Network Load-balancing Based High-speed Railway Network Characteristics Analysis And Line Plan Optimization

With the characteristics of safety,high-velocity,high punctuality and high-level of comfort,high-speed railway has gradually developed into the backbone of the integrated transportation system and an important component of the national economy.With the establishment of "four vertical and four horizontal" high-speed railway network and the gradual formation of "eight vertical and eight horizontal",China’s high-speed railway has officially entered the era of network operation.At the same time,the complex railway network conditions make the high-speed railway transportation organization more difficult,the factors that affect the operation characteristics and the conditions that restrict the operation benefit increase,resulting in a mismatch between transportation demand and transportation resources in the network.It is of great theoretical and practical significance to study the optimization method of passenger train line plan and balance the load pressure of each station in order to improve the overall operating efficiency and the utilization of transportation resources of high-speed railway.From the network perspective,this thesis studies the network load-balancing based high-speed railway network characteristics analysis and line plan optimization.The main contents are summarized as follows:Firstly,based on the three-layer coupling structure of high-speed railway network,a multi-dimensional network modeling and a characteristic analysis method are proposed.The physical network,train service network and transfer network of high-speed railway are established according to the complex network theory.The network topology and operation characteristics are analyzed from the aspects of connectivity,clustering and centrality.A node load pressure index is defined to describe the matching degree between the operational intensity and the operational capability of each station in the railway network.Through the network simulation of the practical high-speed railway line and current line plan,it reveales the quantitative relationship among the high-speed railway network structure,train transportation organization and system performanceSecondly,in the view of the mismatch between the transportation demand and transportation resources of each station in the current high-speed railway operation process,a load-balancing based line plan optimization method is put forward.A multiobjective nonlinear mixed integer programming model is established,which aims at improving the economic benefit,social benefit and network overall resource utilization,and the train running path plan,train stop plan,and passenger distribution plan are comprehensively optimized.Besides,a two-stage hybrid search algorithm based on genetic algorithm and particle swarm optimization algorithm is designed.Meanwhile,a network simulation example is established and it verifies that the optimization method can effectively improve the overall load balance of the network while ensuring the travel demand of passengers.Finally,considering the anti-interference ability of train running in high-speed railway network,a comprehensive evaluation method of line plan for network operation scenario is proposed.Combining the transportation characteristics evaluation method and the network characteristics evaluation method,a comprehensive evaluation system of line plan is established,which describes the operation characteristics with capability index,technical index and passenger satisfaction index,and describes the performance of the network after emergencies with the indicators of network robustness.According to the analysis of network robustness,random attack and specific attack strategies are further designed to study the evolution of high-speed railway network performance under failure scenarios.Meanwhile,a simulation experiment is carried out with the real high-speed railway network,and it is verified that the load-balancing line plan has significantly enhanced the robustness of the network,and the evaluation results can provide a decisionmaking basis for the design and optimization of line plan.This thesis has 43 figures,21 tables and 74 references.