Design Optimization Of Smoke Control And Emergency Evacuation Based On Qingdao Overlapping Group Tunnel Subway Station

In the past decade or two,the subway construction projects in China’s major cities have been catching up with and surpassing the construction process of western developed countries in more than 100 years,with the construction speed and scale ranking first in the world.Subway project is an underground building with complex structure,relatively small and closed space,and also equipped with acousto-optic system equipment.In addition,the subway station has a relatively large population density.Once there is a fire,the station will inevitably be crowded seriously,and the evacuation is very difficult.In addition,the toxic and high-temperature gas produced by the fire also brings obstacles to the escape of people,even to people The threat to the lives of the staff.At present,most of the domestic subway stations are standard stations,which have similar building structure,plane layout and size,so the smoke control design and fire evacuation design of most domestic stations are similar.However,due to the geological structure,transfer mode,residential layout and other factors,there will be some special stations in the subway construction of each city.The smoke control design and emergency evacuation design of these non-standard stations need to be calculated and studied separately.In China,there is little comprehensive consideration for smoke control and fire evacuation design of non-standard stations with special structure.Most of them only consider a single specialty,but do not consider the multi specialty problems such as fire smoke flow,evacuation path,evacuation behavior and special station structure as a whole.There is a lack of overall in-depth analysis.When the basic conditions change,the smoke control and fire evacuation design is also corresponding Therefore,it is necessary to carry out the design of building evacuation and smoke control,so as to prevent the large losses caused by the simple general fire response scheme can not respond to the fire rescue timely and effectively after the fire.According to the structure type and individual layout of non-standard station,the design of building evacuation and smoke control is of great significance to extend the safe evacuation time and create a safe riding environment.This paper focuses on the smoke control design and emergency evacuation design of a special type of subway station with overlapping group holes in non-standard stations.Through the smoke flow law,passenger evacuation mode and path of such stations in the fire scene as the research object,various means and methods are used in the investigation and research process,especially combined with the fire dynamic theory and smoke flow characteristics Based on the analysis of the coupling research of the characteristics,the average temperature of the smoke layer and the evaluation standard of smoke control and exhaust,this paper takes Qingdao Metro overlapping group tunnel subway station as an example to carry out the research.1.Firstly,according to the organization form of passenger flow,the properties of electromechanical decoration equipment and materials,the properties of train body and the combustion characteristics of civil construction materials,the theoretical basis of fire causes and heat,toxic substances and visibility are analyzed,so as to determine the pre simulation parameters of station,such as fire source condition parameters,scene parameters and boundary conditions The physical model of the station is established by the disaster simulation software,and the smoke flow and spread law of the subway station fire are calculated and simulated,as well as the variation trend of smoke temperature,visibility and CO concentration of the station hall platform under different fire scenarios.The available safe evacuation time for people to achieve safe escape under different scenarios is summarized through the simulation results;2.According to the simulation results of fire scene and smoke spread at key monitoring points by pyrosim fire simulation software,this paper uses the evacuation software Pathfinder to simulate the evacuation situation of station platform stairway fire and train central fire at the peak passenger flow,and obtains the different situations of all personnel in the peak passenger flow situation Through the simulation results,the necessary evacuation time of station to achieve the safe evacuation of passengers is summarized;3.Comparing the available safety time obtained by pyrosim fire simulation software with the necessary evacuation time obtained by Pathfinder evacuation software,it can be concluded that the necessary evacuation time on each evacuation path is less than the available evacuation time,which can ensure that passengers can complete the safe evacuation.However,at the most disadvantageous point,the evacuation time is more than 600 s,which can not meet the minimum evacuation time of 360 s required by the code.Therefore,it is necessary to optimize the local smoke control design,fire linkage mode or building evacuation design,so as to meet the minimum evacuation time required by the code.4.This conclusion puts forward reasonable suggestions for smoke control design scheme,building evacuation design scheme and fire linkage mode improvement of Qingdao overlapping group tunnel subway station,and provides reference for smoke control design and fire evacuation design of the same type subway station.