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In this paper, to study the influence of stack effect on fire in the compartment adjacent to a stairwell, a set of experiments were conducted by varying the pool size, top vent state and bottom vent size in a 1/3 scaled 12-layer-stairwell configuration. The phenomenon of methanol flame tilting in the fire room was observed and studied. Results showed that the flame tilt angle increases with an increase of Ri -1 . The temperatures of hot gases in the fire room decrease due to the cooling effect of fresh air induced by stack effect. The mass loss rate of methanol fuel is influenced by fresh air flow sucked into fire room due to stack effect. On the basis of the experimental results, we conclude that the velocity of air flow into fire room is proportional to 1/3 power of the heat release rate in the stairwell.Keywords: stack effect, high-rise buildings, fire behaviour, compartment fire. Reference to this paper should be made as follows: Shi, W. X.; Ji, J.; Sun, J. H.; Lo, S. M.; Li, L. J.; Yuan, X. Y. 2013. Experimental study on influence of stack effect on fire in the compartment adjacent to stairwell of high rise building, Journal of Civil Engineering and Management 20(1): 121-131. http://dx.

A small amount of literature has been produced on the study of panic spread in a large-scale emergency evacuation, especially that which involves rescue guidance. In a large-scale evacuation action, there are complicated interactions between people and the disaster environment, and it is very difficult to present such interactions in quantitative functions or specific values. In this paper, a qualitatively simulated approach to model and study the panic spread is proposed. First, the internal structure of the evacuation system is described and various internal and external phenomena related to the change of evacuees’ behaviors in the evacuation process are qualitatively interpreted. Based on the qualitative knowledge, a qualitative simulation model of a large-scale evacuation system is established. The calculation results of inverse group matrix verify the rationality and stability of our model. According to the implementation of a series of scenarios with different input, some uncertainty factors that can affect the panic spread in the evacuation process are analyzed, in which the spread of disaster, the rescue guidance, and the normal emotional evacuees are mainly considered. This model reproduces a well-known phenomenon in crowd evacuation, namely “fast is slow”, and confirms that the severity of disaster exponentially positively correlates with the panic spread, and the effectiveness of rescue guidance is influenced by the leading emotion in the crowds as a whole.

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