Research On Characteristics Of Pedestrian Flows In Y-shaped Passage

For a long time,the study of pedestrian flow in Y-shaped passage,which often appears in buildings,is limited to the study of confluence in simulation and experimental environment.Therefore,this paper investigates the Y-shaped passage in Chengdu Renmin North Road subway station,collects pedestrian flow video data,and uses multi-target tracking model,coordinate system conversion model and coordinate correction model to convert the video data into pedestrian coordinate space-time data in the world coordinate system.Based on these data,the following research is carried out:The trajectory relationship between pedestrian flows in different directions is studied.It is found that the probability of right turn pedestrian flow winning the shortest right of way at the corner is about three times that of left turn pedestrian flow;When passing through the intersection,the distance between pedestrians and the corner of the wall presents an exponential distribution within a certain range;The separation points,confluence points and conflict points of pedestrian flows in all directions are distributed outside the intersection.The fundamental diagram of the intersection and that at different positions are obtained.It is found that the fundamental diagram is different from the previous research,and the fundamental diagram after eliminating the resident pedestrian speed by cluster analysis is basically consistent with the previous research;When the density is greater than 1.2persons/m~2,the speed begins to change significantly with the increase of density.The spatial preference and density distribution characteristics of pedestrian flows in the passage are studied.It is found that the maximum relative density of right turn pedestrian flow appears near the corner,while that of left turn pedestrian flow is far away from the corner.It is found that the space of pedestrian flow in other directions will be squeezed by the main pedestrian flow.When other pedestrian flows are at the same entrance as the main pedestrian flow,the density of pedestrian flow in other directions will also increase.It is found that the average density of pedestrian flow shows a linear decreasing trend on a straight line passing through the corner of the wall.The curve fitting function of the density changing with the position at the corner is determined.It is found that along the main pedestrian flow direction,the rising speed of the density within one meter before reaching the corner density peak is about 1.5 times the falling speed of the density within one meter after reaching the peak.The characteristics of velocity distribution in the passage are studied.The characteristics of velocity distribution are analyzed by linear interpolation method,function fitting method and nearest neighbor average method respectively.It is found that stopping pedestrians have a preference to stay against the wall,and the"prospect—refuge"theory can explain this preference;At the same location,the flow velocity of right turn pedestrian flow is higher than that of left turn pedestrian flow,and the greater the density,the greater the difference of flow velocity;In the Y-shaped passage,the velocity of pedestrian flow in all directions is high on the centripetal side and low on the centrifugal side;The speed influence between pedestrian flows is overall,not only on the spatial intersection of opposite pedestrian flows.For the design of Y-shaped passage,it is suggested that the width of the intersection entrance of the main pedestrian flow path should be widened to reduce the mutual extrusion between pedestrian flows;Design the waiting area for pedestrians to stay and guide them to stay orderly;When designing the escape passage,try to use the right turn passage.For the management of Y-shaped passage,it is suggested that the design of pedestrian guidance signs should be concise and comprehensive;The site code for epidemic prevention shall be posted at the entrance of the station.