Strategy Of Fire Risk And Fire Control Design For Long And Large Railway Underwater Tunnels

With the rapid development of national economy and railway construction, more and more railway bridges and railway tunnels cross rivers and oceans. The underwater tunnel would not occupy the way of navigation and would not be influenced by natural weather, such as wind, thunder and rain and would not carry out bad impact on ecological environment. With the enhancement of construction technology, underwater tunnel become the priority choice of railway crossing great river, even strait.However, existing codes, such as'Code of Design on Building Fire Protection and Prevention','Code for Design of Metro','Code for Design of High speed Railway','Code for Design on Fire Prevention of Railway Engineering'and'Code for Design on Operating Ventilation of Railway Tunnel', definitely stated that thery are not suitable for underwater tunnel of railway. The fire saftety design of underwater tunnel is beyond the scope of current fire codes. At the same time, because the fire experimental study and theoretical analysis of railway underwater tunnel is still on the preliminary stage, fire protection design is lack of technical reference.Regarding to railway tunnel, especially long and large railway, the underwater tunnel is a chock point of railway transportation. Smoke exhaust, evacuation, rescuing will be difficult since it normally has long and sealed space. Once fire happened in tunnels, it usually could bring about huge loss of life and treausures. If the apparatus and structure of tunnel are destroyed, the railway transportation will have to be shut down for a long time which will cause wretched social impact.This paper take the long railway underwater tunnel as research object, analyzing the typical fire cases, potential fire source, distribution of fire load. On the other hand, personal feature, behavior characteristics and evacuation process in long and large railway underwater tunnel was investigated. Based on quantitative calculating critical wind velocity and personnel safety evacuation time in the tunnel, measures and emergency rescuing strategy have been put forward to enhance fire safety of long railway underwater tunnel. And this, accordingly, will be useful to be the technical reference for emergency settlement.