Current Railway Research Articles

Flagging Off High-Speed Trains in India: Prerequisites, Feasibility, Benefits and Challenges

The paper is an attempt to answer the convoluted riddle: how can India achieve global standards in high-speed railway infrastructure? The need for overhauling the current railway network is conspicuous. With dull patchy walls of railway stations daubed in paan spits, railway tracks rusting with age and train compartments reeking with stench; a travel in the Indian Railways could be a possible nightmare for many. The rot runs deep in the system: it is running in huge losses. The Indian Railways suffered a loss of nearly Rs. 25,000 crore the previous fiscal year. A comprehensive analysis of the issues riddling the network and suggesting solutions thereto are prerequisites to inducting high speed railways to the network. Introducing high-speed railways in the network without thought to the existing problems is meaningless. The paper shall commence with cataloging the issues plaguing the railway network with relevant suggestions. After addressing the issues, the paper would continue to chart a road-map for successful introduction of high-speed railways in India. The costs involved in the project along with possible routes shall be discussed. The paper would conclude with juxtaposing the benefits of the high-speed system with the challenges arising therefrom.

Characterization of railway line impedance based only on short‐circuit measurements

SummaryThis paper presents a new methodology to obtain the line impedance of current railway tracks by using only short‐circuit measurements. Open‐circuit measurements required by conventional methodologies are discarded, since they cannot be carried out for railway tracks in service (electrically continuous and indefinite length). The mathematical basis of the proposed methodology is based on the transmission line theory but focused on the changes in track length. The proposal has been successfully applied to characterize the impedance of the high‐speed railway line at the Spanish AVE Madrid–Valencia (Cuenca) and in the AVE Atocha–Chamartin tunnel (Madrid). Copyright © 2014 John Wiley & Sons, Ltd.

High-speed train control based on multiple-model adaptive control with second-level adaptation

Speed uplift has become the leading trend for the development of current railway traffic. Ideally, under the high-speed transportation infrastructure, trains run at specified positions with designated speeds at appointed times. In view of the faster adaptation ability of multiple-model adaptive control with second-level adaptation (MMAC-SLA), we propose one type of MMAC-SLA for a class of nonlinear systems such as cascaded vehicles. By using an input decomposition technique, the corresponding stability proof is solved for the proposed MMAC-SLA, which synthesises the control signals from the weighted multiple models. The control strategy is utilised to challenge the position and speed tracking of high-speed trains with uncertain parameters. The simulation results demonstrate that the proposed MMAC-SLA can achieve small tracking errors with moderate in-train forces incurred under the control of flattening input signals with practical enforceability. This study also provides a new idea for the control of in-train forces by tracking the positions and speeds of cars while considering power constraints.

Seismic Assessment of the Milano Centrale Railway Station

This study of the Milano Centrale railway station aimed at assessing the seismic vulnerability of the monumental building. The work was carried out on the occasion of a big project to refurbish the station, including both the restoration of certain areas of high artistic value and the improvement of functionality with the current railway services. The seismic analysis is focused on the monumental part of the building, including the Coaches Gallery, the Tickets Hall, and the Head Gallery. The safety level of the structure was assessed on the basis of comprehensive historical investigation, survey, testing, and finite element analysis. The issue of checking the seismic safety of a large number of members is addressed using a step-by-step verification strategy. The results of the study show that the overall safety level of the structure is acceptable, although some local structural deficiencies need to be handled with a proper strengthening design.

Research on Value Chain of China's Railway Oil Supply Chain

The efficient and economic organization of railway oil supply is very significant to reduce operating costs and ensure the safety. This paper introduces the processes of China's railway oil supply system and uses value chain model to analyze current railway oil supply pattern by analyzing the value activities and value orientations, points out the problems, proposes the optimization directions and adjustment recommendations. It provides the revolution of China's railway oil supply system with a basic direction.

Long term evolution in high speed railway environments: Feasibility and challenges

Long Term Evolution (LTE) is considered to be the natural evolution for the current Global System for Mobile Communications-Railways (GSM-R) in high speed railway environments, not only for its technical advantages and increased performance, but also due to the current evolution of public communication systems. In railway environments, mission critical services, operation assistance services, and passenger services must be supported by reliable mobile communication systems. Reliability and availability are key concerns for railway operators and as a consequence, railway operators are usually conservative adopters of information and communication technologies (ICT). This paper describes the feasibility of LTE as a successor to GSM-R for new railway mobile communication systems. We identify key features of LTE as a technology and analyze its ability to support both the migration of current railway services and the provisioning of potential future ones. We describe the key challenges to address specific requirements for railway communication services including the provisioning of voice service in LTE networks, handover performance, multicast multimedia transmission, and the provisioning of group communications service and railway emergency calls.

