Collaborative Scheduling Optimization of Equipment in Multimodal Transport Harbor Considering Hybrid Operation Mode of "train-yard-vessel" and "train-vessel"

Multimodal transport harbors, especially rail-water multimodal transport, have drawn much attention in recent years. There are two operation modes describing the flow of containers, namely "train-yard-vessel" mode and "vessel-train" mode. The two modes often coexist in reality, however, there is few research focusing on this hybrid mode. To solve the problem of collaborative scheduling of railway gantry cranes and trucks in a rail-water multimodal transport harbor under the hybrid mode of containers flow, a mixed integer programming model is established and a genetic algorithm (GA) is designed to generate the schedule. Results show that the model and algorithm proposed can solve the problems in a medium and large scale. When the number of containers is 40 and the proportion of quayside containers is 0.4 or 0.6, the optimal number of gantry cranes and trucks is 3 and 10 respectively. When the number of containers is 80 and the proportion of quayside containers is 0.4 or 0.6, the optimal number of gantry cranes and trucks is 3 and 13 respectively. It is found that the number of trucks has a marginal benefit for makespan and more trucks is not always better.