The article proposes a simulation-based approach for supporting a threshold analysis aimed at identifying the maximum number of trains to be operated on a line, given the related infrastructural and operational constraints. The method addresses an intermediate case between the theoretical and practical capacity conditions (i.e. simulated capacity). Moreover, the evaluated capacity represents an up- per-bound value and, therefore, it is independent of the involved demand flows which, hence, have been neglected in the provided discussion. In particular, against an initial effort for building the rail micro-simulation model, which requires the modelling of infrastructure layout, signalling system, roll- ing stock and planned timetable, the presented methodology allows infrastructure managers to properly direct the decision-making process by providing information on the effects of any intervention, in ad- vance of its effective implementation. In order to show the feasibility and usefulness of the proposed approach, it has been applied in the case of a real rail network context in the south of Italy.
Railway systems, rail simulation models, railway capacity estimation, threshold analysis, timetabling design process
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