A Study Of Evacuation Strategies In High-Rise Buildings

High-rise buildings develop rapidly with the progress of science and technology. At present，there arehundreds of high-rise buildings in China, and the number is increasing. Because of the complex and hugestructure， high-rise buildings are easy to cause major disaster once in the event of fire. Currently, it isstill difficult to conduct fire-fighting and rescuing timely and effectively for high-rise buildings, people’ssafety in this kind of fire relys mainly on early evacuation. Because of many evacuees and long distance inhigh-rise buildings evacuation，and with the development of fire，smoke may also block exit channels,thus the evacuation time often needs several hours, so there are significant threat to personnel. How toreduce the time in high-rise building fire evacuation becomes a problem to be solved as soon as possible.Basing on the analysis of the structure characteristics of high-rise buildings，this paper dissects thecharacteristics of high-rise buildings fire and the main factors influencing the evacuation. Considering theenvironmental factors in fire, and basing on the fire simulation software FDS, this paper analyzes thesmoke spreading in different fire floor of high-rise buildings. Combining quantitative and qualitativemethods, danger zone, relative safety zone and safety zone are defined in the high-rise buildings fire.According to the characters of structure and fire characteristics of high-rise buildings, an improvingevacuation strategy is put forward on the basis of the traditional evacuation strategy. On the one hand, thetotal evacuation, phased evacuation, delayed evacuation and defend-in-place strategy are combined andoptimized, on the other hand，the evacuation mode is also optimized. It turns out that the evacuationcombining stairs and elevators is superior based on the results Pathfinder evacuation simulation software.The relationship between the elevator number distribution and refuge storey’s height is analyzed, thus theevacuation strategy is optimized if combining the elevators and stairs.