Change search
ReferencesLink to record
Permanent link

Direct link
Influences of station length and inter-station distance on delays and delay propagation on single-track lines with regional rail traffic
KTH, School of Architecture and the Built Environment (ABE), Transport and Economics (closed 20110301), Traffic and Logistics (closed 20110301). KTH, School of Engineering Sciences (SCI), Centres, The KTH Railway Group. (Tågtrafikgruppen)
2006 (English)In: Computers in Railways X: Computer System Design and Operation in the Railway and Other Transit Systems / [ed] Allan, J; Brebbia, CA; Rumsey, AF; Sciutto, G; Sone, S; Goodman, CJ, Southampton: WIT Press , 2006, 511-520 p.Conference paper (Refereed)
Abstract [en]

Train services on single-track lines suffer from time losses due to crossings, imposed by the bidirectional traffic. The time losses, in this paper denoted crossing time, are caused by constraints in the infrastructure and delay propagation, which give a stochastic contribution that varies from one crossing situation to another.

Two examples of infrastructure improvements that decrease the crossing time are examined: partial double-track at the location of timetabled crossing and decreased inter-station distances. A mathematical model is used to evaluate these improvements.

Partial double-tracks seem to be very efficient when traffic intensity and delay variances are moderate. Shortened inter-station distances give less effect but are less sensitive to delay variance and give valuable additional line capacity.

The used model assumes independence between crossing trains, which imposes a moderate capacity utilisation. In more congested situations simulation methods are needed to make more complex crossing patterns possible.

Place, publisher, year, edition, pages
Southampton: WIT Press , 2006. 511-520 p.
Keyword [en]
single-track, delay propagation, partial double-track, inter-station distance
National Category
Reliability and Maintenance Civil Engineering
Research subject
Järnvägsgruppen - Kapacitet
URN: urn:nbn:se:kth:diva-12726DOI: 10.2495/CR060511ISI: 000240944200051ScopusID: 2-s2.0-36148979378ISBN: 1-84564-177-9OAI: diva2:318288
10th International Conference on Computer System Design and Operation in the Railway and Other Transit Systems. Prague, CZECH REPUBLIC. JUL 10-12, 2006
Framtida infrastruktur och kvalitet i tågföring
QC 20100622 QC 20111006Available from: 2010-05-07 Created: 2010-05-07 Last updated: 2012-02-28Bibliographically approved
In thesis
1. Railway operation analysis: Evaluation of quality, infrastructure and timetable on single and double-track lines with analytical models and simulation
Open this publication in new window or tab >>Railway operation analysis: Evaluation of quality, infrastructure and timetable on single and double-track lines with analytical models and simulation
2010 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

This thesis shows the advantages of simple models for analysis of railway operation. It presents two tools for infrastructure and timetable planning. It shows how the infrastructure can be analysed through fictive line designs, how the timetable can be treated as a variable and how delays can be used as performance measures. The thesis also gives examples of analyses of complex traffic situations through simulation experiments.

Infrastructure configuration, timetable design and delays play important roles in the competitiveness of railway transportation. This is especially true on single-track lines where the run times and other timetable related parameters are severely restricted by crossings (train meetings). The first half of this thesis focuses on the crossing time, i.e. the time loss that occurs in crossing situations. A simplified analytical model, SAMFOST, has been developed to calculate the crossing time as a function of infrastructure configuration, vehicle properties, timetable and delays for two crossing trains. Three measures of timetable flexibility are proposed and they can be used to evaluate how infrastructure configuration, vehicle properties, punctuality etc affect possibilities to alter the timetable.

Double-track lines operated with mixed traffic show properties similar to those of single-tracks. In this case overtakings imply scheduled delays as well as risk of delay propagation. Two different methods are applied for analysis of double-tracks: a combinatorial, mathematical model (TVEM) and simulation experiments.

TVEM, Timetable Variant Evaluation Model, is a generic model that systematically generates and evaluates timetable variants. This method is especially useful for mixed traffic operation where the impact of the timetable is considerable. TVEM may also be used for evaluation of different infrastructure designs. Analyses performed in TVEM show that the impact on capacity from the infrastructure increases with speed differences and frequency of service for the passenger trains, whereas the impact of the timetable is strongest when the speed differences are low and/or the frequency of passenger services is low.

Simulation experiments were performed to take delays and perturbations into account. A simulation model was set up in the micro simulation tool RailSys and calibrated against real operational data. The calibrated model was used for multi-factor analysis through experiments where infrastructure, timetable and perturbation factors were varied according to an experimental design and evaluated through response surface methods. The additional delay was used as response variable. Timetable factors, such as frequency of high-speed services and freight train speed, turned out to be of great importance for the additional delay, whereas some of the perturbation factors, i.e. entry delays, only showed a minor impact. The infrastructure factor, distance between overtaking stations, showed complex relationships with several interactions, principally with timetable factors.

Place, publisher, year, edition, pages
Stockholm: KTH, 2010. 53 p.
Trita-TEC-PHD, ISSN 1653-4468 ; 10-001
Railway operation, Railway capacity, Single-track, Double-track, Partial double-track, Inter-station distance, Delay, Delay propagation, Crossing, Overtaking, Timetable flexibility, Simulation, Experimental design
National Category
Civil Engineering
urn:nbn:se:kth:diva-12727 (URN)978-91-85539-50-5 (ISBN)
Public defence
2010-05-28, E1, Lindstedtsvägen 3, KTH, Stockholm, 10:00 (English)
Framtida infrastruktur och kvalitet i tågföring
QC20100622Available from: 2010-05-12 Created: 2010-05-07 Last updated: 2010-06-22Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full textScopus

Search in DiVA

By author/editor
Lindfeldt, Olov
By organisation
Traffic and Logistics (closed 20110301)The KTH Railway Group
Reliability and MaintenanceCivil Engineering

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 115 hits
ReferencesLink to record
Permanent link

Direct link