Optimization of yard remarshalling operations in automated container terminals

When an automated container terminal (ACT) yard is busy, the loading, unloading, container retrieval, and grounding of different liners may be performed in the same time window, which can lead to conflicts in yard crane operations on the seaside and landside, greatly affecting loading and unloading efficiency. Consequently, the problem of allocating containers in advance based on the state of the containers using a container remarshalling process when the yard cranes are idle (to avoid yard crane conflicts and improve yard crane efficiency during busy hours) needs to be resolved. In this study, a container remarshalling optimization model for improving the efficiency of outbound containers based on known import and export information was developed. By considering the time savings and remarshalling costs, the number of remarshalled containers and target bays for container remarshalling were determined using the proposed method. This study also examined remarshalling operational strategies in different scenarios. Furthermore, a real-world ACT case study proved that the proposed method and mathematical model could effectively shorten the outbound time, providing detailed solutions for ACT remarshalling operations.