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The aim of this paper is focused on the materials used for the manufacturing of the railway bogie frames. The paper will highlight the allowable and innovative materials after discussing the traditional materials related to the production of this vital rolling stock subsystem. Recently the design optimization is fundamental in all the automotive sectors, also in the railway field. For this reason the rail vehicle manufacturers have been engaged in a process of rolling stock innovation, reduction of cost, weight, material usage and environmental impact during the production and operation of the components. The optimization of the bogie frame has passed from the optimal design of shape, topology, material, the layout of components, the calculation of the strength and load-bearing characteristics of the frame. [ABSTRACT FROM AUTHOR]

This paper presents an in-depth investigation of the engineering aspects related to the design and operation of distributed-power freight trains (F-EMU, freight Electric Multiple Unit), and their potential advantages, by evaluating the various components of this new kind of train and comparing its performance with a traditional freight train. Electric motors, distributed along certain motorised carriages of connected wagons, allow, among others, the power necessary to avoid multiple locomotives, used on traditional lines for the heaviest trains, to be supplied, and access to high-speed lines, which were originally designed and constructed – in Italy for example – for mixed use (i.e. for passengers and freight). Interesting speed levels (140160 km/h) could be achieved, subject to the other requirements of the rolling stock, which are indicated later on in the paper. EMU trains are known to be used for passenger services, as they allow high speeds to be reached, energy to be recuperated during braking and, in general, increases in the performances of the rolling stock to be obtained. Analyses of the operation of freight trains have pointed out that distributed-power trains are able to reach appreciable acceleration values, during traction, because of a better distribution of the adhesive weight. High performances can be achieved, during the braking phase, when electro-dynamic braking, which allows energy to be recovered, is adopted together with a dominant electro-pneumatic braking system: this also prevents the infrastructure operator from having to lengthen the block sections to allow any poorly-braking 700-750 m long traditional trains to transit. The use of such innovative freight trains also satisfies the modern requirements of intermodal transport: electrification of the whole train makes it possible to transport units of refrigerated goods and perishable goods, and to conduct a constant monitoring of the load. After having examined the design and functional requirements of the F-EMU train and a traditional one, a comparison is made of the performances of a distributedpower freight train and a conventional one, on the TurinSavona railway line, through the use of a micro-simulating software package that is able to reproduce the railway operations along the considered stretch and saturate the current passenger timetable with freight trains. From the results, it has emerged that the adoption of distributed-power freight trains leads to a marked reduction of the travel times and an increase in the intermodal transport units (UTI) that can be transported over the reference time frame, especially when considering the use of 750 m long trains. [ABSTRACT FROM AUTHOR]

In recent years, there has been a continuous and rapid increase in the number of urban mass railway transportation systems put in revenue service worldwide. As new metro, tramway, and monorail systems are being put into circulation, they are supplemented by innovations in rolling stock, infrastructure, and operational equipment / procedures. As a result, they provide more efficient public transport to more people. Consequently, the need arises for frequent updates of relevant data. This paper initially attempts to systematically record the tramways, the metros, and the monorails currently in revenue service and under construction worldwide. It continues with a statistical analysis of their basic characteristics in an effort to showcase and compare trends. For meaningful information to be acquired, data acquisition is based on clear definitions of such systems. In this aspect, the paper provides clear criteria for the distinction of urban mass railway systems. The findings were recorded at the end of 2019. [ABSTRACT FROM AUTHOR]

The paper shows some initial results of Assets4Rail, an EU founded project that aims to contribute to the modal shift towards rail by exploring, adapting and testing the most advanced technologies for railway asset monitoring and maintenance, in order to ensure a proactive and cost-effective maintenance and intervention systems on the assets (both rail infrastructure and rolling stock with regard to defects affecting the track). The core of the project is to develop an integrated system to gather and analyse information, collected by specific on-site sensors, as well as train mounted automated monitoring systems, for detecting defects that have non-negligible impacts on infrastructure. The first step of the project, as described in the present paper, is the state-of-the-art review of previous EU/national funded projects, industry solutions and research papers, to identify drivers, benchmarks and emerging solutions and assess potentially applicable technologies and solutions in the fields of sensor system for track geometry monitoring. In this context, the paper defines the requirements, classified into functional, operational, performances and safety for further developments and testing of an on-board sensor system able to measure the transversal position of the wheel in relation to the rail in order to support track geometry measurements. [ABSTRACT FROM AUTHOR]

In railway operations, data provided by wayside measuring systems could be useful for many reasons as ensuring safety and facilitating maintenance of the tracks. For example, measuring devices of wheel-rail contact forces allow the monitoring of any kind of rolling stock under specific operating conditions, like curves at low speed or twisted tracks, which are always present in stations, depots and marshalling yards. For that reason, in this paper we present the evaluation of the robustness of the SMCT wayside measurement system. The system is based on a particular strain gauges configuration on the rail foot, able to isolate the effects of the lateral force from those of the vertical one and record the lateral force using a proportional coefficient between that force and strains. The system has been validated with several field tests directly on a railway line in service: about 4000 transit and different types of trains, up to 110 km/h. The aim of the work is to build a fitting regression model able to predict the value of the ratio between the lateral force and strains in order to test the robustness of the measurement method and its operating range, modifying parameters that experimentally could not have been changed. [ABSTRACT FROM AUTHOR]

In this paper, a specific procedure is adopted for making a distinction between conventional-speed rail, high-speed rail, and very high-speed rail. The criteria adopted correspond to the needs of the actors that manage the 3 constituents of a railway system and namely the infrastructure managers (track) and the operators (rolling stock, railway services). Based on this distinction, research was focused on: a) identifying all countries, which possess at least one track of very high-speed b) making a record, for all the identified countries, of the total length of tracks that are characterized as very highspeed tracks c) analyzing the evolution of the construction of very highspeed tracks over the years d) making a record of very high-speed trains that were set in circulation over the last 5 years Making a record per country, of the longest direct route, which, based on the adopted definition, provides services of very high-speed. [ABSTRACT FROM AUTHOR]

This paper describes an optimization framework for rolling stock rostering and maintenance scheduling at a busy workshop. A new mixed-integer linear-programming formulation is provided for the maintenance scheduling problem faced by Trenitalia (train operating company) managers, with input data taken from the rolling stock rostering plan. The computational results are carried out on a Trenitalia's maintenance site located in Naples. The solutions computed via a commercial MILP solver are compared with practical solutions. A relevant cost reduction is possible by using the proposed framework, involving both rostering and maintenance scheduling. We also show how the proposed method can be used as an effective tool to absorb real-time timetable perturbations while respecting the agreed level of service. [ABSTRACT FROM AUTHOR]