Availability of paths for fast freight services on an Italian high speed railway.

The paper presents a study concerning the feasibility of fast freight services on high speed lines, which have been so far utilised for passenger traffic only, though designed also for heavy freight trains. The influence of possible significant speed improvements of freight rolling stock is taken into account, considering a part of the Italian high speed-high capacity network as a case study, the Milano-Bologna line. A timetable-based approach is followed, making use of a dedicated analysis methodology. The analysis relies on a routing-scheduling algorithm (embedded in a railway capacity analysis tool) used for identifying available time slots for inserting additional freight paths. Overtakings are scheduled where needed, without altering the passenger timetable. 16 scenarios are analysed, they are different for which regards the top speed of the freight trains and the locations where the latter can enter/exit the analysed network. The possibility of scheduling overtakings “whilst in motion” is examined as well. The scenarios are analysed considering as indicators the daily number of available freight paths, their distribution along the day and their quality, i.e. the amount of extra dwell time in intermediate stations due to possible overtakings. The robustness of the extra freight paths is then assessed, in order to check their actual feasibility in case of common perturbations of the passenger traffic. Results obtained are then discussed, highlighting how the heterogeneity of the traffic significantly reduces the residual capacity.