Research On Counter-Current Behavior Of Evacuation Based On The Social Force Model

Once an emergency occurs in public places,the consequences are extremely serious.Therefore,evacuation and safety issues in the public sphere have attracted wide attention.In the process of evacuation of personnel,some individuals have the counter-current behavior because they want to retrieve their valuables,rescue vulnerable groups or low quality of individuals.This will cause blockage of the passages,crowd formation,and casualties.Therefore,this paper focuses on the characteristics of counter-current behavior and its impact on the process of evacuation,providing evaluation for the design of existing buildings and the guidance for the design of buildings to be built.Firstly,we analyze the characteristics of individual counter-current behavior,and divide the behavior of counter-current into two categories: target static counter-current and target moving counter-current.And build the individual counter-current behavior decision-making framework based on social force model respectively.We also use the computer technology to simulate the individual counter-current behavior of two exit rooms,and analyze the effect of this behavior on evacuation process.Secondly,we analyze the characteristics of small group counter-current behavior,and divide the small group counter-current behavior into two categories: small group with no leader counter-current and small group with leader counter-current,and establish the decision-making framework of the small group counter-current behavior.For multi-exit rooms,the individual selection exit model is established.Then we establish the model of small group members determining the target location of next step.Combining with the characteristics of small group counter-current behavior,the behavior is simulated,and the influence of counter-current of small groups on evacuation process is analyzed.Finally,we analyze the characteristics of personnel counter-current behavior in emergencies and the behavioral characteristics of people gathered in panic.We define the panic degree to describe individual psychological panic degree quantitatively,and establish the formula between the individual desired speed and panic degree.Combining the decision-making framework of individual counter-current behaviors and small groups counter-current behaviors,we establish the counter-current behavior model under panic state,and analyze the effect of this behavior on evacuation process.We establish a simulation platform for evacuation in venues to simulate counter-current behavior in normal and emergency situations.The simulation results show that the proposed simulation model based on social force model is feasible and can reproduce and explain the real evacuation situation.