Study On Fire Smoke Simulation And Staff Evacuation In Rail Transit Tunnel

In recent years,in order to alleviate the urban traffic pressure and keep up with the trend of the times,the construction of urban rail transit system is in full swing.However,due to the high closeness and limitation of the architectural space of the subway system,once there is a fire in the system,it will cause great casualties and property losses.So this paper takes the subway fire evacuation as the research object,aiming to provide some reference data for the evacuation form of subway fire accident,and to ensure the safety of passengers’ lives and properties to the greatest extent.Through searching and reading a large number of relevant literature,it is found that there are few articles in the existing research to explore whether the fire situation allows the train to arrive at the station for evacuation,most of which select the station as the evacuation location for simulation.This article takes Lanzhou Metro Line 1 as an example to study the circumstances under which trains are allowed to travel to the station and then evacuate passengers when the subway train travels in an intermittent tunnel fire.After that,when the train does not meet the conditions for evacuating passengers after running to the station,the train will stop in the interval tunnel to evacuate passengers.Later,when the train did not meet the conditions for evacuating passengers after arriving at the station,the train was forced to stop in the interval tunnel to evacuate passengers,the threat of smoke to passengers was then explored;Then explore how the smoke control can cooperate with the train to evacuate passengers in the interval tunnel,which can guarantee the safety of passengers to the greatest extent.Because there are no conditions for conducting physical experiments,this paper chooses to use computer software to simulate the experiment,establish a fire model and simulate the changes of smoke and temperature with time in the model,and divide the danger range.Then calculate and analyze the evacuation time of passengers on the subway train by hand algorithm,and judge whether the evacuation process is safe by comparing with the smoke and temperature in the model.Afterwards,the safest flue gas control measures were found through cyclic simulation,and the final research results were obtained.Through research,it is found that in the Lanzhou Metro Line 1,when a subway train with 70% of the passenger load has a fire in the interval tunnel,if the train cannot guarantee to drive to the station within 100 s,it cannot guarantee the safety after arrival To evacuate all passengers,they should immediately stop at the nearest contact channel to evacuate passengers after a fire is detected.The best parking evacuation location is within 130 m before and after the contact channel.For passenger evacuation,a fire in the middle of the train is the most dangerous because the fire source divides the passengers into two parts and some of the passengers cannot be evacuated using the communication channel.When the train on fire inthe middle is forced to stop in the evacuation of the section tunnel,the air shaft in the tunnel should be used to exhaust smoke immediately.When the exhaust wind speed is above 5m/s,the safety of the evacuation process can be ensured.After evacuation,longitudinal ventilation is performed in the section tunnel to ensure that another part of the passengers can stay away from the fire point against the wind,so as to ensure the safety of passengers.