. Single wagon-load (SWL) and wagon groups
Marinov et al. [13, p. 7] notes that the concept of SWL ‘services is in favour of capillarity and normally implies that one wagon will form the composition of more than one train, as it completes its journey from origin to its destination’. Thus the transport of SWLs forms an important part of total supply and transport chains for Europe. Consolidation, or bundling of SWL and wagon group, is conducted from the feeder line to the rail hub, for Full Train Load between Hubs, and for block and shuttle trains. But UIC [14] reports that most of the European Railway operators are losing money with their SWL operations, although it is claimed that the RETRACK rail freight operator successfully operated such SWLs and wagon groups, by applying a hub and spoke model [15; 16] without consolidating the cargoes of SMEs (discussed in previous approach) and other major customers. Woroniuk et al. [17, p. 83] suggests that the operation of the block and shuttle trains is less complex than the operation of SWLs. They found that by employing these block and shuttle trains service on average a freight growth of 5% to 10% were achieved on some major European rail corridors. To support such services, a feeder line operator can consolidate the cargoes of SME customers at the CC at rail terminals (see figure 7), on some of the major, longer corridors. Further research is needed to explore such a crucial issue.