Research On Train Operation Adjustment Under Urban Rail Transit Interruption Events

In heavily populated cities of China,urban rail transit systems transport millions of passengers daily,accounting for over 50% of the city’s total passenger traffic.During peak hours,some busy metro lines have reached a frequency of less than 2minutes between trains.Such high train service frequencies lead to a significant reduction in service levels when interruptions last for more than 30 minutes.This causes large crowds of passengers at stations,even leading to trains being stranded between stations.Accordingly,this paper proposes to study the impact of passenger flow and train operation adjustments during subway interruptions to obtain a reasonable and efficient train schedule by starting from subway interruption problems.The main research works include:(1)Research on the evaluation of passenger flow impact during urban rail transit interruptions.A redefinition of the definition of interruption events and a summary of their classification and characteristics were presented.Under normal operation and interruption conditions,the process of passenger travel behavior was analyzed;and the affected passenger types were classified into 5 categories.Ten passenger flow quantification evaluation indicators were proposed in four aspects: passenger flow smoothness,stability,balance,and spread,to comprehensively evaluate the impact of passenger flow during interruptions.(2)Research on the adjustment model of train operation during urban rail transit interruptions.The objectives of train operation adjustment were analyzed from both passenger and operational perspectives,and the applicability of commonly used train adjustment methods was discussed.Considering the constraints of train operation safety,capacity,and dynamic passenger demand,the small-block train operating adjustment method was adopted to handle interruption events.A train operation adjustment model with the objective of minimizing the total waiting time of passengers was established,and an improved genetic algorithm was proposed to solve the train operation schedule.(3)A case study was conducted on the Beijing Metro Line 5 to verify the rationality of the proposed model and the effectiveness of the algorithm based on Matlab programming.The experimental results show that the proposed model can effectively reduce the waiting time of passengers within the system and improve the service level of the urban rail transit system during interruptions.It can provide decision-making support for emergency adjustments in urban rail transit to a certain extent.