Studies On Performance-based Fire Safety Egress Design In A Large Underground Emporium

Safety egress analysis and design is an important part of fire protection analysis and design of buildings; emporium fires have been gloomy at the moment; 21st century is to be an underground-space century. For all these reasons, underground emporiums are selected as the subject of this paper, which will be meaningful to the performance-based fire protection design in large public buildings. A mode of human behaviors in large public building fires is built up in the paper. Full-scale experiments in an underground thin and flat building with large space have been made. The results show that natural ventilation far from the fire and mechanical exhaust near to the fire is proposed in a large underground emporium. The hang ceiling not only makes the smoke temperature rise under the same power, but also impairs the smoke-accumulation ability of the top and accelerates the smoke movement, but it contributes to extract smoke, so hollowed-out ceiling is agreeable for a large underground emporium. Because smoke moves quickly through the atrium, the atrium should be separated from the storeys conjoint at least from the first floor as soon as fire breaks out; and the atrium local exhaust system starts. On the basis of full-scale practical fire experiments, performance-based fire safety egress design is applied to the case of East Station Underground Emporium. CFAST has been used to calculate the smoke movement, and the safety egress of the whole people, the subarea people and the peple in different fire departments have been simulated and analysed by the means of EVACNET4, Togawa and so on. The two results are then comparied, and improved ideas of deepening the sinking square and building up safety-islands are presented for the design. Finally fire protection countermeasures feasible to a large underground emporium are advanced. Through that a performance-based fire safety egress design project which is easy to operation is shown.