Search And Rescue For Occupants In Metro Stations Under Low Visibility After A Catastrophe

With the acceleration of urbanization,the problem of urban traffic congestion has attracted increasing attention.As a safe,reliable and high-volume public transport,urban rail transit become the main form of urban public transport.The expanding network scale and increasing passenger flow incur more accidents in urban rail transit systems.Once a public safety accident occurs,the limited space and dense passenger flow will complicate the evacuation and rescue.Especially in the event of fire and other disasters,it will certainly bring serious threats to the safety of life and property of passengers without prepared rescue schedule.At present,there have been extensive and in-depth studies on the emergency evacuation of subway stations,but few of them studies on the follow-up search and rescue work.Therefore,it is necessary to conduct the study on the post-disaster rescue work of subway stations to further reduce the losses during disasters.In most subway stations,the space is relatively limited and the natural light is lacking.After the fire occurrence,the smoke diffused rapidly which rapidly decrease the visibility and cause difficulty for the rescue work.The trapped people can endure very limited time because of the hostile environment,so the rescue work needs to be carried out promptly;at the same time,the arriving of the rescue force may not be fast since the distance from rescue station is different.It is difficult to execute the sweeping search because of the larger space such as the platform and station hall.Without a reasonable division of the search area of each player,the entire rescue process may need to take a long time,which is dangerous for the trapped people and rescuers in light of the above problem,the division of station search area and rescue strategy are studied in this paper.The main research contents are listed as follows:(1)The search method and its applicable conditions under low visibility conditions are analyzed,analyze the factors affecting the search efficiency is evaluated,whose relevant parameters in the search process are determined through geometric and experimental methods.The corresponding simulation platform is established.The research shows that the change of search position has a significant impact on the search efficiency.And it's important to improve the environmental situation of the scene as far as possible in the search and rescue process.(2)Due to the large area of platform and station hall in subway station,multiple people are often required to search the relevant area at the same time in the process of personnel search.Therefore,the method of search area division is studied for an optimized arrangement of search area for each rescue team member in order to a high-level overall efficiency.(3)Different rescue strategies are proposed based on the analysis on the tasks of the first rescue forces.A simulation platform is established for comparing the results of various rescue strategies under the cense of fire accident.The rescue strategy is evaluated for the optimal strategy after the accident.The research shows that to grasp the information of all the trapped people as soon as possible is of positive significance to improve the rescue efficiency.