Research On The Influence Of Train Operation Structure On The Section Carrying Capacity For High Speed Railway

With the continuous growth of high-speed railway passenger number,some high-speed railway line's transport capacity in the middle/east China has been becoming increasingly tense.At the same time,China's high-speed railway network has the characteristics of "more points,long lines and large coverage",which makes the train operation structure complex and diverse,and the complicated train operation structure influences the section carrying capacity deeply.Therefore,a reasonable adjustment of the train operation structure and an optimization of the transport organization is an important way to ease the tension of the railway line's transport capacity.This paper mainly studies the influence of train operation structure on the section carrying capacity for high speed railway,analyzes the existing problems of existing train operation structure,and puts forward the measures to optimize the structure of trains and improve the section carrying capacity.Firstly,the definition of the train operation structure is defined,and the main factors influencing the section carrying capacity in the train operation structure is analyzed,which lays the theoretical foundation for follow-up work of the research.Secondly,the paper presents the characteristics of the research methods on the section carrying capacity,and combined the objective of the paper,the high-speed railway section carrying capacity calculation model which can quantitatively analyze the influence of the train operation structure on the section carrying capacity is established.The model is an integer programming problem,which maximizes the utilization of capacity as the goal and learns UIC406's idea on the train timetable's compression,and the objective function is described as minimize the sum of train's arrival time at the end station of the designated section,which the designated station can choose the terminal station of each train for global optimization or the middle station for specifid segment according to the actual needs.Thirdly,a precise algorithm,the Branch and Bound based on the optimal estimation,is used,and the paper design a Segmentation and Scroll strategy simultaneously to draw the train timetable piecewise,which could solve the scale problem.The algorithm is implemented in CPLEX Optimization Studio software using OPL language,and the visualization and index statistics of train timetable are realized by MATLAB.Finally,the Beijing-Shanghai high-speed railway's train plan in January 2017 is taken as a case to verify the effectiveness of the above method,the established train timetable's occupancy time and operation indexs for Xuzhou-Bengbu section(tensest capacity section in all section of Beijing-Shanghai high-speed railway)capacity utilization optimization and for global optimization in the Beijing-Shanghai high-speed railway.Then,according to the main factors influencing the section carrying capacity in the train operation structure,the different scenes of the train operation structure,including the departure time domain,the cross-line train's ratio,the differernt stop type ratio and the trains' speed grade difference,are designed in order to analyze the main characteristics of train operation strucure's influence on the section carrying capacity,and the suggestions are put forward to optimize the train operation structure.