Shunting of Passenger Train UNits in a Railway Station

In this paper we introduce the problem of shunting passenger train units in a railway station. Shunting occurs whenever train units are temporarily not needed to operate a given timetable. We discuss several aspects of this problem and focus on two subproblems. We propose mathematical models for the problem and both subproblems, one of which is solved with a solution method based on column generation. Furthermore, we introduce a new efficient and speedy solution technique for pricing problems in column generation algorithms. Finally, we present computational results based on real-life instances from Netherlands Railways.