Study On The Passenger Gathering Degree On The Station Platform Of Urban Rail Transit

With the characteristics of closure property, limited space and the complexity of inner facilities, the urban rail transit station also appeared the situation of serious passengers’ aggregation in the peak hours with a larger passenger flow. As the housing facilities for passengers getting on and off in the station, the platform was the most obvious for the phenomenon of passengers gathering. The platform will occur some serious security incidents such as congestion and stampede if the passenger aggregation exceeded the upper limit capacity of the platform, which threatened the safety of the passengers, and affected the normal operation of the station. Therefore, it is of great significance to study the passenger aggregation of the platform.With the analysis of four stages of passengers entering into the platform to wait for the train, getting off the train, getting on the train, as well as get off passengers leaving the platform in a departure interval, the paper abstracted the platform into a rectangular space,described the passengers entering into the platform and getting off the train as the input stream while the passengers getting on the train and get off passengers leaving the platform as the output stream. As the carrier of the passenger aggregation on the platform, the internal space and external space providing the input and output stream of the platform were discussed respectively. The platform was the subject of the passenger aggregation, the characteristics of the passengers on which were analyzed. Considering the passengers traffic characteristics, the passenger aggregation on the platform was defined borrowed from the traffic flow theory and the calibration of station level of service. It gave the passenger aggregation state classification of the drop zone and walking areas on the platform. The passenger aggregation was divided into four states: free flow, steady flow, saturated flow and forced flow using the indices of space occupancy and flow density of the passengers. Then the paper analyzed the state grading of the passenger aggregation of four stages in a departure interval, and the laws of different stages appearing different states, with the passengers aggregation curves to reflect, as well as analyzed the rules of appearing passengers stranded on platform. Based on the proper state grading table of passenger aggregation on the platform, calculations in defined conditions are given in different states of different stages, and the critical values of theaverage rate of passengers entering into the platform when appearing passengers stranded on platform are given, which can provide a theoretical basis for making the operation plan and the station flow control measures.Finally, through an example calculation and analysis of passenger aggregation on the platform in the Xi’an Subway Line 2 SHI TUSHUGUAN station at the morning peak hours,based on the proper state grading table of passenger aggregation on the platform, calculations in defined conditions are given in different states of different stages, and the critical values of the average rate of passengers entering into the platform when appearing passengers stranded on platform are given, which can provide references for the station flow control measures.