IF articles

Summary - Throughout the world, the overwhelm- ing 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 of different func- tionality circulate on the same track. This problem that is currently of concern to numerous railway undertak- ings 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 dif- ferentiating passenger from freight traffic (dedicated ex- ploitation)?” This question could be addressed for a new railway corridor or for an existing corridor. Within the framework of this paper, the economic profitability, ex- pressed by the Net Present Value of the investment, of an existent and of a new railway connection is investigat- ed 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 of exclusively passenger trains on the track; c) “dedicated traffic of freight trains”, i.e. routing of exclusively freight trains on the track. Furthermore the results of the application of the model in an existing railway link of the Greek railway network and specifical- ly in the “Thessaloniki – Alexandroupolis” railway line are presented.