The Fire Growth And Spreading Characteristic Research Of Unfixed Fire Loads In Large Space Buildings

Fire growth and spreading characteristic has long been recognized an important role in architecture fire safety research. Based on the analyses of fire cases in large space buildings, the fire growth and spreading characteristic of unfixed fire loads in large space building research works have been carried out. The research is a new approach to fire safety engineering. It's useful to the fire risk evaluation, performance-based design and fire model, and so on. In order to study the influence degree of different placement fashion about the fire risk evaluation of combustible materials in theory, establishing three style of numerical model of horizontal flame spreading, upward flame spreading along the wall and upward flame spreading along both sides. The results of flame spreading test of combustible materials show the placement fashion is the most important factor which determine the risk degree of fire. Under the same placement fashion ,different material obey to the same heat transfer principium. The heat transfer principium will influence the flame spreading velocity at last. Based on the numerical model and testing data, the nonlinear regression summary statistics dependent variable work has been done, and got three style of summary statistics formulas for three style flame spreading fashion. The main influence factors of Uf are Tf, Hf, , and property of material. The formulas can be used to forecast the flame spreading velocity of different materials under some style of flame spreading fashion. According to the research work of heat release rate(HRR) of thin type material under different placement fashion, the HRR is determined by the following main factors, such as the placement fashion, the size of outline, the category and combustion properties , catching fire point position and the environment situation. One kind of material has different HRR at different condition. So ,it's not reasonable to evaluate the fire risk with the same guideline. The research is useful to extend the research range of fire. Through the investigating of unfixed fire loads of clothes floors in emporium on the spot, the result show there are different area density in different floors, and different portion distributing density in one floor. The distributing condition reflects the real distribution of unfixed fire loads. The statistics result is that the distributing of unfixed fire loads obey the binomial distribution, but not the normal distribution. Through studying the flame spreading characteristic of the fuel which be placed inone rack and in adjacent racks in the full-scale and small-scale testing equipments, the results show the flame spreading characteristic is spreading fire source. The boundary shape and length of fire zone are growth with time, which determine the fire HRR is variational with time and space distribution. The fire HRR is different from the steady fire and T square fire. Through founding the fire spreading model of continuous distributing laminal fuel ,it can be used to forecast the fire parameter when fire spreading in some kind of construction area and provide a new fire design method for fire modeling...