Dynamic Modeling And Characteristic Analysis Of Pedestrian Evacuation Under The Influence Of Attraction Source

Public security is the footstone of national and social stability.In recent years,with the rapid growth of the urban population,the congestion and stampede accidents caused by the dense crowds happen frequently,which not only bring huge economic losses to the society,but also pose a serious threat to people's lives.Therefore,in case of emergency,how to ensure that a large number of people evacuate quickly,orderly and safely is a major problem to be solved.On the basis of the existing cellular automata model of pedestrian flow,as for attractive sources,different factors such as the number of attractive sources,partner behavior and different exit settings in the environment,the corresponding cellular automata models based on mobile payoff matrix are constructed respectively.Through the numerical simulation,the influences of the number,location and intensity of the attractive sources on the pedestrian evacuation efficiency are studied,and the macroscopic behavior characteristics and the generation mechanism of congestion in the process of emergency evacuation are discussed.The main contents are as follows:?.As for the single attractive source in the channel,a cellular automata model describing the influence of attractive source on pedestrians is constructed by introducing the benefits of core area and edge area of attractive source.The influences of single attractive source's location distribution,influence range,attraction intensity and space boundary range on pedestrian movement are studied by numerical simulation.The results show that the reasonable location distribution of attractive sources can avoid pedestrian flow hedging,thereby reducing the occurrence of pedestrian congestion effectively.When the attractive source is located near the exit to reduce the influence range and intensity of the attractive source can decrease the occurrence of congestion.The larger the space boundary,the longer the pedestrian evacuation time and the greater the probability of congestion will be.Therefore,in some places with a large spatial boundary,the location distribution,influence range and attraction intensity of the attractive source should be strictly controlled to reduce the occurrence of pedestrian congestion.?.On the basis of the above model,for the scenarios of double attractive sources in the channel,a new cellular automata model considering partner behavior is constructed.By the numerical simulation,the influences of double attractive sources' location distribution,influence range,the number of partner behavior among pedestrians and its location distribution on pedestrian movement are studied.The results show that when the double attractive sources are located along the same side of the passageway,the influence of the attractive source on pedestrian congestion can be reduced.The longer distance between the center of the double attractive source can give pedestrians enough time to adjust the direction of movement,which improves the movement efficiency of pedestrians.The greater the number of pedestrians in partner,the more difficult the average speed of pedestrians is to reach the expected speed.When the partners are close to the attractive sources,too many pedestrians near the attractive sources can not move normally,which will greatly weaken the movement efficiency of pedestrians.Therefore,when the double attractive sources are located on the same side of the passageway over a long distance,it is most beneficial to increase the average movement speed of pedestrians and reduce congestion.?.For the layout of exit under the influence of the attractive sources,a corresponding cellular automata model is presented.The influence of different layouts of exit on pedestrian movement efficiency under the single and double attractive sources are studied.The results show that under a single attractive source in a room,the overall evacuation time of pedestrians is inversely proportional to the number of exits.The more exits there are,the shorter the evacuation time is.When the single attractive source is located near the exit of the room,the congestion near the exit will greatly increase the overall evacuation time.For the case of double attractive sources in a room,the larger the distance between two attractive sources,the shorter the overall evacuation time,and the higher the evacuation efficiency.Finally,the summary and prospect of this thesis are given.