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This paper considers multi-stage train formation with mixed usage tracks at a marshalling yard without departure yard. A novel integer programming model for scheduling shunting tasks as well as allocating arrival yard tracks and classification bowl tracks is presented. By taking a comprehensive view of the marshalling yard operations, more effective schedules can be found, and a variety of characteristics can be optimised, including shunting work effort, number or cost of tracks, and shunting task start times. Two different objective functions are evaluated: minimising work effort in terms of wagon pull-backs and minimising track costs. A procedure for finding a hot-start solution with few wagon pull-backs is also presented. The proposed model is tested on real data from Sävenäs marshalling yard in Sweden. The results show that the method is able to return an optimal schedule for a planning period of 4 days if the hot-start solution is optimal or the remaining problem is tractable for the heuristics in CPLEX.

Railway capacity allocation in a deregulated market requires planners to solve a mathematically complex optimization problem while simultaneously arbitrating the wants and needs of different stakeholders. This paper analyses timetable quality from the perspective of timetable planners working for the Swedish infrastructure manager Trafikverket. Seven quality aspects are discussed: feasibility, disturbance resistance, competition management, capacity safeguarding, application fulfilment, attractivenessand compatibility with surrounding planning areas. Each aspect is introduced, including references to legal documents, development projects, and research literature. Further, an interview study with eight practitioners gives insight into the current state of practice in Sweden. The practitioners consider feasibility to be both most important and easiest to handle. Capacity safeguarding is considered least important, despite its prevalence in legal documents and envisioned process developments, and is also considered hardest to handle. In general, formal rules and guidelines seem important for emphasising the importance of a quality aspect in the planning process. To better support the planners in their arbitrating role, timetable planning tools based on mathematical optimization models could be implemented. For example, support tools could be used to analyse different solutions, and could unburden the planner from working with feasibility aspects by providing automatic conflict identification and resolution.