Optimization Of Wagon Flow Assignment With Work Division Among Multi-marshalling Stations In Railway Hub

As one of the main modes of transportation in China,railway transportation has significant advantages over other modes of transportation,such as long transportation distance,large transportation capacity and low transportation cost.With the rapid development of China’s economy,the volume of cargo transportation is rising,and the competitive pressure brought about by various modes of transportation is gradually increasing,so it is urgent to improve the transportation capacity and competitiveness of railway transportation in the new situation.As the core component of the railway hub,the marshalling station undertakes a number of technical tasks of train flow and wagon flow in the railway hub,the layout and number of marshalling stations in the railway hub will directly affect the transportation capacity and efficiency of the railway hub,and it is of great significance to rationally arrange the wagon flow assignment in the railway hub of multi-marshalling stations to accelerate the turnover of wagons,save the operating costs of the railway hub and improve the competitiveness of railway transportation.In this paper,aiming at the problem of wagon flow assignment in the railway hub of multi-marshalling stations,this paper conducts an in-depth study from the two directions of single heavy wagon flow and heavy and empty wagon flow collaborative operation.Aiming at the optimization problem of heavy wagon flow assignment with work division among multi-marshalling stations in railway hub,considering the capacity constraints of train arrival and departure,train breakup and makeup,wagons accumulation and wagons transshipping between different marshalling stations,a mathematical model is established with the minimization of the sum cost of heavy wagon flow running,disintegration and accumulation as the optimization goal,and a two-stage comprehensive optimization strategy is designed to solve the model.The strategy first uses the constraints in the model to generate a train-marshalling station matching scheme set,and then completes the optimization of the matching scheme set based on the improved discrete particle swarm optimization heuristic with genetic algorithm.Finally,small-scale and large-scale Simulation experiments are designed to test the effectiveness of the proposed strategy.Aiming at the problem of wagon flow assignment with heavy and empty wagon flow coordination operation among multi-marshalling stations in railway hub,considering the capacity constraints of train arrival and departure,train breakup and makeup,wagons accumulation and balance of empty wagon flow,a mathematical model is established with the minimization of the sum cost of the heavy and empty wagon flow entering,leaving,transshipping,disintegration and accumulation as the optimization goal,and the two-stage comprehensive optimization strategy is used to solve the model,and simulation experiments of different train sizes are designed to test the comparison and performance evaluation of the algorithm.Finally,this paper summarizes the key contents such as the problems studied,the models constructed,and the solution methods designed.Combined with the actual situation of railway freight transport,the shortcomings of this research are proposed,and the prospects of these problems are pointed out,and the direction of further research is pointed out.