How the Swiss Federal Railways are going to decide on track types in future (slab track v. ballasted track)

Die Schweizerische Bundesbahn SBB (Infrastruktur) haben basierend auf einer umfassenden Studie unter Einbezug der internationalen Erfahrungen ihre Strategie für den Einsatz der Festen Fahrbahn auf freier Strecke überdacht und neu festgelegt. Der Beitrag zeigt Grundlagen, Parameter und Systematik der Einscheidungsfindung für Feste Fahrbahn oder Schotteroberbau auf, wobei nach einem so genannten Schalenmodell die Untersuchung von der alleinigen Betrachtung des Oberbaues schrittweise bis zum Gesamt-System Bahn vorangetrieben wird. The Infrastructure division of the Swiss Federal Railways (SBB / CFF / FFS) has recently revised and modified its strategy for the use of slab track on open sections of railway lines. This review was based in a far-reaching survey, which also took in experiences in other countries. The authors present the basic principles, the parameters and the systematic structure of the process for deciding between slab track and ballasted track. The underlaying model consists of concentric shells and starts by contemplating the permanent way in isolation, before advancing, a layer at a time, until it considers the railway as a complete system. The outcome of the investigations carried out by the Swiss Federal Railways is that today's familiar forms of slab track are too inflexible for the conditions prevailing in Switzerland for open-air use on top of earth structures, that there are high latent risks, and that the existing systems are too expensive (measured in terms of life-cycle costs). The life-cycle labour time for laying and maintaining slab track has been found to be significantly higher. Thes conclusions do not, however, rule out slab track altogether. On a case-by-case basis, the technology may be considered for new or upgraded lines where improving travel times over selected sections could be in the interests or an overriding timetable concept. Weiterführende Informationen: http://www.zhaw.ch/~steo/FF-SchO_ETR.pd