Train turn restrictions and line plan performance

In this paper we study the impact of the `turn conditions' in end stations on the performance of a line plan. If trains have to turn on their platform in an end station, the yoccupy the platform for several minutes. A more preferred option, from a timetabling point of view, would be that a train disappears from the platform in its end station after dwelling and only appears again when departing for a subsequent trip.

In this case, the train will not interfere with other trains that dwell on the platform during the time between these events. However, this option is only possible if the train can stay in a exible and large enough shunt. Starting from a given line plan, we compare two timetables, one where trains have to turn on their platform and one where trains can turn in a shunt.

We evaluate the impact on the performance of the line plan by its feasibility for timetabling,the minimum overall buffer time between trains, the sum of the buffer times and the buffer times in individual stations. A case study on the DSB S-tog in Copenhagen (Denmark) is performed.