Dynamic Modeling And Complex Characteristics Of Pedestrian Flow With Consideration Of Complicated Building Structure And Variable Walking Environment

With the rapid development of economy, the number of crowded public place is growing, and the importance of public safety is more and more remarkable. When encountering unexpectedness, randomness and uncertainty of emergencies, the evacuation crowd often represents some characteristics of complicated psychology (e.g., panic and confusion) and behavior, which can easily induce crowd trample disasters and threaten the safety of people’s lives and properties during emergency evacuation. Therefore, it is an urgent problem to resolve how to ensure the rapid, orderly and safe evacuation of dense crowd when an emergency to occur. Additionally, it is of great importance to investigate pedestrian evacuation dynamics, explore pedestrian’s psychological reaction and behavioral law, and design effective guidance strategies and prevention measures to alleviate and avoid casualties and property losses caused by crowd jam and panic behavior. These researches have important values on engineering application as well as scientific significance. In this dissertation, based on cellular automaton model and lattice gas model, several improved pedestrian evacuation dynamics models are proposed to investigate crowd evacuation in new-style cinema, student dormitory and other buildings with complicated structure by considering visual field effect and local density of pedestrian, respectively. And the influences of the distributions of different exit positions, visual field sizes, local density and other factors on evacuation efficiency are studied via numerical simulation. Moreover, the macroscopic characteristics of crowd emergency evacuation and the corresponding formation mechanisms of pedestrian jams are also explored in detail.The main contents of the thesis are as follows:Ⅰ. Aiming at the present distinctive internal structure of new-style cinema, a new cellular automaton model is proposed to simulate pedestrian evacuation by introducing "position safety degree", which identifies the strategy of routing choice, and the influences of different internal layouts and different exit positions on evacuation efficiency are investigated.Ⅱ. Focusing on the typical student dormitory floor, a new microscopic model combining static floor field model and lattice gas model is proposed to simulation student evacuation, and the influences of the different floorplans of student dormitories and the distributions of exit positions on evacuation efficiency are studied.Ⅲ. Based on the Burstedde cellular automata model, an improved cellular automaton model is established to simulate pedestrian flow by considering dynamic change of local density of pedestrian in the surrounding environment,, and the dynamic characteristic of pedestrian flow in emergency evacuation from a hall with single and multiple exit, turning and returning channel are studied, respectively.Ⅳ. Based on the dynamic change of walking environment, an extended cellular automaton model is constructed to simulation pedestrian counter flow by taking into account the t preferential characteristics of pedestrians movement, and the influences of the size of interaction radius and some related factors are studied. Furthermore, the macroscopic movement features of pedestrian counter flow under different density are also discussed.The final chapter of this dissertation is devoted to a summary of the thesis and a prospect of further study of pedestrian evacuation dynamics in the future.