Railway capacity management and planning

This research presents a novel model of the railway master scheduling problem, applies it to a theoretical study of railway line capacity under representative conditions, and offers a method for applying this model to practical railway scheduling problems. Contemporary market demands for different classes of rail transportation service are not adequately served because of the inability to assess the cost to the network of disparate services, as well as the inability to determine optimal scheduling. Disputes over cost and scheduling also arise between entities managing disparate services that must share common infrastructure.; This new model represents railway schedules as binary multicommodity flows on discrete time scales, mapped on a hypergraph. The objective function calculates network value as a linear combination of viable train paths, en route delay, and destination tardiness. Studies are presented that estimate the cost of imposing a non-conforming, high speed train on an existing congested, homogeneous railway network flow. The analysis is provided for two formats of single track railway and for one common format of double track railway. A significant benefit is demonstrated when track networks are configured to allow complex train interactions that are not limited to pairwise meets and passes. In addition, a novel claim is made that under some conditions of single track operation, a higher speed nonconforming train is less costly to the network. A method is proposed and demonstrated for applying this model to a practical railway network scheduling problem. When applying the model, the primary decisions are the choice of track segment boundaries and the dimension of the discrete time unit.