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Proceedings of the Institution of Mechanical Engineers Part F: Journal of Rail and Rapid Transit [6 followers] Follow
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ISSN (Print) 0954-4097 - ISSN (Online) 2041-3017
Published by Sage Publications

[710 journals] [SJR: 0.449] [H-I: 21]

Special Issue on RRUKA research
- Authors: Dennis, C; Iwnicki, S.
  Pages: 593 - 593
  PubDate: 2013-11-07T03:37:19-08:00
  DOI: 10.1177/0954409713510814|hwp:resource-id:sppif;227/6/593
  Issue No: Vol. 227, No. 6 (2013)
Optimisation of wheelset maintenance using whole-system cost modelling
- Authors: Bevan, A; Molyneux-Berry, P, Mills, S, Rhodes, A, Ling, D.
  Pages: 594 - 608
  Abstract: The maintenance and renewal activities of wheelsets account for a large proportion of the whole-life costs for railway rolling stock. These activities are influenced by a large number of factors including depot constraints, wheel surface damage, fleet availability and vehicle design. If these factors are not managed efficiently it can have significant implications on a vehicle’s service provision, track damage, environmental and whole-life costs. Therefore, the development of an effective wheelset management tool will support the optimisation of maintenance and renewal regimes, thereby increasing wheelset life and reducing costs. Further development of the Vehicle Track Interaction Strategic Model has enhanced the rolling stock modelling capabilities of the tool through the development of the Wheelset Management Model (WMM). This model aims to assist in the strategic planning of wheelset maintenance and renewal activities and thereby allowing users to examine the benefits and cost impact of a range of different scenarios to optimise wheelset management strategies. This paper describes the capabilities of the WMM and illustrates how the model can be used to optimise a fleet’s maintenance strategy through the application of a realistic industry case study. The implications of different wheelset maintenance regimes on wheelset life and costs were examined. Finally, the paper presents how the tools can be used to investigate whole-system costs and demonstrate the impact of wheelset maintenance on track costs.
  PubDate: 2013-11-07T03:37:20-08:00
  DOI: 10.1177/0954409713484712|hwp:master-id:sppif;0954409713484712
  Issue No: Vol. 227, No. 6 (2013)
Aerodynamic pressures around high-speed trains: the transition from unconfined to enclosed spaces
- Authors: Gilbert, T; Baker, C, Quinn, A.
  Pages: 609 - 622
  Abstract: The theory and practice of train-induced aerodynamic pressure loads on surfaces near to the tracks is compromised by an incomplete understanding of trains operating in short tunnels, partially enclosed spaces, and next to simple structures such as vertical walls. Unique pressure-loading patterns occur in each case. This work has been carried out to obtain a fundamental understanding of how these loading patterns transition from one to the other as the infrastructure becomes more confined. It also considers the impact of the results on two separate European codes of practice applying to tunnels and other structures. A parametric moving-model study was undertaken, transitioning from the open air to single and double vertical walls, partially enclosed spaces, short single-track tunnels and a longer tunnel. The train model was based on a German ICE2, and was fired at 32 m/s past the structures. Multiple surface pressure tappings and in-flow probes were used, providing the opportunity to assess the three-dimensional nature of the pressure and velocity fields. The experiments successfully mapped the transition between the three loading patterns and isolated the geometric changes. Further loading patterns were discovered relating to the length of the train, the length of the tunnel and the distance from the tunnel entrance. The three-dimensional nature of the pressure was related to the length of the tunnel and the distance from the tunnel entrance. Issues surrounding the lack of provision in codes of practice for short tunnels were discussed.
  PubDate: 2013-11-07T03:37:20-08:00
  DOI: 10.1177/0954409713494947|hwp:master-id:sppif;0954409713494947
  Issue No: Vol. 227, No. 6 (2013)
Real time detection of low adhesion in the wheel/rail contact
- Authors: Hubbard, P; Ward, C, Dixon, R, Goodall, R.
  Pages: 623 - 634
  Abstract: Condition monitoring of railway vehicles has been highlighted by the railway industry as a key enabling technology for future system development. The primary uses for this could be the improvement of maintenance procedures and/or the identification of high-risk vehicle running conditions. Advanced processing of signals means these tasks could be accomplished without the use of cost prohibitive sensors. This paper presents a system for the on-board detection of low-adhesion conditions during the normal operation of a railway vehicle. Two different processing methods are introduced. The first method is a model-based approach that uses a Kalman–Bucy filter to estimate creep forces, with subsequent post processing for interpretation into adhesion levels. The second non model-based method targets the assessment of relationships between vehicle dynamic responses to observe any behavioural differences as a result of an adhesion-level change. Both methods are evaluated in specific case studies using a British Rail (BR) Mark 3 coach, inclusive of a BR BT-10 bogie, and a generic modern passenger vehicle based on a contemporary bogie design. These vehicles were chosen as typical application opportunities within the UK. The results are validated with data generated by the multi-body simulation software VAMPIRE® for realistic data inputs, representing a key scientific achievement.