Austenite Grain Size Evolution in Railway Wheel During Multi-Stage Forging Processes

The knowledge of microstructure evolution of railway wheel during hot forming process is the prerequisite of improving mechanical properties of the final product. In order to investigate the austenite grain size evolution of railway wheel during multi-stage forging process, mathematical models of recrystallization and austenite grain growth were derived firstly by hot compression tests for railway wheel steel CL50D, which then were integrated with a thermal-mechanical finite element model by the developed subroutines. The information about kinetics of recrystallization and grain size distribution during the forging process was obtained by simulation. The predicted results were validated by experiments in an industrial scale, and the average error between the predicted grain sizes and the measured ones is about 5%. The result shows that, under the current railway wheel forging process, the grain size distribution after final forging is inhomogeneous extremely. There is a narrow coarse grain zone between the external part and center of the hub caused by Static recrystallization after final forging. With cooling of 60 s after final forging, the grain size is about 85 μm for the areas near the web surface and 175 μm for center areas of the hub and rim.

Power Evaluation of Jakarta DC Railway Substation to Meet 1.2 Million Passengers Per Day

Abstract Jakarta is a metropolitan city that continues to strive to develop the capacity of its mass transport as other large cities in the world, primarily the development of the rail-based transportation. Indonesia Railway Company (PT Kereta Api (Persero)) had forecasted that there will be 1.2 million passengers per day on Jakarta in 2019. To meet these targets, it is necessary to adequate the infrastructure planning, especially the capacity of the DC substations which supply the electric power to the trains. This paper will demonstrate the strategy used to determine the point of placement of new DC substation and/or existing DC substation upgrades throughout the Jakarta area from 2013 to 2019. The current railway timetable and the future pattern of railway operation plan are used to predict the possibilities of peak load spots along the track.

Standardized Management of China Railway Emergency Plan Strategic Ponder

Abstract At present, railway emergency plan management system has become the important support to maintain the normal operation of railway transport system in the foreign developed countries. But our country was far behind in emergency management system, and the emergency system is still not perfect. It's already cannot satisfy the current railway transport development needs. This paper analyzes the present situation of China railway emergency plan, and puts forward China's railway emergency plan standardization management strategic thinking in view of the existing problems.

Design of Wireless Power Transfer System for Railway Application

As wireless power transfer (WPT) technologies emerge in a wide range of applications including public transportation, many expect that applying the technology to the current railway systems will bring positive effects to current railway systems. In this paper, we introduce design methodology of a WPT system for railway application. Fundamental principles of magnetic fields and a WPT circuit are first analyzed, and advantages and efficiency of a possible train system are discussed. It then examines other significant factors such as performance requirements and EMC criteria to design a wireless train system.

CBTC시스템과 WPAN시스템의 상호간섭영향 및 간섭신호 억제방안에 대한 성능분석

The CBTC(Communication based Train Control) and WPAN(Wireless Personal Area Network) systems employed on 2.4GHz ISM band wireless networks provide complementary service within the same environment. Coexistence between the networks will be impaired if the mutual packets are uncertainty associated the timing or gaussian distance. This paper analyzes the impact of the mutual interference and proposed method to minimize the effect of the WPAN system signals on CBTC system. The performance analysis is illustrated by examining the symbol error rate versus signal to noise interference ratio in terms of carrier frequency offset. The method contributes to reduce the symbol error rate drastically. However it can`t be a fundamental solution for the impact on the interference problem. It may be needed for railway only frequency after checking the problems of the current railway frequency.

