A strategic model of freight operations for rail transportation systems

This paper formulates and analyzes a new strategic model for freight rail transportation systems. The objective of the model is predicting equilibrium flows and levels of service, given origin-destination (O-D) transportation demands for a set of different products. The model has the following distinctive characteristics: (1) a detailed representation of different freight rail yard operations is made and railway services with their operational characteristics are considered explicitly; (2) priorities are assigned to different types of freight cars to be moved, depending on the products transported; (3) the distribution of empty freight cars and their assignment over the rail network is treated simultaneously with the assignment of products to be transported; and (4) capacity constraints are considered for the movement of various products. Solution approaches are discussed. The model can be used to evaluate freight railway systems, including yard operations and rail services management policies.