Integrated Scheduling Optimization Of Gantry Cranes And Trucks In Railway Container Terminal

With the implementation of the "One Belt One Road" strategy and the enhancement of global environmental awareness,railway container transportation has gradually become important development targets of the comprehensive transportation system in China due to its integration of container transportation and railway transportation with the advantages of safety and environmental protection,energy-saving and convenience,wide-coverage,and low freight rates.The railway container terminal is an important supporting platform for railway container transportation,which undertakes the functions of storage,handling,and distribution of containers.The reasonable scheduling of its internal handling resources is a key factor that affects the service level,transportation quality,and operational capabilities of the railway container terminal and the entire transportation network.To improve the operation efficiency of the railway container terminal and the balance rate of the gantry cranes,a new handling scheme of "gantry cranes and trucks" is put forward for the main operation area of the railway container terminal.And a detailed analysis has been made on the connection of the operating time between gantry crane,truck,gantry cranes and trucks,and gantry cranes and gantry cranes.On this basis,with the objective functions of maximizing the balance rate of the gantry crane and minimizing the completion time of the unloading operation as the objective functions,a bi-layer nonlinear mixed-integer programming model is constructed to study two interrelated multi-level problems are study comprehensively,including the crane area division dynamically and collaborating scheduling of gantry cranes and trucks.By analyzing the characteristics of the model and decomposing the research problem,combining heuristic rules,genetic algorithms,and greedy ideas,a two-layer hybrid genetic algorithm is designed to solve the model.Finally,design an example and analyze the experimental results.For different scales,the experimental results of the dynamic crane area and three traditional division rules are compared and analyzed to verify the effectiveness of the model and algorithm,including static crane area,the equal crane area,and crane area based on the volume of equal task.Besides,for the current situation where the number of trucks does not satisfy the large-scale numerical example,considering the two factors of operating efficiency and truck start-up cost,the optimal number of the truck is solved for the large-scale calculation example.Also,to further verify the superiority of the proposed new handling scheme of "gantry cranes and trucks",it is compared with the experimental results of the traditional handling scheme of multi-gantry cranes.From the perspective of the actual operation and management of the railway container terminal,this paper proposes to use the "gantry cranes and trucks" handling scheme in the main operation area.The long-distance loaded travel of the gantry crane with poor maneuverability,slow-moving speed,and high operating cost can be replaced by a truck with high flexibility,high transportation speed,and low operating cost.And by reasonably dividing the crane area to reducing the empty travel of the gantry cranes,improve the balance rate of the gantry cranes,and maintain the performance of the gantry crane,which provides theoretical support for the actual operation management of the railway container terminal.