Optimization of freight flow allocation and decision making for high-speed rail express services considering freight-dedicated train

Based on the development trend of China's high-speed rail express and the demand of various time-sensitive cargoes, a mixed-integer programming model integrating the decision making of freight dedicated train operation and freight flow allocation is constructed, considering two modes of piggyback transport and high-speed express dedicated train, with the aim of minimizing operating costs, and solved by using Gurobi business optimizer. A case study is carried out using some high-speed express mainline networks in China to determine the number and route of dedicated freight trains, as well as the freight flow allocation schemes of different modes. The results show that under the condition of limited capacity of the transport network, reasonable allocation of piggyback and dedicated train freight flow can better meet the transport needs of different timeliness express. Compared with the existing single piggyback transport mode, the mixed mode of piggyback transport and dedicated train transport can significantly reduce the cost of high-speed rail express, in which the average cost of the next morning express is reduced by 12.7%.