Selezione dello scenario ottimale di utilizzo per un corridoio ferroviario interurbano con l'ausilio di modelli matematici.

Throughout the world, the overwhelming majority of railway corridors concern mixed train operation. Express and local passenger trains along with freight trains are routed on the same track. On the one hand, this practice seems to achieve scale economies, as most trains use the same railway infrastructure; on the other hand, it creates problems in exploitation and maintenance of the network, as trains o f different functionality circulate on the same track. This problem that is currently of concern to numerous railway undertakings it can be expressed by the following question: ‘‘What is more economically efficient for a railway company? Simultaneously routing passenger and freight trains (mixed exploitation) on a single railway corridor, or differentiating passenger from freight traffic (dedicated exploitation)?" This question could be addressed for a new railway corridor or for an existing corridor. Within the framework o f this paper, the economic profitability, expressed by the Net Present Value of the investment, of an existent and of a new railway connection is investigated by the use of a mathematical model and considering various values of transport volume demand. For both cases, a single, standard gauge track is considered. In regard to traffic composition, three cases are examined: a)“mixed train traffic"; b)“dedicated traffic of passenger trains", i.e. routing o f exclusively passenger trains on the track; c) “dedicated traffic of freight trains", i.e. routing o f exclusively freight trains on the track. Furthermore the results of the application of the model in an existing railway link o f the Greek railway network and specifically in the “Thessaloniki - Alexandroupolis" railway line are presented. [ABSTRACT FROM AUTHOR]