The Study On Smoke Transportation And Personnel Evacuation In Multi-staircase Construction Fire

Building fire has the characteristics of rapid spread of fire,difficult to be extinguished,and can cause serious casualties and property losses.Most of the evacuation route in modern buildings,including residential buildings,public buildings,industrial buildings,agricultural buildings is the staircase.and the staircase is the only way for people to escape.In the event of a fire in a building with a staircase as the main evacuation channel,it is difficult for the personnel to escape to a safe position in a short period of time,and during the escape process,due to the spread of the fire smoke,the decline in visibility,High,toxic and harmful gas diffusion and other harsh environments,as well as changes in psychological behavior and other factors,there will be some stampede,jumping events,which also increase the difficulty of evacuation.Therefore,the study of the spread of fire smoke in the staircase and the evacuation of personnel,to understand the process of fire,reduce fire hazards,reduce casualties and property losses and other aspects have avery important research value.This paper mainly studies the object is the staircase as the main evacuation channel of such buildings.Through the field survey and study,to a university more than one staircase office building as a prototype,the establishment of a three staircase building model.Through the simulation of fire smoke and the simulation of evacuation,the paper summarizes the spread of fire smoke and the safety of evacuation of personnel in multi-staircase building.The following is the main content and conclusions:（1）Choose a college the stairs office building as the prototype,using FDS software to establish the model.Four different fire conditions were designed.By running the 3DSmokeview flue gas dynamic effect map,observe the direction of the flue gas path,speed,etc.,combined with the slice effect map to further analyze the spread of flue gas.Finally,the numerical simulation analysis is carried out from the three aspects of temperature,visibility and CO volume fraction.Draw the dangerous threshold of each floor.And the relevant conclusions are as follows: after the fire,no matter where the fire is located,the flue gas is the first direction toward the vents spread,fire smoke spread in the staircase at the same time,also to the corridor on both sides of the migration;Threatening personnel in addition to high temperature flue gas,as well as toxic and harmful gases,such as CO,CO₂,etc,while reducing thevisibility,that is,black smoke is also very dangerous.（2）The evacuation model is established by using the software Pathfinder.Set the number of people,set the parameters of personnel,set the security door,etc.,on the four kinds of fire conditions evacuation test.By the time of the evacuation of staff from different chart analysis,the conclusion that the number of evacuation.Research and analysis: fire conditions four the minimum risk,followed by the fire condition of two,the fire condition of three,the most dangerous is the fire conditions of one.Conclusion: the fire on the lower floor is more dangerous,and the fire is more dangerous near the outlet.No matter what kind of evacuation under the conditions of the building,the building cannot ensure that all personnel evacuated,so there are security risks in building.In this paper,the relevant improvements are given in the aspects of personnel safety training and building fire protection measures.