疏散路径受阻情况下的人员疏散模型及算法

建筑火灾中,随着火势的不断增大和烟气的不断增多,随时会有某条疏散路径因被火势或烟气封堵而不能正常通行的情况发生。针对此情况下的应急疏散问题,以待疏散人员全部完成疏散所需时间最短为目标,以结合疏散路径的通行能力合理分配待疏散人员为原则,运用Dijkstra算法对网络中的最短路径进行求解,并结合网络流控制的方法实现疏散人员的合理分配,建立了疏散路径受阻情况下的人员疏散模型,并提出了该模型的算法思想及算法步骤,最后结合算例进行了验证。验证结果表明,该模型及算法可行、有效,既可较好地避免因大量人员选择相同疏散路线而造成的拥堵,还提高了疏散网络的整体使用率,又有效缩短了人员的疏散所需时间。

Evacuation model and the algorithm on the condition of the urgent obstructed evacuation route

The objective of this paper is to devote itself to the study on how to shorten the evacuation time to the minimalized degree based on the principle for the rational distribution of the evacuees in combination with the capacity constraints of the evacuation routes.Needless to say,in case when a fire occurs,it turns to be natural for the evacuees to escape to the safety areas as quickly as possible to seek their life safety,which demands to work out a scientific and effective evacuation method or approach for the evacuating people to follow.Nevertheless,there often exist unfavorable factors to prevent the fire sufferers to take advantages of the very limited available evacuation routes,particularly due to the fire fast spread and smoke movement,which may create a general psychological panic.For this emergency evacuation problem,we would like to propose a reasonable consumption for the general public to pay attention to,first of all.Based on the study of the graph theory and its underlying principle,we have then established a model for evacuation and further improved on it in referring to the monophyletic emergency evacuation model with the help of the heuristic algorithm and network flow control theory.The evacuation model we have established has been founded on the condition that the evacuation routes are likely to be blocked out in a certain situation,for which we have also prepared corresponding algorithms and steps here.Finally,a case study sample has also been provided to verify the effect and validity of this evacuation model and the algorithm,which are expected to overcome the weaknesses of the traditional algorithm though not of real-time by nature.The results of the trial-and-fail tests show that the model and algorithm are feasible and effective,displaying its due practical value in actual application.What is more,this model and algorithm can help to evade congestion situations effectively even if large crowds of evacuees choose to escape through the same evacuation route.In addition,the sufficient usability of the evacuation route can be achieved and the entire evacuation time can be shortened to a great extent with the help of our model.Thus,it can be seen that the model we have proposed in this paper can be expected used to guide the evacuation process and behavior in the actual situation in urgent need.Needless to say,the model can be taken as a reference in a theoretic sense for the managers and decision makers in the fire prevention and fighting fields.