European integration and national models for railway networks (1840–2010)

Following the assumption that history is one of the main factors conditioning transport systems, this paper analyses the evolution of railways in Europe since 1840 and aims to provide a better understanding of present infrastructures and future challenges. The central message is that states played, and continue to play, a fundamental role in the establishment of Europe’s national railway networks, regardless of EU guidelines. As a consequence, every national transport system has exhibited a series of specific characteristics throughout its history and these must be identified if we are to improve the construction and coordination of current railway networks and their services.Railways played an important role in the process of state formation from the mid 19th century onwards, and have continued to do so in the recent introduction of the High-Speed Train. Adopting a historical perspective is therefore essential for a good understanding of the railway network in Europe, particularly as 70% of the lines currently in service had already been established by 1900. In other words, leaving aside the most recent improvements to railway infrastructure and rolling stock, we are essentially still using a 19th century network. It is therefore relevant to examine the factors that influenced this network’s initial expansion and to study its subsequent transformations through a series of homogeneous data.This research is based on a new GIS dataset that includes all of the railway lines in service at 10-year intervals from 1840 to 2010. These were related to state borders – which changed quite dramatically in the 20th century – for every reference year. The combination of these two layers of information allowed us to monitor national policies and to identify periods of rail construction and closure by area. The specific path followed by each European country was then quantified. This revealed how, historically speaking, the national level has always been the one at which the most important decisions relating to railway networks have been taken, and this remains the case today.

On Construction and Verification of a Safety Model

This paper, conducted through the literature reviews of safety culture models and safety culture dimensions and the application of the management mechanism of the Taiwan Occupational Safety and Health Management System (TOSHMS), proposes a new Omnidirectional Safety Culture Model (OSCM). Four railway companies in Taiwan served as the questionnaire survey subject, and the safety culture of the current railway industry was profoundly investigated. Furthermore, utilizing AMOS analysis software, the thesis verifies the hypotheses by inspecting the structure model with Structural Equation Modeling (SEM).It was indicated in the research that the railway employees’ evaluation of safety culture Significant differences are noted between age and most safety culture dimensions other than “Safety Encouragement and Punishment,” “Performance Measurement,” and “Procurement Management.” In addition, job satisfaction, working environment satisfaction, safety and health policy satisfaction, working efficiency, and possibilities of workplace injuries bear obvious relevance to many safety culture dimensions. The goodness of fit of four safety factors and eighteen safety culture dimensions are confirmed to be acceptable, considering the evaluation result of safety culture structure on all models and synthesizing overall fit indexes. It is ascertained that this model fits better and the result is effective.

Evaluation of Indirect Tensile Strength of Track Ballast Using Weibull Statistics

Iraq is planning to expand and rehabilitate its current railway network, thus demanding huge amounts of proper ballast material. There are three common quarries in Iraq, Sinjaar in the northern sector, Al-Qaim in western desert and Najaf-sea in the middle and southern parts of Iraq. The selection of proper track ballast material is of prime importance in design and construction of railway projects. The single particle-crushing test is a simple indirect tensile test that provides useful data for the selection of the material. Two types of railway ballast materials from (Najaf-sea and Al-Qaim) quarries are commonly used in the construction of railway in Iraq. The single particle-crushing test was performed for various ballast sizes, and the obtained data were analyzed using Weibull analysis. Najaf-sea crushed stones indicate higher tensile strength for all particle sizes compared to corresponding particle sizes of Al-Qaim crushed stone. In addition, an inverse linear relationship had obtained, between tensile strength and particle size with R2 (0.837 and 0.979) for Al-Qaim and Najaf-sea crushed stone, respectively, such relationships are important in evaluating the suitability of the materials in terms of the survival probability

Optimizing Track Infrastructure Availability

Failure to realize the schedule which is primarily reflected in train delays is the direct consequence of insufficient availability of capacities of the current railway infrastructure which are generated by low level of usable quality of the track network in general. The aim of the research presented in this paper is to determine the method of optimal interventions of the rail infrastructure managers and traffic control activities on the reduction of the influence of slow runs and line closures thus ensuring a sufficient number of rail routes for the customers’ needs and consequently higher quality realization of the schedule. The paper gives a concrete presentation of the volume of slow runs and line closures, calculation of reducing the level of railway capacities with a simulation and the result of this condition on the capacity of the concrete railway line and the proposal of a model for organizing an expert group within the traffic control activities for the fastest possible elimination of these negative phenomena. KEY WORDS: liberalization, route leasing, quality deterioration, track availability

<b>Seismic Design of Retaining Wall Considering the Dynamic Response Characteristic</b>

In addition to conventional retaining structures such as retaining walls and bridge abutments, new types of structures such as reinforced-soil retaining walls and reinforced-soil bridge abutments have been introduced for use in railroads. Conventional retaining walls and bridge abutments are classified in the same category as retaining structures under current Railway Technical Research Institute design standards, and the same seismic design procedures are therefore applied. However, their dynamic response characteristics are very different. This study uses a series of shaking table model tests to evaluate the dynamic response characteristics of each structure. The experimental results showed that external forces such as inertial force and earth pressure acting on these structures during shaking were very different. Based on these test results, a new set of seismic design procedures were proposed that use the yield surface of the bearing capacity in order to consider the failure mode combination.

