Solving the train formation plan network problem of the single-block train and two-block train using a hybrid algorithm of genetic algorithm and tabu search

This paper presents a formulation and solution of the railway freight Train Formation Plan (TFP) network problem in China using both the single-block trains and the two-block trains. Firstly, the single-block TFP model is established under given shipment demands, classification capacity and track quantity at the yards. Then the benefits which can be achieved by replacing single-block trains with two-block trains are systematically analyzed and summarized. The comprehensive optimization model of the train formulation plan using both the single-block trains and two-block trains is established aiming at the minimization of the total car-hour consumption at all yards. A hybrid algorithm of genetic algorithm and tabu search is developed to solve the single-block TFP model and then a greedy algorithm is proposed to replace single-block trains with two-block trains. Finally, the model and the solution approach are tested in an actual 19-yard railway sub-network in China.