In rail freight operation, freight cars need to be separated and reformed into new trains at
hump yards. The classification procedure is complex and hump yards constitute bottlenecks
in the rail freight network, often causing outbound trains to be delayed. One of the problems
is that planning for the allocation of tracks at hump yards is difficult, given that the planner
has limited resources (tracks, shunting engines, etc.) and needs to foresee the future capacity
requirements when planning for the current inbound trains. In this paper, we consider
the problem of allocating classification tracks in a rail freight hump yard for arriving and
departing trains with predetermined arrival and departure times. The core problem can be
formulated as a special list coloring problem. We focus on an extension where individual
cars can temporarily be stored on a special subset of the tracks. An extension where individual
cars can temporarily be stored on a special subset of the tracks is also considered. We
model the problem using mixed integer programming, and also propose several heuristics
that can quickly give feasible track allocations. As a case study, we consider a real-world
problem instance from the Hallsberg Rangerbangård hump yard in Sweden. Planning over
horizons over two to four days, we obtain feasible solutions from both the exact and heuristic
approaches that allow all outgoing trains to leave on time