Research On Rail Blocking Problem Model And Optimization Algorithm Based On Network

In recent years, China’s railway is developing rapidly, the rail network is constructing constantly. The scale of network, structural complexity, passenger and freight volume are growing simultaneously. The direct consequence of those is increasing the difficulty of train operation and organization. The blocking problem is one of the important embodiments.Because of the continuous development of social economy, the contradiction between transport demand and railway network capacity has not been alleviated. Consequently, the research object of blocking problem is not limited to one trunk railway, but refers to the regional rail network and even the whole transport network. The ultimate aim is to make full use of the traffic capacity, to speed up the traffic flow distribution, to improve the efficiency of transportation, to meet the transport market demands.The traffic organization is the core content of the blocking problem. In this paper, firstly evaluate the traffic organization mode through two aspects which are time benefit and economic benefit. Followed, the method of OD traffic flow adjustment has been discussed in detail. Examine the necessary condition of blocking problem which is rail capacity. Then, according to the relative position relationship of12network marshalling stations, simplify the national freight business network. Construct the blocking problem model and simplify the model by Lagrange relaxation algorithm (LR). The problem is decomposed into two sub problems. Iterate the Lagrange multipliers by subgradient algorithm to reduce the dual gap and find a best solution we can accept. Construct a miniature rail network to explain the application and solving process of the model. Finally, design a blocking assistant decision system for Zhengzhou north marshalling station based on the basic theory research. Put forward a new concept named periodical rush group number. Speed up the traffic flow distribution by executing the freight train formation plan dynamically in periodic congestion period. Achieve the goal of making full use of network traffic capacity and meeting the transport market demands.