Research On Fir-fighting Measures Of Large-scale Basement Parking Garage

With the development of social economy, the car has gradually enter into the ordinary families,the Number of cars in China has been increasing year by year.The problem that parking space become nervous is becoming more and more serious, especially in large cities, it is difficult to find a parking space.In the process of the development of the city, the development of underground space become more and more, and building large underground garage can be a good way to solve the problem of parking space nervous, but at the same time,this way will bring the underground garage fire safety problems,the reality shows that only fully design the underground garage fire control measures can effectively reduce the number of fire, reduce the loss of fire, and ensure people's property and life safety.At present, for extinguishing facilities of underground garage fire, the domestic and overseas design.Mostly choose traditional automatic sprinkler system, for the fire which is caused by solid material, automatic sprinkler system can effectively restrain the development of early fire and won the time for extinguishing fire, but more and more facts show that traditional automatic sprinkler system have no obvious effect to the underground garage fire which is caused by class B (liquid). Because the bubble liquid can effectively put out the class B fire. By introducing the bubble liquid, the automatic water spray system will become a new type of fire fighting facilities: automatic water spray——foam system. In this paper, the principle of the fire fighting system were analyzed, and the results will be used in the design of underground garage fire.First of all, the paper analysis the spread model of the underground garage fire by using the fire model——"Q=at2", which is used widely, this model is used to simulate the developmental process of fast fire and super fast fire. Due to the underground garage fire type is complex, there are mainly2types:A class fire and B class fire, because the cause of the fire is different and the car fire site is different, these will affects arrival of fire's biggest heat release rate. The author thinks that according to the most unfavorable conditions into consideration, namely fire caused by leakage of Mailbox oil. The speed of Liquid (fuel) fire development is faster,the maximum heat release rate is soon reached, at the same time, the time of Igniting solid fuels is short, so as value of the model could choose the sum of fast fire and super fast fire, namely a=0.23469kW/s2Secondly, this paper studies domestic and overseas facilities which is applied in underground garage fire fighting:fire-hydrant system, automatic water spray system, automatic spraying foam system, High multiples foam system and so on, the paper Compares these facilities's applicability which use in underground garage fire.This article mainly contrast automatic water spray system and automatic water spray——foam system's principle as well as to the effect of heat release rate.The paper argues that By introducing the bubble liquid, the automatic water spray system becomes automatic water spray——foam system.usually we choose6%water film liquid foam (AFFF) to save underground garage fire, with the foam exhalation liquid can forme covering layer on the surface of the oil film, plus foam itself coverage.the double cover effective Separate the contact of the fuel and air and block the burning.It has obvious effect for saving for class B fire. At the same time, this paper puts forward specific design scheme which is application of the automatic water spray——foam system in Large underground garage.This paper analyses the problems which should be paid attention to In the design.The article puts forward the design scheme could be reference,which contrapose the specification's shortcoming and indistinction.