This research report documents the findings from the pre-study project STAPLA-F, conducted by Linköping University and Trafikverket via the research program KAJT. The purpose has been to investigate how strategic facility planning for balancing of maintenance and train traffic could be done, especially regarding switches and crossings (S&C). The project has also investigated the potentials for network simplifications and the removal of (redundant) S&C. Specifically, the station Katrineholm have been used as a case study.

The results show that the economic potential for reducing the S&C maintenance spending can be in the range of 10% for midsize and larger stations, which translates to 70-80 MSEK per year, and that net traffic delays can be reduced by removal of redundant S&C. Furthermore, this is an interesting research problem, which has not yet been addressed in the research literature. Hence, it is recommended to continue with a PhD research project.

Den långsiktiga nationella infrastrukturplaneringen behöver beakta hur investerings- och underhålls-åtgärder planeras både utifrån projektens genomförbarhet och trafikens påverkan, men det saknas idag kvantitativa metoder som kan ge ett sådant stöd i banarbetsplaneringen. Forskningsprojektet SATT (Samplanering av trafikpåverkande åtgärder och trafikflöden, modellstudie) har syftat till att ta fram en metod för att kunna optimera den långsiktiga schemaläggningen av större banarbeten utifrån såväl projektens genomförbarhet som trafikens framkomlighet. Som grund för detta har en översikt av förutsättningarna för den långsiktiga banarbetsplaneringen genomförts tillsammans med en litteraturstudie av vilka angreppssätt som förekommer i forskningslitteraturen. I samarbete med Trafikverket har sedan funktionella krav och behov inventerats och analyserats, med fokus på den ekonomiska planering som görs för ett specifikt produktionsår. Denna delrapport dokumenterar resultaten från litteraturstudien samt krav- och behovsanalysen.

Within the research project SATT, a dynamic traffic assignment method (DTA) has been adapted to simulate railway traffic. This provides an alternative way of railway timetable planning. Unlike traffic flow optimization, DTA simulates the train movements on the smallest time scale (per second) and can solve large scale problems within reasonable amount of time. DTA, however, it does not look for a system optimum, rather it searches for an equilibrium state where no individual train can find an alternative route that further reduces its travel time/generalized cost. This equilibrium status is often referred to as the dynamic user equilibrium. 

This report demonstrates an effort to adapt the transport simulation platform MATSim, as a DTA engine, for railway traffic. The adaptation includes the simulation of railway traffic on single-track, handling of various Temporary Capacity Restrictions (TCR) and different train types. The adapted simulation platform is tested through two small case studies to illustrate the model performance. The result demonstrates the model capability of realistically handling railway traffic and the ability to construct a timetable, given an objective function. Future work should focus on refining the simulation model and test on a large scale national railway network.

In this paper we estimate the impact of line capacity utilisation on the marginal cost of rail infrastructure renewals. Previous studies are mainly concerned with deterioration costs caused by traffic. This paper contributes to the literature, showing that increased line capacity utilisation can – in addition to higher deterioration costs – generate increased costs for carrying out a renewal project and/or more frequent renewals, where the latter can be motivated by efforts to curb expected delays. A top-down econometric approach is used on a Swedish dataset comprising information on renewal costs for track, electric installations, signalling, telecommunication, and other installations such as barriers, fencing and lubrication equipment. The results are relevant for rail infrastructure managers, especially in Europe where directives by the EU stipulate that track access charges are to be based on direct costs in order to contribute to an efficient use of the infrastructure.