  PubDate: 2013-11-07T03:37:20-08:00
  DOI: 10.1177/0954409713503634|hwp:master-id:sppif;0954409713503634
  Issue No: Vol. 227, No. 6 (2013)
The aerodynamics of freight: approaches to save fuel by optimising the utilisation of container trains
- Authors: Beagles, A. E; Fletcher, D. I.
  Pages: 635 - 643
  Abstract: Aerodynamic drag is approximately proportional to speed squared so the drag of slower moving freight trains has received less attention than that of higher-speed passenger trains. Key results of wind tunnel tests of European container trains were published in 1989 and are the basis for most assessments of drag of European container trains (American container trains usually have far higher drag due to double-stacking containers or transporting complete semi-trailers and were studied in research programmes at a similar time). The research reported here concerns a reappraisal of the European results and of more recent results obtained from the application of computational fluid dynamics modelling and the results of real-world and wind tunnel testing of the aerodynamics of container wagons. The paper presents empirical equations that can be used to predict the energy savings associated with different container loading scenarios within a fixed length train and the energy required for carrying aerodynamic features such as baffles or fairings. Illustrative examples are provided using data measured during freight operations. The effect on drag of side winds and their speed distributions are included as are representative vehicle speed profiles. Most previous authors have ignored both side winds and end effects; it is shown that the effects of these are opposite but of similar magnitudes so the results of these authors remain valid.
  PubDate: 2013-11-07T03:37:20-08:00
  DOI: 10.1177/0954409713488101|hwp:master-id:sppif;0954409713488101
  Issue No: Vol. 227, No. 6 (2013)
Modelling railway bridge asset management
- Authors: Le, B; Andrews, J.
  Pages: 644 - 656
  Abstract: Railway bridges form one of the major railway asset groups with more than 35,000 bridges on the UK rail network. Additionally, the bridge structures are old with more than 50% of the population constructed over 100 years ago. Due to the unique nature of each bridge and their varied means of construction, the decision as to what type of maintenance actions should be performed and when to perform them is a complex problem. Models can be formulated to predict the future condition of assets along with the effect that interventions such as servicing, repair and element replacement will produce. This can be used to support this decision making process. This paper demonstrates a Markov modelling approach to predict the condition of individual bridge elements. For each bridge element the degradation process is determined by examining the maintenance records and analysing the times that each element takes to deteriorate to the point where maintenance of a certain severity classification is required. By combining the elemental models, an overall bridge model is formed which can be used to investigate different maintenance strategies. The model is capable of accounting for a bridge’s current condition, material, route criticality, structural arrangement and environment. The maintenance, opportunistic maintenance and renewal strategy can also be varied in the model along with the service frequency, inspection frequency and repair delay time. Using the model the whole life costs can be predicted for any of the selected maintenance strategies.
  PubDate: 2013-11-07T03:37:20-08:00
  DOI: 10.1177/0954409713490924|hwp:master-id:sppif;0954409713490924
  Issue No: Vol. 227, No. 6 (2013)
Influence of unsupported sleepers on the dynamic response of a heavy haul railway embankment
- Authors: Shi, J; Chan, A. H, Burrow, M. P.
  Pages: 657 - 667
  Abstract: It is not uncommon for conventional ballasted railway track systems to have unsupported sleepers due the uneven settlement of the ballast or subgrade. In order to investigate the possible implications of unsupported sleepers, this paper describes the development of a dynamic finite element model which includes wheel/rail friction. The developed model was used to investigate the behavior of a section of existing track on the ballasted Shuohuang heavy haul railway line in China. The investigation showed that the maximum displacement of the rails and sleepers increases significantly with the number of consecutive unsupported sleepers. Furthermore, the magnitude of the displacement between an unsupported sleeper and the ballast is likely to greatly exacerbate ballast/sleeper attrition and reduce the fatigue life of the hanging sleeper. An increase in the number of unsupported sleepers amplifies these effects. In addition, it was found that the sleepers adjacent to unsupported ones carry an additional load resulting potentially in their increased wear and additional damage to the substructure. To better understand the wider implications of the presence of unsupported sleepers on track performance, the stability, safety (in terms of derailment) and potential for rail and substructure damage were computed as a function of the number of unsupported sleepers (one to four) and compared with specifications. The results showed that the number of unsupported sleepers has a significant adverse impact on all four measures. However, while the effects on stability, safety and rail damage were within the limits suggested in specifications, even when four sleepers were modeled, the potential for substructure failure within a typical design life of the railway system was identified.
