Complex railway systems: capacity and utilisation of interconnected networks

Abstract

Introduction Worldwide the transport sector faces several issues related to the rising of traffic demand such as congestion, energy consumption, noise, pollution, safety, etc. Trying to stem the problem, the European Commission is encouraging a modal shift towards railway, considered as one of the key factors for the development of a more sustainable European transport system. The coveted increase in railway share of transport demand for the next decades and the attempt to open up the rail market (for freight, international and recently also local services) strengthen the attention to capacity usage of the system. This contribution proposes a synthetic methodology for the capacity and utilisation analysis of complex interconnected rail networks; the procedure has a dual scope since it allows both a theoretically robust examination of suburban rail systems and a solid approach to be applied, with few additional and consistent assumptions, for feasibility or strategic analysis of wide networks (by efficiently exploiting the use of Big Data and/or available Open Databases).Method In particular the approach proposes a schematization of typical elements of a rail network (stations and line segments) to be applied in case of lack of more detailed data; in the authors' opinion the strength points of the presented procedure stem from the flexibility of the applied synthetic methods and from the joint analysis of nodes and lines. The article, after building a quasiautomatic model to carry out several analyses by changing the border conditions or assumptions, even presents some general abacuses showing the variability of capacity/utilization of the network's elements in function of basic parameters. Results This has helped in both the presented case studies: one focuses on a detailed analysis of the Naples' suburban node, while the other tries to broaden the horizon by examining the whole European rail network with a more specific zoom on the Belgium area. The first application shows how the procedure can be applied in case of availability of fine-grained data and for metropolitan/regional analysis, allowing a precise detection of possible bottlenecks in the system and the individuation of possible interventions to relieve the high usage rate of these elements. The second application represents an on-going attempt to provide a broad analysis of capacity and related parameters for the entire European railway system. It explores the potentiality of the approach and the possible exploitation of different 'Open and Big Data' sources, but the outcomes underline the necessity to rely on proper and adequate information; the accuracy of the results significantly depend on the design and precision of the input database. Conclusion In conclusion, the proposed methodology aims to evaluate capacity and utilisation rates of rail systems at different geographical scales and according to data availability; the outcomes might provide valuable information to allow efficient exploitation and deployment of railway infrastructure, be...

Railway Capacity Enhancement with Modern Signalling Systems – A Literature Review

“…The type and complexity of the methodology used for capacity assessment relate to quantity and detail of information available and specifics of capacity-related parameters. As a result, different techniques provide slightly different accuracy and precision of the evaluated capacity whose interpretation is consistent with the project evaluation in infrastructure planning, traffic scheduling or other operation-related angles of observation [9,13]. Nevertheless, these techniques often serve as a base for various models that expand the railway capacity, which is why knowing their features is essential.…”

“…Classifications and diversity of individual approaches for capacity assessment have been studied extensively [5,9,10,14,15]. According to [16,17] capacity utilization, i.e., describing the state of the network, should be considered at both the micro and macro levels and defined by the multiple metrics to avoid neglecting uninvolved effects of only one observation level.…”

“…Different authors bring various parameter choices and categories containing parameters of similar characteristics [6][7][8]. The most frequently encountered categorization covers infrastructure, traffic or operational groups of parameters [5,9,10]. Signalling systems are part of the first category described with a number of signalling aspects, train protection, and block lengths.…”

Complex network model for railway timetable stability optimisation

“…Shao and Li designed a complex network model to analyse railway accidents based on the maximal information coefficient [28]. Francesco et al propose a synthetic methodology for the capacity and utilisation analysis of complex interconnected rail networks, allowing both a theoretically robust examination of suburban rail systems [29]. These researchers focused on the analysis and evaluation of the timetable dynamic characteristics related to train timetable stability.…”

Proposal for Streamlining the Railway Infrastructure Capacity on the Specific Track Section in the Context of Establishing an Integrated Transport System

“…Similarly to all operating devices, it is necessary to determine the practical permeability of the railway tracks separately (see equation 2 for even direction and equation 3 for odd direction) [18][19][20] After calculations, it is clear that the practical permeability is for even and odd directions of 180 trains per day [21].…”