人群分区疏散优化算法研究

Study on the optimization algorithm of the crowd partition evacuation

在疏散过程中,出口利用不均现象时有发生,距离最短路径并不一定是最快的路径。提出了大规模人群分区疏散优化算法,该算法以疏散时间最短为目标,综合考虑了人群分布、出口位置、出口宽度等因素,通过迭代计算,求解每个行人的最优出口选择,从而得到优化疏散分区结果。以具有多个出口的某大型步行商业街区疏散为例,利用经典的无后退有偏随机行走模型进行模拟计算,对是否采用优化分区的疏散时间进行了比较分析。结果表明:采用优化分区疏散时,部分人员放弃路径最短的疏散出口,而被导向选择宽度较宽和附近人员密度较低的出口,从而提高整体疏散效率。该算法解决了以距离最短为目标的疏散分区方式导致的出口利用不均和不充分的现象,有效提高了疏散效率,对于区域分区疏散策略的制定具有一定指导意义。

The inequality of exit capacity have occurred in emergency evacuation case. The minimum- distance route may not be the minimum- time route. In this paper,an optimization algorithm of the crowd partition evacuation is proposed,which aims at the shortest evacuation time with considering the pedestrian distribution,exit position,exit width. The iterative method is used for solving the optimal exit choices for each pedestrian and presenting the optimized evacuation partition. Taking a commercial street as an example,the classical biased- random walk model without back- step is applied to simulate the evacuation process and the evacuation times with optimized and non- optimized evacuation partition are compared and analyzed. The results show that when adopting the optimized evacuation partition,some people no longer choose the exit with shortest distance,but the wide exit or the exit with low occupant density around,then the overall evacuation efficiency increases. The algorithm solves the problems of uneven and inadequate utility of the exit in non- optimized route where the shortest distance is considered as the goal of the evacuation. Therefore,the algorithm effectively improves the evacuation efficiency,and can be widely used in guiding the evacuation partition strategy.