Research On The Optimization Of Urban Rail Transit Standby Train Deployment Scheme Under The Condition Of Large Passenger Flow

In order to accelerate the construction of a strong transportation country,ensure the highquality development of transportation and stimulate the attractiveness of urban public transportation,this paper establishes the optimization method of multi-scene standby train placement scheme under the condition of large passenger flow based on passengers.It is of great significance to optimize the configuration,develop and adjust the train capacity placement plan and improve the service level of urban rail transit.The paper analyzed the causes of heavy passenger flow and the classification of heavy passenger flow stations,and summarized the causative factors of congestion.It analyzes the flow fluctuation and cross-sectional distribution characteristics of regular and sudden heavy passenger flows in two dimensions: time and space,divides the initial stage of occurrence,peak gathering stage and dissipation stage of heavy passenger flow propagation,and analyzes the main factors affecting the operation organization of heavy passenger flow.The paper analyzed the conditions for putting in the standby trains of urban rail transit.From three aspects,namely line conditions,passenger flow conditions and existing train operation scheme,the composition and main technical indexes of each condition are studied,as well as the interrelationship with standby train deployment.The principles of the use of standby trains,the principles of the timing of use and the principles of the form of application are proposed,so as to rationalize the way of standby trains and the optimization of the scheme,and to provide a reference for the idea and path for the establishment of the optimization scheme of standby trains based on different scenarios.The paper studied the optimization scheme of standby train deployment in the mode of small and large interchanges for the evacuation of weekday tidal heavy passenger flows.Based on the multi-objective nonlinear integer programming method,the standby train deployment station situation is reduced to 0/1 decision variables for the bottleneck of large and small interchanges in tidal passenger flow operation.With the objectives of minimizing passenger waiting time and maximizing train delivery capacity,the optimization model of standby train deployment for tidal weekday heavy passenger flow in large and small interchange mode is established with the constraints of safe tracking interval,train stopping time,standby train stopping time,and the ratio of large and small interchange operation.The particle swarm optimization algorithm with penalty function is used to solve the specific traffic scheme.The validity of the model is verified by taking the direction of Nanjing Metro Line 3 from Linchang Railway Station to Mozhoudonglu Station as the example,and the case proves that it has a certain optimization effect to put the standby train at the right time at Station 4 to cope with the tidal heavy passenger flow congestion,reducing the waiting time by 1721 s and optimizing the efficiency by 6.32%.The paper investigated the optimization scheme of standby train deployment for the relief of unexpected large passenger flows under the large station express mode.In view of bottleneck in the operation of large station express trains in different lines,the method of placing standby trains without stopping directly to the station of sudden passenger flow is adopted.With the objectives of minimizing the waiting time and travel time and the constraints of train safety tracking,interval travel time of standby trains,and the ratio of fast and slow trains,the optimization model of the standby train deployment scheme is established for the sudden large passenger flow in the large station express mode.The particle swarm optimization algorithm with penalty function is used to solve the specific travel scheme.Using Nanjing Metro Line S1 Nanjingnan Railway Station to Konggangxinchengjiangning Station as the example,The results show that the optimization effect of placing standby trains at the right time at station 5to cope with the sudden large passenger congestion is certain,reducing the waiting time by36761 s,and the optimization efficiency is 16.12%.