Research On Fire Safety Evacuation In A Large Commercial Emporium

With the development of economy and the improvement of national living standard, a number of large-scale emporiums have been built these years. However, the fire of these emporiums often results in heavy casualties. Personnel evacuation in a fire accident is the most important content of fire control design of a large-scale emporium. According to the fire risk and characteristics of large emporiums, the paper carries out theoretical and experimental research on personnel’s safety evacuation, which will provides basis for the performance-based design of safety evacuation in large-scale emporium fire. It plays essential and practical roles on compiling the code for design of fire protection in buildings.By taking the personnel evacuation experiment in a large-scale emporium, the paper uses questionnaire, empirical formula and computer simulation methods for systematic analysis, focusing on the route choices of researchers’ evacuation,the time of fire evacuation, the relationship between the action of personnel evacuation and their characteristics.Combined with internal common structure form in a large-scale emporium, full-scale experiments in the commercial streets, the atriums and the flat large business halls have been made respectively. The results show that the self-developing smoke filling process model has good applicability. It also shows that natural ventilation far from the fire and mechanical exhaust near to the fire are suitable ways in a large- scale emporium. However it is better to open the fan 1 to 2 minutes later than to open the fan immediately when the fire breaks out. The rising of smoke temperature in the commercial streets and business halls is higher than that in the atriums in case of fire. The flue gas temperature distribution in vertical direction rises with the increase of the height from ground. After installing the hang ceiling, the smoke temperature rises under the same power. And the law is more regular than no ceiling. Furthermore, the hang ceiling contributes to reduce the resistance of the flue gas flowing to the exhaust port in the mechanical smoke extraction, though it impairs the smoke-accumulation ability of the top and accelerates the smoke movement. Therefore, hollowed-out ceiling is suitable for a large-scale emporium. Because smoke moves quickly through the atrium, the atrium should be separated from the storeys connected with the surrounding floors, at least, with the top floor as soon as the fire breaks out, and the local smoke control system of atrium is also adopted for smoke evacuation. In the case of business halls fire, it should be separated from the connection between the atrium and the surrounding floors, at least, the top and the fire floor. Meanwhile, it should use the local smoke control system in the fire floor for smoke evacuation. With the natural beam division of smoke partitions, exhaust ports must be set up in smoke storage zones.After analyzing the influence factors of personnel evacuation, the characteristics of fire and features of the buildings, the paper further points out that the security channel, "Backward evacuation" and the other improved building characteristics methods can improve fire safety evacuation performance.On the basis of full-scale practical fire experiments, performance-based fire safety egress design is applied to the Commercial Square of East Station. CFAST and FDS has been used to calculate the smoke movement, and the safety egress of the whole, the subarea and all the fire zone personnel have been simulated and analysed by the means of EVACNET4, Togawa and so on. The two results are then compared, and improved ideas are presented for the design.Based on the fuzzy analytic hierarchy process(AHP),a large-scale emporium fire evacuation assessment model is established, which has been proven to be scientific and effective by its application examples. The model can be applied to various emporiums of different structure forms, and can provide the basis for standardization of fire safety management rating in city mall industry.