基于实测数据的南京地铁换乘楼梯流量系统动力学分析

System dynamics analysis on the passenger transfer tendency in Nanjing subway transfer staircases based on the actual-measured data

在实测数据的基础上,经过数据处理和分析,获得了地铁高峰运行期间换乘乘客在通道和楼梯口的速度-时间、密度-时间、流量-时间曲线。在所得统计曲线的基础上,根据系统动力学理论和方法,结合紧急疏散模型,用Vensim仿真软件建立了基于实测数据的地铁换乘系统动力学模型,并对仿真模拟后的数据进行分析,发现换乘楼梯流量随楼梯长度增加逐渐减小,并最终趋近2.5人/s;随楼梯宽度增加逐渐增大,并最终趋近5.1人/s。通过Origin软件拟合出两条曲线,并得出了流量与长度、宽度的定量关系。

The paper is aimed at providing some reference suggestions for the subway stair-case design based on the system dynamics model.For the research purpose,we have investigated the passenger transfer tendency and transfer patterns in hoping to optimize the design of the stair cases and promote efficient evacuation and the passenger safety in case of emergency.In doing so,we have managed to conduct a field survey through data processing and analysis in Nanjing Subway system,thus gaining the curves of passenger transfer in terms of speed vs time,density vs time and the passenger flow vs time in the transfer channel and stairs during the peak hours.And,then,we have managed to establish a system dynamics model for the subway transfer system via a Vensim simulation software along with the emergency evacuation model.And,afterwards,we have made an investigation of its execution through a series of scenarios of different inputs and outputs in correspondence with the passenger transfer regularity at the transfer staircases with regards to the length and width of the staircases.As a result,we have found that the passenger transfer in the staircase tends to decrease with the increase of the length of the stairs and eventually up to 2.5 pers/s.In the meantime,the passenger transfer rate via the staircase tends to increase with the increasing width of the stairs and eventually up to 5.1 pers/s.What is more,we have also noticed that the Software Origin we have adopted proves fit for the two varying curves with the two quantitative fitting equations being proposed.The resulting curve turns to be well matched with the actual situation.If the peak hour of the passenger flow can be extended to prolong the time for the passengers to leave the metro station,it would be possible to reduce the actual capacity and service level of facilities,which seems to influence the transportation power of the metro.Thus,it can be seen that the system dynamics model proposed in this paper can be expected to serve as a reference for future studies on the passenger fluency in subway system.It can also be expected to provide a guide for designing the similar staircases in metro systems.