Experimental And Simulation Study On Evacuation Behavior Of Pedestrian On The Stairwell Based On 3D View

The stairs as an important part of urban traffic evacuation,is widely used in all kinds of buildings.In the emergency situation such as power failure,fire and earthquake,the elevator may cause unforeseeable damage to personnel evacuation,and the staircase will become the only evacuation passageway.In the case of emergency,the staircase area is prone to overcrowding and mass stampede.In conclusion,the staircase is both an evacuation passageway and an evacuation bottleneck area.Therefore,it is of great practical significance to study the behavior characteristics of personnel evacuation on the stairwell and make scientific evacuation strategies.From the three-dimensional perspective,we firstly carried out series of evacuation experiments on stairwell under different conditions,and we use the video processing technology,extract the personnel's trajectory,the typical evacuation speed,density and flow characteristics can be analyzed.Finally,we conduct the simulation with the modified 3D social force model and give some evacuation strategy advices.The main research work is as follows:The main research work is as follows:(1)Carry out the ground-walking experiment,straight line and circle walking experiment on the stairwell.The experiment shows that when the pedestrian is moving,there are obvious oscillations in both horizontal and vertical directions,and their trajectories can be fitted well with the sine function.And when the pedestrian moves on the steps,the amplitude of the track is negatively linear with the speed,whereas the swing frequency becomes a positive linear relationship with the velocity.What's more,Pedestrian's footsteps may be constrained by the steps,which will cause their microscopic velocity distribution appearing the "ladder shape".(2)Conduct observation on the movement behavior of pedestrians on the stairwell under normal conditions.The results show that the average downstairs speed is higher than that of upstairs under normal condition and the speed of pedestrians is negatively linear with population density——the higher the density is,the lower the speed is.Besides,gender,age,group and other factors have a significant influence on the speed of the pedestrian while carrying luggage has no significant influence on the speed of the pedestrian.(3)The evacuation experiment of different number of people in the staircase area is primarily carried out in the case of emergency.The results show that the upstairs speed is higher than that of downstairs when escaping,because the downstairs density of the pedestrians is greater,which make downstairs flow of pedestrians larger,so the downstairs evacuation efficiency is higher.And the microscopic speed,density and flow rate of the up and down stairs will be distributed with the staircase structure.(4)Finally,we put forward an improved three dimensional social force model,the simulation of the normal and emergency evacuation scenario,trajectory,and evacuation efficiency characteristic proves the rationality of the model and parameter settings.On the basis of simulation,under normal condition,the evacuation efficiency of the people with disordered,orderly and separated strategy is studied.Besides,under emergency condition,the effect of the number of evacuees,the expected speed,the width of the staircase,and the middle partition board on the personnel evacuation efficiency is also studyed.