Modeling And Simulation Of Pedestrian Flow In Urban Rail Transit Station

Urban rail transit has become an important solution to the urban traffic congestion,with its advantage of punctuality,speediness,high efficiency,large capacity,less pollution and so on.By the end of 2014,22 cities have built 95 lines and operating length of 2900 km in our country.Taking the Beijing subway as an example,in 2000 the average daily traffic is 1.19 million,which has exceeded tens of millions by 2014.Huge pressure was brought to the rail transit station by rapid growth in traffic scale,leading to congestion and stranded at peak hour,which exposes the mismatch between station design,management and the actual traffic.Therefore,it is of great significance to consider the regularity of distribution process to ensure smoothness,improve service level and enhance distribution ability.As a starting point in this paper,improve the related theory of pedestrian flows distribution,build station distribution simulation model based on the queuing theory,and combine the intelligent algorithm with simulation model to present the method of solving the station distribution capacity and optimizing traffic organization scheme,providing a reference for design for station design and pedestrian flow organization.Concrete research content is as follows:(1)Summarize the status of current researches.Based on the achievement summary of domestic and international research on the rail transit field,the following disadvantages of present studies are concluded: much attention to the microscopic traffic simulation,but less to macro pedestrian flow simulation model,macro simulation model of distribution process is not meticulous enough,it is difficult for the station distribution capacity calculation method to take the dynamic process of the station distribution into account.(2)Improve the theoretical foundation.Analysis the station facilities,put forward a evaluation method of facilities distribution ability and coordination,analyze the propagation characteristics of pedestrian flow between facilities.Pedestrian flow characteristics embodied in overall features and space-time distribution on the station facilities on the macro,and movement on facilities for individual behavior on the micro.Researches above improved the pedestrian flow distribution theory in station,being the foundation of the follow-up study.(3)Build the station pedestrian flow distribution model.Thinking in terms of the whole station,taking facilities as simulation object,consider services and passenger flow reach law,build the services and pedestrian flow arrival model based on the queuing theory model.Build the respective queue model of service facilities,passing facilities and distributing facilities.And build the queuing network model of the station pedestrian flow distribution by Simulink.The model can output indexes like facilities coordination degree and service intensity,with the advantage of high computation efficiency.(4)Calculate and optimize the station distribution capacity.Build a station distribution capacity computing model for the highest capacity per unit time,and a station distribution optimization model for maximum distribution and minimum average distribution time.Solve it using the genetic algorithm and the NSGA II algorithm,calling the station distribution model.This dynamic algorithm takes the station distribution process into account,which overcomes the defect of previous static calculation method.(5)Case study.A case study of Hujialou Station,carry out a research for walking speed,volume,density and so on to calibrate the simulation model.Contrast the simulation results of models and actual operation indicators,verify the reliability and authenticity of the model.Provide optimization proposals for station passenger flow organization,show the practical value of the simulation model.