Evacuation Model And Simulation In Multiple Exits Environment

There are huge hidden danger in large public buildings such as shopping malls and stations.When an emergency occurs,it would lead to serious economic losses and even threaten the lives of people if pedestrians cannot be evacuated reasonably and quickly.At present,there are usually multiple safety exits in public buildings.Evacuation personnel can effectively select multiple exits in the shortest time to carry out safe evacuation,which is an important link to improve evacuation efficiency.Yet studied in academia for a few years,multiple evacuation simulation models were established,existing evacuation models are still lack of a corresponding exit selection mechanism.Aiming at this problem,this paper focuses on the exit choice behavior of pedestrians in a multi-exit environment.An evacuation model suitable for multi-exit environment is constructed combining with the existing simulation model.And the main research work is listed as follows:(1)The current situation development trend and relevant theory about pedestrian evacuation were introduced.(2)Three factors affecting the exit choice were determined:the distance from pedestrian to exit,the width of the exit,and the pedestrian density near the exit.(3)For the three influencing factors,the corresponding probability models were established,and the exit choice model was established by considering the influencing factors comprehensively,it focused on the influence of density factor on the choice of exit,and analysed the relationship between speed and density.According to the degree of influence of speed,the pedestrian density near the exit was divided into three levels,and the pedestrian density function is constructed.(4)Comparing and analyzing the existing evacuation simulation model,the social force model was selected as the basis of evacuation theory.In view of the shortcomings of the social force model,an evacuation model considering pedestrian panic and exit attraction was constructed based on this model.Integrating the social force model and the exit choice model,a multi-exit pedestrian evacuation model was established.(5)Simulation experiments were carried out on the established evacuation model by Matlab environment.The validity of the probability model corresponding to the influencing factors was verified.Experiments studied that relevant influencing factors and different evacuation strategies have impact on exit selection and evacuation efficiency.The results show that the overall evacuation efficiency is the highest when considering all three influencing factors.