Research On The Impact Of Train Operation Modes On Train-set Utilization

With the large-scale construction of high-speed railway, the passenger transport demand is increasing, more train-sets are needed to cover the timetable. However, the train-sets are so expensive that they occupy a larger proportion in high speed railway investment, in order to save the investment and operation cost, the railway related departments hope it can cover the timetable with minimum number of train-sets and improve the train-set utilization ratios. The number of train-sets and utilization ratios are restricted to the train operation modes. This paper mainly studied the impact of train operation modes on train-set utilization, so as to have a considerable decreasing of the number of train-sets and improve the train-set utilization ratios. The main work and achievements can be summarized as follows:1. The basic features, advantages and disadvantages and applicable condition of different train operation modes were analyzed. Based on through and transfer modes, this paper constructed four train-set utilization scenes by combining different train-set utilization modes to study the impact of train operation modes on train-set utilization. Via the analysis of train-set routing basic features in this four scenes, this paper summarized the impact is concerned with whether the train operation structures are easy to form the train-set routing which contains the long and short train lines.2. Based on the train-set utilization modes of our high speed railway, this paper build the train-set routing optimization models which face single depot, multiple depots with maintenance in their own depots and multiple depots with maintenance in every depots, respectively. The modes were constructed on the transition network with the train lines as the nodes and the feasible transition arcs as the sides, considered the first level maintenance requirements both on cumulative operation time and mileage, train diagram and train-sets conservation constraints and aimed to cover the timetable with minimum number of train-sets. In addition, to improve the solving efficiency of the models, this paper proposed two transition network construction strategies to decrease the network size and reduce the number of constraints. Finally, this paper solved the modes on practical data by CPLEX software. The results show that our models and simplified strategies are feasible and efficient.3. The train-set routing evaluation indexes which including basic indexes, equilibrium degree indexes and coordination indexes were designed. With the Beijing-Shanghai high-speed railway as an example, this paper designed one through mode and two transfer modes. Via considering train-set utilization modes of the case, this paper solved and evaluated their train-set routings by the optimization models which face the multiple depots with maintenance in their own depots and the train-set routing evaluation indexes, respectively. The evaluation indexes calculation results show that the transfer modes only in some specified conditions can reduce the number of train-sets and improve the train-set utilization ratios. However, it is not mean that the higher the transfer ratios, the less number of train-sets and the more significant improvement of train-set utilization ratios.