为研究地铁车站在危险源突发事件条件下乘客主观能动性和外界环境对疏散过程的影响,结合危险源场景特征对乘客疏散过程进行社会力分析,建立基于危险源的社会力模型.模型考虑了乘客的主观能动性,调整自驱动力中期望速度大小和方向的确定方法及更新规则,并针对外界环境的影响,引入危险源对乘客的排斥力.以上海地铁某车站站台层为场景进行算例应用及分析,仿真结果表明:模型能较好地模拟危险源突发事件下乘客疏散过程.为减少疏散时间,车站疏散组织工作要安排乘客合理绕行,控制危险源范围,当车站密度小时,要提高乘客期望速度,而车站密度大时,则要提高瓶颈的通行效率.
Aiming at figuring out the effect of individual initiative and internal environment of a station on evacuation processes under the circumstance of emergency, sociM force analysis of pedestrian evacuation processes in a metro station considering the effect of dangerous source was achieved and a modified social force model was proposed. In this model, by presenting a new calculation method and update rules for desired speed and desired direction in the self-driven force, pedestrian's subjective initiative was taken into account. Besides, the repulsive force between a dangerous source and a pedestrian was introduced to reflect the influence of surroundings on the pedestrian. Detailed simulations on the pedestrian evacuation processes were designed and conducted in the context of the platform of a Shanghai metro station. The results show that the model can successfully describe the characteristics of pedestrian evacuation processes in the emergency which results from a dangerous source. Specifically, in order to reduce evacuation time, station staff should take measures to lead pedestrians to make reasonable detours and prevent the dangerous source from further spreading. It is also advised that efforts should be made to increase pedestrians' desired speed when the station is in low density and to improve the efficiency of bottlenecks when the density is high.