Research On Fire Scenario And Safe Evacuation Of Chongming Crossing-river Tunnel

On the based of Chongming crossing-river highway tunnel, This paper researches the relevance and affecting factors of fire smoke spreading and people evacuation , and then analyzes the design justification of smoke preventation& extraction system and evacuation system of the tunnel. Finally, presents the basic strategies of fire prevention and rescue of the tunnel.Firstly, fire disater damage and losing degree of some long highway tunnels in the world is presented, and the characteristic of the long highway tunnel on fire, research situation of safe evacuation at home and abroad is introduced. Some calculation methods about evacuation time are given, including three-step evacuation time experiential formula calculation method in Japan (awareness time, travel time and queue time ), and two computational models which are Simulex and STEPS. Accordingly, analyzes the main factors of fire smoke spreading of Chongming tunnel by FLUENT software, including fire position, fire scale and mechanical smoke exhaust flux. Aimed at Chongming tunnel, factors of people safe evacuation, including fire detection, person response, courses of action are analyzed. Here mainly uses the STEPS evacuation software to analyze the influence factors of fire position, people density, people moving velocity and evacuation channel width on the course of action. According to the fire position, fire growth rate, maximum fire scale and exhaust measures, fire scenarios is chosen. Based on these scenarios, justification of smoke extraction system and evacuation system of Chongming tunnel is estimated. According to some basic prevention principles of long highway tunnel fire disaster, prevention and rescue measures of Chongming tunnel are proposed.Some content of this article not only provides scientific and rational methods for appraisement of fire safety to fire protection engineer, but also offers a reliable reference to design building and smoke control system.