Collaborative Optimization of Single-block and Double-block Train Formation Plan at Technical Stations

A high-quality train formation plan is the key to the organization of railway freight transportation. On the basis of existing studies, considering the impact of the random arrival of car flows, this paper analyzed the car-hour consumption of double-block trains with fixed and variable block weights and developed a collaborative optimization model for the formation plan of single-block and double-block trains at technical stations. The model aimed to optimize single-block and double-block trains simultaneously, to minimize the sum of classification car-hour cost of transit cars with resorting at intermediate yards, accumulation car-hour cost of single-block trains, and the total car-hour cost of double-block trains at originating yards and block-swap yards. To improve the solution efficiency of the model, linearization techniques and effective approximation of the objective function were used to transform it into linear constrained quadratic programming. The experimental results show that compared with the single-block train formation plan and the integrated train formation plan obtained by traditional step-by-step optimization approaches, the collaborative optimization model in this paper can obtain a higher quality train formation plan and effectively reduce the total car-hour consumption of car flows in the network. © 2023 Science Press. All rights reserved.