火灾情况下某城市地铁换乘站内大规模人群疏散特征研究

Simulated study on the emergency evacuation control features of the massive crowd in some subway transfer station

近年来,地铁出行已成为居民出行的重要途径,但地铁带来便利的同时,也产生了地铁站火灾和消防安全的问题。地铁换乘站是一种人流量大、空间复杂的地下空间,一旦发生火灾,人员疏散困难,极易发生群死群伤的重大灾害性事故。开展了火灾情况下某城市地铁换乘站内大规模人群疏散特征研究,选取某个地铁换乘站作为计算仿真案例,对地铁换乘站内的建筑环境进行调查,确定出该地铁换乘站内的待疏散人数、疏散人群特点及疏散通道限制条件;运用人员疏散模拟软件Pathfinder分别对高峰时期和列车满载这2种不同疏散规模进行了仿真模拟,在16个火灾场景下分析了地铁换乘站火灾情况下大规模人群疏散的瓶颈,获取了火灾情况下某城市地铁换乘站内大规模人群的疏散时间;并根据疏散瓶颈,优化了人员疏散的路径,缩短了总疏散时间,发现在高峰情况下,人员疏散基本满足地铁设计规范的6 min要求。

The current paper is aimed to analyze and identify the evacuation features of the full passenger on-board in case of a disaster of a subway transfer station,particularly involving the relationship between the evacuees and the limited evacuation outlets in the urgent moments. For the research purpose,we would like to identify and clarify such disastrous evacuation characteristics by simulating and conducting 16 different kinds of fire simulated evacuation scenarios,including the section of the peak time and training factors with full passenger loads. For this goal,we have chosen to take a passenger evacuation simulation software known as Pathfinder 2016（ the mode of steering is used as the Pathfinder＇s personnel movement patterns） into full effect. What is more,we have also managed to analyze a large number of subway transfer accidents due to the station evacuation bottlenecks. Based on the aftermath reports of the evacuation bottleneck accidents,we have improved the passenger evacuation routes and examined and confirmed the optimized results in the following ways： First of all,for the condition of the peak time traffic section,the optimal evacuation time tends to be a short period from within 17 s to 47 s,with the maximum optimization evacuation rate standing for14. 9%. But, for the condition of trains with full passenger loads,the maximum optimal time of fire scenarios from 7 s to 13 s should be 117 s with the maximum optimization rate being at about 21. 6%. The optimization time of Line 1 can likely be greater than that of Line 2. On the other hand,for the condition of the peak of the disaster moments,it would be possible for the evacuation path optimization layout to get rid effectively of the large scale crowd evacuation bottlenecks and reduce the evacuation time with the casualty liabilities controlled within the 6 min to meet the ＂6-min principle＂demands through optimization. But for the condition of full passenger load,though the total evacuation time can be reduced via the evacuation path optimization,it is likely for the evacuation time to go beyond the specific demands for such emergency transfer layout. Therefore,it would be desirable and necessary to focus the study on the fire safety prevention in case of the subway wagons with full passenger loads so as to get rid of more casualties.