: The increased capacity of the container station opens up new opportunities for the development of a promising container traffic at the station under consideration and, consequently, for the growth of profitability of the terminal and logistics busi-ness of JSC Russian Railways. The study findings can be applied in the implementation of the con-cepts for the development of the container business of the Russian Railways Holding, the creation of a network of terminal and logistics centers in the Russian Federation, as well as in the design of individual elements of the terminal and warehouse infrastructure and optimization of the container train servicing processes.