Assessment of the sustainability of the traditional and innovative rail track systems in a long-term perspective

In the last decades special attention is being paid to ballast-less track systems, for their more suitability to be applied in high-speed lines with respect to the ballasted systems. Considering this fact, the present study aims at evaluating the technical, economic and environmental features of competing track solutions in a long-term perspective in order to ascertain their sustainability. Traditional track, who main components are: ballast, sleepers, fastenings, baseplates, rails; and innovative track, usually constituted by pre-stressed concrete slab, fastenings, pad and rails, are put in comparison. Regarding the technical aspects, the advantages and disadvantages of each solution are analyzed, considering the traffic and the speed of the railway line. For the economic aspects, the costs of construction, maintenance and renewal are considered. The environmental aspects account for the impacts produced by the construction/maintenance/renewal activities, and they are estimated in terms of greenhouse emissions (CO2e) and related cost. A LCCA-based method for assessing the best strategy for the design and management of a railway track over time (maintenance and renewal), considering a long-term perspective, is also set up. Results shows that solutions reasonably priced in the short period could become less sustainable in a long period.