为了有效模拟研究初始分布非均匀的行人流疏散问题,通过定义行人方向模糊可视域,改进了场域元胞自动机模型。模型中,行人的目标位置选择受到方向模糊可视域内行人之间的排斥力和吸引力、出口处行人分布、距可选位置相对距离三种因素共同作用。研究表明,改进模型能够有效地实现初始分布非均匀的行人流在疏散过程中的动态平衡;改进模型不依赖于各因素的影响系数,从而避免了影响系数量化过程的主观性和疏散系统的限制性;在疏散过程中,如果行人保持一个较大的视野半径,疏散系统能够实时提供出口处行人分布状态,就可以有效地提高行人流疏散效率。该研究有助于相关行人流疏散策略和方案的制定。
In order to effectively simulate pedestrian flow evacuation with asymmetrical pedestrian distribution,this paper defined the direction fuzzy visual field to improve the floor field cellular automata model. When a pedestrian chose the next target position,his behavior was affected by the repulsive force and the attractive force between pedestrians in direction fuzzy visual field,pedestrian's distribution in exits,and the shortest distance from a pedestrian to the target position. Simulation results indicate that the modified model can achieve the dynamic evacuation balance in the process of movement with asymmetrical pedestrian distribution. It does not have to rely on the influence coefficient of every factor. Therefore,it avoids the subjectivity and the limitations of evacuation system in the process of making these factors. Moreover,if pedestrians can keep a lager radius of view in direction fuzzy visual field and real-time master pedestrian's distribution of exits,these should effectively improve the evacuation efficiency of pedestrian flow. The present study is helpful for devising evacuation strategies and schemes in buildings that are similar to this pedestrian flow.