  PubDate: 2013-11-07T03:37:20-08:00
  DOI: 10.1177/0954409713495016|hwp:master-id:sppif;0954409713495016
  Issue No: Vol. 227, No. 6 (2013)
Responding to the Environmental Noise Directive by demonstrating the benefits of rail grinding on the Great Britain's* railway network
- Authors: Craven, N; Bewes, O. G, Fenech, B. A, Jones, R.
  Pages: 668 - 676
  Abstract: This paper investigates a significant reduction in environmental noise attributable to changes in the Network Rail grinding strategy employed within GB. It also considers how these findings could inform noise mapping and action plans required by the Environmental Noise Directive (END). Acoustic track quality (ATQ) is a measure of the surface roughness of the running rails and is proportional to wayside rolling noise levels during the passage of a train. Levels of ATQ have been determined for approximately 1100 km of track on GB’s East and West Coast mainlines from wayside noise measurements made during the pass-by of Network Rail’s New Measurement Train and data collected by an under-carriage microphone system fitted to this train. The results show a substantial apparent reduction in rail surface roughness and associated wayside noise levels since a similar study was undertaken in 2004. While these findings require further verification they are supported by initial direct rail head roughness level measurements which also show low levels of roughness. The results of the study show how a maintenance rail grinding strategy can potentially reduce wayside noise levels across large parts of a railway network. While the measure of track quality used to evaluate the benefits of a maintenance rail grinding strategy is specific to GB’s method for calculating railway noise, the results also provide insight into the potential benefits of maintenance rail grinding on networks outside of GB. In addition the results demonstrate the importance of including a track quality parameter, such as ATQ, in any prediction methodologies for rail noise used in noise mapping exercises, such as those being undertaken as part of the END.
  PubDate: 2013-11-07T03:37:20-08:00
  DOI: 10.1177/0954409713494948|hwp:master-id:sppif;0954409713494948
  Issue No: Vol. 227, No. 6 (2013)
Developing system models to help Great Britain's railways embrace innovative technologies with confidence
- Authors: Bouch, C. J; Roberts, C.
  Pages: 677 - 684
  Abstract: Railways are under pressure to become more efficient and cut their costs; innovation has a part to play in achieving these goals. The railway is, however, a complex and closely coupled system, making it difficult in the early stages of development, to be clear what the system-wide impact of innovation will be. The research covered in this paper stems from the idea that computer-based models of existing systems can help overcome this problem, by providing a baseline framework against which the impact of innovation can be identified. The paper describes development of a repeatable modelling methodology, which elicits objective system data from Railway Group Standards and integrates it using CORE®, a powerful system modelling tool, to create system models. The ability of such models to help identify impacts is verified, using as an example the introduction of RailBAM (a new technology that acoustically monitors the health of rolling stock axle bearings) into the existing hot axle bearing detection system.
  PubDate: 2013-11-07T03:37:20-08:00
  DOI: 10.1177/0954409713500485|hwp:master-id:sppif;0954409713500485
  Issue No: Vol. 227, No. 6 (2013)
Challenging established rules for train control through a fault tolerance approach: applications at a classic railway junction
- Authors: Liu, R; Whiteing, A, Koh, A.
  Pages: 685 - 692
  Abstract: Current rules of railway operations employed in the UK can be regarded as conservative. While the safety of passengers is a clearly an overriding paramount consideration, such rules may represent a drawback in that they reduce capacity. At present, with high and growing demand there is a clear need to increase railway capacity. While construction of new lines or significant augmentation of existing ones offer ways of providing increased capacity, there is a long gestation period and it is extremely expensive at a time of tight governmental budgetary constraints. A viable alternative is to investigate methods of increasing the productivity of the current infrastructure by understanding how the established rules of railway operation can be challenged without compromising the safety of the passengers. To accomplish this stated goal, a fault-tolerance-based approach to train controls at nodes (junctions and stations) is proposed. This paper introduces the concept of fault tolerance in the context of train operations at a classic railway junction, presents a dynamic, mesoscopic simulation model developed to represent the new control rules and discusses initial results from the application of this approach on capacity gains.
  PubDate: 2013-11-07T03:37:20-08:00
  DOI: 10.1177/0954409713496988|hwp:master-id:sppif;0954409713496988
  Issue No: Vol. 227, No. 6 (2013)
Applications, value and barriers of common data frameworks in the rail industry of Great Britain
- Authors: Golightly, D; Easton, J. M, Roberts, C, Sharples, S.
