行为波动下的人群紧急疏散建模及特性研究

发布时间：2018-08-22 14:03

【摘要】：近几年来随着我国社会经济的发展进程不断的加快,居民对社会活动的需求越来越大,这些社会活动所需的公共场所行人分布比较密集,且流动性大。因此,涉及的行人安全问题已成为一个亟待解决的热门问题。本文在行人流费用势函数场元胞自动机模型的基础上,针对突发事件下行人应急疏散问题,考虑不同于正常疏散情况下行人群体特有的心理特征(如恐慌、冲动、从众等),分别建立了一般场景、行人对流、可视能力较差三种场景下行人应急疏散元胞自动机模型,通过数值模拟与分析,探讨了三种场景下行人心理变化等因素对行人流宏观行为特性及疏散动力学机制的影响。此外,还为行人流安全应急疏散及建筑设施的规划提出相关的依据。本文的主要工作如下:一、考虑紧急疏散情况下,行人的心理紧张程度对行为波动的影响,提出了一种扩展的含行为波动效应的费用势函数场元胞自动机模型。研究不同密度下行人的紧张程度幅度、不同行为波动人群比例等因素对行人流应急疏散的影响,并探讨了紧张程度影响下的行人流宏观现象的生成机理。在行人流费用势函数场的基础上,结合一般行人心理特征所表现的恐慌、冲动等行为,引入行为波动的量化公式来反映行人心理的紧张程度导致的行为变化,扩展不舒适度函数,建立含行为波动效应的行人紧急疏散费用势函数场元胞自动机模型。数值模拟研究行人行为波动参数对疏散效率的影响,并对行人疏散过程中的典型时空动力学特性进行了讨论。结果表明:与正常疏散相比,突发事件下紧张程度引起的行人行为波动并不一定会引起疏散效率的降低;在低密度下,行为波动的增加可以减少疏散时间,提高疏散效率,而在高密度下,行为波动幅度的增大则会导致疏散效率显著下降;疏散人群中,受行为波动影响大的人群比例增加时,疏散时间随之增加;此外,系统的尺寸对疏散效率无明显影响。二、将上述提出的含行为波动效应的费用势函数场元胞自动机模型进行拓展,研究紧急状况下通道中的相对行人流,探讨紧张程度幅度、左右行人的不对称效应等因素对行人运动的演化规律及相变影响。基于上述建立的含行为波动效应的费用势函数场元胞自动机模型,考虑突发状况下心理紧张程度对左右两组行人群体运动特征的影响及通道中行人偏右行走的习惯,建立了模拟紧急状况下的相对行人流势函数场模型。数值模拟再现了正常状态下相对行人流常见的分层、成行及相分离现象。此外,同正常状态下相比,紧急情况下适度的紧张程度会延缓堵塞的形成;当行人处于极度紧张状态下,混乱无序非成行现象被观察到;两组行人比例的不对称性将提高过渡相到堵塞相转变的临界密度,进而延缓通道系统被完全堵塞的时间。三、考虑行人视野受限的客观环境,提出了可视度函数,建立了描述行人视野受限影响的费用势函数场元胞自动机模型。研究心理紧张程度、可视度半径、行人密度等因素对行人应急疏散的影响。针对行人视野受限的客观环境,考虑到行人视线受限将会导致不舒适度费用的增加,提出可视度函数,建立了行人视野受限影响下的费用势函数场元胞自动机模型。数值模拟研究了紧张程度、可视度半径、密度等因素对行人流应急疏散的影响。研究表明:紧急疏散过程中,可视能力半径越小,疏散效率越低;可视能力半径不同,紧张程度对疏散效率的影响也不同。最后对全文进行了总结和展望,并指出今后需要进一步研究的问题。
[Abstract]:In recent years, with the acceleration of social and economic development in China, the demand for social activities is increasing. The pedestrians in public places required by these social activities are densely distributed and have great mobility. On the basis of several-field cellular automata model, aiming at the emergency evacuation of pedestrians under emergencies, considering the peculiar psychological characteristics of pedestrians (such as panic, impulse, conformity, etc.) which are different from those under normal evacuation, the cellular automata model of pedestrian emergency evacuation under general scene, pedestrian-to-pedestrian flow and poor visibility is established. Through numerical simulation and analysis, the effects of pedestrian psychological changes on pedestrian macroscopic behavior and evacuation dynamics in three scenarios are discussed. In addition, the relevant basis for pedestrian safety emergency evacuation and building facilities planning is also proposed. An extended cost potential function field cellular automata model with behavior fluctuation effect is proposed to study the effects of the degree of tension and the proportion of people with different behavior fluctuation on pedestrian emergency evacuation under different densities. On the basis of the potential function field of pedestrian flow cost, combined with the panic and impulse behaviors of pedestrians'psychological characteristics, the quantitative formula of behavior fluctuation is introduced to reflect the behavior changes caused by pedestrian psychological tension, expand the uncomfortable degree function, and establish pedestrian emergency relief with the effect of behavior fluctuation. Cellular automata model of evacuation cost potential function field.The influence of pedestrian behavior fluctuation parameters on evacuation efficiency is studied by numerical simulation,and the typical spatio-temporal dynamic characteristics of pedestrian evacuation process are discussed.The results show that the fluctuation of pedestrian behavior caused by the degree of tension under unexpected events does not necessarily lead to evacuation compared with normal evacuation. In low density, the increase of behavior fluctuation can reduce the evacuation time and improve the evacuation efficiency, while in high density, the increase of behavior fluctuation amplitude can lead to a significant decrease in the evacuation efficiency; in evacuation population, the proportion of people affected by behavior fluctuation increases, the evacuation time increases; in addition, the size of the system on the evacuation efficiency. Secondly, the proposed cost potential function field cellular automata model with behavioral fluctuation effect is extended to study the relative pedestrian flow in the corridor in emergencies, and to explore the effects of the degree of tension, asymmetric effects of left and right pedestrians on the evolution of pedestrian movement and phase transition. A cost potential function field cellular automata model with behavioral fluctuation effect is established. Considering the influence of psychological stress on the movement characteristics of the left and right groups of pedestrians in sudden situation and the habit of pedestrians walking to the right in the passage, a relative pedestrian flow potential field model is established to simulate the emergency situation. In addition, moderate tension in emergencies delays the formation of congestion compared with normal conditions; when pedestrians are in a state of extreme tension, disordered non-line formation is observed; and the asymmetry of the ratio of two groups of pedestrians increases the transition phase to the congestion phase transition. Thirdly, considering the objective environment with limited pedestrian field of view, the visibility function is proposed, and the cost potential function field cellular automata model describing the effect of limited pedestrian field of view is established. Aiming at the objective environment with limited pedestrian visual field and considering that the cost of discomfort will increase due to the limited pedestrian visual field, this paper presents a visibility function and establishes a cellular automata model of cost potential function field under the influence of limited pedestrian visual field. The results show that the smaller the visibility radius, the lower the evacuation efficiency; the different visibility radius, the different degree of tension on the evacuation efficiency.
【学位授予单位】：太原科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：D035

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