Shunting yard operations: Theoretical aspects and applications

Almost ever since freight has been transported via rail, shunting yards (also called classification or marshaling yards) are operated in order to separate freight trains and reassemble new trains. The efficient use of shunting yards has a deep impact on the efficiency and reliability of rail freight services. Thus, much research on shunting yards has been published, starting from the 1950s. Lately, several publications mostly focusing on the sorting procedures have livened up research on shunting yards. This paper reviews the literature on the operational processes at shunting yards over the last 40 years and discusses the operational challenges of freight transshipment. The approaches are classified according to different sorting strategies which allows an easy access to the models for both, researchers and practitioners. The paper concludes with an overview on future research challenges.

► In this survey we consider for the first time the entire operations of a shunting yard.
► We discuss theoretical insights and the influence of practical requirements on the structure of decisions.
► We present models for predicting yard performance or minimizing dwell time of railcars.
► We further consider minimizing the number of classification tracks used for sorting.
► Sorting might require several time-consuming track pulls which are to be minimized.