  Pages: 693 - 703
  Abstract: In the rail industry, the exchange of data across system and organisational boundaries is an essential step in the delivery of advances such as intelligent infrastructure, end-to-end ticketing, improved passenger information, real-time capacity management and greater interoperability between stakeholders. The industry, however, faces a serious challenge in the form of siloed, legacy ICT systems based around different technologies and data formats. One solution to this problem can be found in the implementation of open data interfaces that use a conceptual representation of the railway network to facilitate the exchange of information while preserving its underlying meaning. The work reported in this paper used two engagement exercises involving industry stakeholders to, first, generate a set of applications for wider information sharing in the rail industry of Great Britain; second, compile a list of the benefits of such an approach to the rail industry; and, third, identify the most significant barriers to implementation. The paper should therefore be valuable for anyone in industry or in academia working on projects that depend on the exchange of data between systems and stakeholders to support rail operations and strategy.
  PubDate: 2013-11-07T03:37:20-08:00
  DOI: 10.1177/0954409713499148|hwp:master-id:sppif;0954409713499148
  Issue No: Vol. 227, No. 6 (2013)
Change and safety: decision-making from data
- Authors: Bearfield, G; Holloway, A, Marsh, W.
  Pages: 704 - 714
  Abstract: The UK rail industry collects and analyses incident data to assess the risks experienced by passengers, the railway workforce and members of the public. The current analysis mainly compares current and historic incident rates and, for each type of incident, looks at the railway as a whole. However, changes to reduce risk are often made locally, at least at first, so a modelling approach is needed that is able to analyse local risk. In this paper we present a form of model that is able to make local risk estimates from incident data, using a case study – boarding and alighting incidents at stations. Using a Bayesian network (BN), we analyse the incident data with expert judgements about causal factors. The BN cannot be directly leant from data because the dataset contains no entries for the overwhelming majority of cases where the railway is used without incident. Instead, the incident data is analysed in the context of a model of the use of the railway, so that the prevalence of the causal factors in normal use can be compared with that in the incident data. The usage model is derived from multiple data sets; the use of a BN allows this to be done with approximations. Finally, we show how the model allows local risk to be estimated and consider the wider applicability of the techniques described.
  PubDate: 2013-11-07T03:37:20-08:00
  DOI: 10.1177/0954409713498381|hwp:master-id:sppif;0954409713498381
  Issue No: Vol. 227, No. 6 (2013)
Reducing the risk of suicide or trespass on railways: developing better interventions through understanding behaviours of people
- Authors: Ryan; B.
  Pages: 715 - 723
  Abstract: Suicide and trespass are major problems for railway operators in Great Britain, leading to around 250–300 fatalities per year, as well as associated major disruption to the rail network. The European Union project RESTRAIL, composed of a broad consortium of experts and rail operators from across Europe, is attempting to tackle these important issues. This paper presents an overview of two parts of the project that are being led by research in the UK; understanding observable behaviours prior to suicide and trespass incidents and the development of a methodology for the evaluation of preventative measures against suicide and trespass. Solving the problems of railway suicide and trespass is difficult. Opportunities for interventions, based on a better understanding of the behaviours displayed by people leading up to these incidents, are discussed.
  PubDate: 2013-11-07T03:37:20-08:00
  DOI: 10.1177/0954409713497200|hwp:master-id:sppif;0954409713497200
  Issue No: Vol. 227, No. 6 (2013)
Extending geographically weighted regression from points to flows: a rail-based case study
- Authors: Blainey, S. P; Preston, J. M.
  Pages: 724 - 734
  Abstract: At present in the UK an elasticity-based approach is used to forecast changes in rail passenger demand resulting from changes in both the rail service offer and external conditions, with uplift factors calculated based on the proportional change in the level of explanatory variables over time. Changes in these explanatory variables may have differing effects on rail demand in different areas. This is currently controlled for via a limited segmentation of the market with different elasticities estimated for each segment, which inevitably limits the complexity of the variations which can be captured. This paper describes the use of geographically weighted regression (GWR) to enhance the modelling of such spatial variation. First, conventional cross-sectional demand models were calibrated covering major rail flows across the Great Britain. These models were then recalibrated using GWR to allow assessment of spatial variations in rail demand elasticities. Previous applications of GWR have almost exclusively focused on spatial data which have a single point location. This is not the case for rail flows, and this paper compares the results given by several different methods for defining point locations for flows. It also assesses different methods for approximating GWR results to simplify their application in real-life forecasting situations. The results show that the use of GWR can give a significant improvement in the fit of flow-based rail demand models, and that it is possible to spatially segment the UK passenger rail market based on the results from these models. In order to integrate such segmentations with the standard UK rail demand forecasting methodology it would, however, be necessary to extend the GWR methodology further to allow the calibration of GWR models on panel data.
  PubDate: 2013-11-07T03:37:20-08:00
  DOI: 10.1177/0954409713496987|hwp:master-id:sppif;0954409713496987
  Issue No: Vol. 227, No. 6 (2013)