Abstract
In order to assess the actual ability of planned infrastructure investments to satisfy the required demand of service, railway engineers also need to plan the new offer of train services. In turn, this requires a full re-planning of the line system and of the frequency of each line. In cooperation with the Sales and Network Management department of the Italian infrastructure manager, we developed a model to determine an optimal set of lines and the corresponding train frequencies. The model has been successfully applied to evaluate alternative infrastructure enhancements in the metropolitan rail network of Rome. A set of computational experiments has been carried out, providing interesting insights on the effects of different infrastructural intervention policies.