Research On Simulation And Prevention Of Stampede In Congestion Evacuation In Pedestrian Facilities

With the improvement of the economic level of society,various large-scale commercial buildings,transportation hubs and other infrastructure are developing towards the goal of high efficiency,comprehensiveness and integrated.The construction of large-scale walking facilities has reduced the cost of social organization activities and made it easier for people to gather together,which has caused a general phenomenon of clustering in life.Highly crowded places have extremely high requirements for personnel management.In the event of accidents such as earthquakes and fires,emergency and efficient evacuation of personnel are the basic prerequisite for ensuring personnel safety.During the emergency evacuation process,the large number of people,pedestrian panic,and improper management can easily lead to crowded stampede near the evacuation bottleneck.Crowded stampede has the characteristics of suddenness,unreproducibility,and danger,and it is difficult to collect on-site data of stampede.Therefore,it is a main method to study crowded stampede based on computer simulation.However,related researches are more focused on the causes and preventive measures of crowded stampede.The research on the internal mechanism of crowded stampede is relatively insufficient.This paper establishes a simulation model of crowded pedestrian flow based on the combination of spatially subdivided cellular automata and force,and explores the phenomenon of crowded stampede of evacuation pedestrian flow in pedestrian facilities.Excavating the crowded stampede mechanism not only helps to explore the macroscopic phenomenon and micro behavior characteristics of pedestrian flow,but also provides theoretical and technical support for pedestrian facility design and pedestrian safety management.The main research contents of this paper are as follows:(1)Establish a basic simulation model.Based on the spatially subdivided cellular automata model,this paper defines the rigid part and the elastic part of pedestrians,and realizes pedestrian elasticity processing.Combining the mechanism of force and the mechanism of crowded stampede,build a basic simulation model and evolution rules.(2)Analysis of the force in crowded stampede.Through the analysis of the force in the crowded pedestrian flow,the starting scenarios and conditions of the push force and friction force are explored.The panic coefficient is introduced to describe the degree of panic of pedestrians,and the relationship between the panic coefficient and push force is analyzed.By establishing the rules for the absorption,decomposition,transmission and injury of the push force,the interaction relationship between pedestrians is analyzed.(3)Research on the mechanism of crowded stampede.Based on the analysis of the characteristics of push force and friction force,a probabilistic selection mechanism is constructed to solve the problem of pedestrian movement conflicts.Excavated the trigger conditions,evolution process and the internal mechanism of the continuous stampede phenomenon.Build simulation rules based on mechanism analysis to simulate and reproduce the crowded stampede process;(4)Comparative analysis of simulation and experiment.Compare the results of the simulation model in this paper with the pedestrian experiment,and verify the effectiveness of the simulation model from the three aspects of pedestrian distribution,pedestrian evacuation trajectory and evacuation time;(5)Research on the prevention of crowded stampede.Based on the previous investigation of the internal mechanism of crowded stampede,combined with the analysis of the causes of crowded stampede,this paper proposes three preventive measures from the perspective of evacuation space design,and simulates the effectiveness of the preventive measures.