Maintaining tracks and traffic flow at the same time

•Our model simultaneously schedules trains and track possessions in a railway network.•We minimize traffic disturbance caused by a fixed set of maintenance jobs.•Routes suitable for train rerouting and time windows for possessions are model input.•Start times for possessions and modified, possibly rerouted, trains are model output.•Optionally, cancellations can be allowed as an alternative to rerouting and delays. In an ideal world, all railway tracks would be available to trains at all times. In reality, track sections need to be closed every now and again for track maintenance and upgrades in order to ensure a satisfactory level of safety and comfort. In this paper, we present a MIP model that optimizes a production plan with regard to both trains and preventive maintenance. The planned maintenance activities may not be canceled, but may be moved in time within pre-defined time windows. Trains may be moved in time, redirected to other parts of the geography, or even canceled. The goal for the optimization is to find the best possible traffic flow given a fixed set of planned maintenance activities. In addition to presenting the model, we discuss the current maintenance planning process in Sweden, and exemplify the usefulness of our model in practice by applying it to two typical scenarios.