Recommendations for the estimation of the strength of the railway wheel set press fit joint

Although press fit joints are very important in railway engineering, few authors have investigated the strength of press fit joints in terms of their application in railway vehicles. This study analyses the tribological parameters that influence the strength of press fit joints, especially the contact pressure and the static friction coefficient. This research was targeted towards the control of the friction coefficient value to obtain the required strength of a press fit joint in conditions close to the minimum contact pressure that results in less prestressed press fit joints. To estimate press fit joint strength, this study examines the use of minimum and maximum values of the friction coefficient as recommended in the literature considering wide tribological conditions, as well as the experimentally determined friction coefficient values for specific tribological conditions. The study also points out the discrepancy between current railway standards and engineering practice considering the inspection of wheel set press fit joint strength.

Real Options and Incentives in a PPP Railway Project

This master thesis proposes a financial model for the current PPP railway project between Tours and Bordeaux. This work studies the investment opportunity granted to a private concessionaire for this project, considering a semi-stochastic demand. The model uses a standard continuous time real options methodology but also encompasses some concepts from the incentive theory (agency, conflict of interests, effort). Thus, we price the optimal incentives that induce the concessionaire in providing a good quality of service. Finally, some numerical simulations of the project are performed from either real or realistic data, in order to test the model.

Efficient Multisensory Barrier for Obstacle Detection on Railways

On current railway systems, it is becoming ever more necessary to install safety elements to avoid accidents. One of the causes that can provoke serious accidents is the existence of obstacles on the tracks, either fixed or mobile. In this paper, a multisensory system that can inform the monitoring system about the existence of obstacles is proposed. The system for obstacle detection consists of two emitting and receiving barriers, which are placed on opposing sides of the railway, respectively, and use infrared and ultrasonic sensors, thus establishing different optical and acoustic links between them. The interruption of one or several links should produce an alarm. However, even without the existence of objects, degradation of links could occur due to atmospheric attenuation, solar radiation, etc., also producing an activation of the alarm system. Since detection is based on the lack of radiation in the detectors, the use of complementary sensors for the same task is justified. Since the minimum size of an object for which an alarm is required to be generated is 50 × 50 × 50 cm, in some situations, several links are interrupted; however, alarms should not be generated. Typical cases are the flight of leaves or the movement of small animals in the scanned area. To avoid alarm activation in such situations, this paper proposes the combined use of diverse techniques of data fusion, based on fuzzy logic and the Dempster-Shafer theory of evidence, to validate the existence of objects, providing a highly reliable detection system.

Impact of ground subsidence on the Beijing–Tianjin high-speed railway as mapped by radar interferometry

The construction of the Beijing–Tianjin high-speed railway line started in July 2005. The railway has been completed and opened to traffic in August 2008, just before the Beijing Olympic Games. The 113 km railway costing 13.3 billion Yuan (US $1.5 billion) is the country's first high-standard passenger rail. It is also believed to be the pilot project of a massive high-speed rail network in China. The train shuttles passengers between the cities in just half an hour, 45 minutes shorter than the usual travel time. The train is designed to go 200 km/h, but can reach speeds of 350 km/h. The current railway is under pressure, handling 25.55 million passengers each year. The new passenger rail line is expected to handle 32 million passengers from 2008 and 54 million passengers in 2015. Both Tianjin and Beijing have been suffering from ground subsidence due to groundwater extraction. This study focuses on mapping the impact of such subsidence on the Beijing–Tianjin high-speed railway using differential radar interferometry. Both persistent scatterer interferometric synthetic aperture radar (PSInSAR) and differential InSAR (DInSAR) techniques are used to analyse SAR data collected by ENVISAT ASAR and ALOS PALSAR sensors. The results are further analysed in GIS and compared with reported ground survey results.