A preliminary prototyping approach for emerging metro-based underground logistics systems: operation mechanism and facility layout

Developing a metro-based underground logistics system (M-ULS) to integrate freight activities into passenger rail transit networks is a sustainable option to improve urban traffic and mobility. This paper proposes innovative concepts for M-ULS prototypes. The system design uses knowledge from engineering practice, emerging initiatives, literature, and experts' viewpoints. First, demand flows, hierarchies, and facility features of an M-ULS network are described, based on which the collaborative mechanism of shared metro passenger-goods transport, along with specialised packing and transportation strategies, are modelled and compared. Both overground and underground measures are envisaged for last-mile deliveries from metro to customers. Second, a hierarchical framework incorporating 37 key technologies that are necessary for M-ULS development is organised and evaluated. Third, interior layout schemes of a specific interchange metro station with logistics functions are designed. Underground space partitions at the platform layer and the station hall layer are visualised. The logistics workflows of the station are described in full. Evidence from literature and surveys indicates that the proposed M-ULS models are technically feasible, and their advantages and disadvantages are clear. This study contributes to providing a holistic decision support tool for the future planning and design of M-ULS and other rail-based freight transportation systems.