Abstract:Tunnel fire becomes a hot issue,and the problem how to consider the future fire probability during the design of the tunnel is needed to consider. The fire-proof section has to be planned according to staff escape speed,but also depending on the essential time of escape. Three important factors of tunnel fire,i.e. the temperature,concentration of carbon monoxide(CO) and visibility,which will threaten people¢s lives seriously,are analysed. It is a key of evacuation route design to make people escape from dangerous area safely in a certain time. So the time when temperature,visibility and consistency of carbon monoxide in tunnel menace people¢s lives is also studied. From this point of view,adopting computational fluent dynamics software FDS and evacuation model Tunev(tunnel evacuation),the available safety egress time(ASET)and required safety egress time(RSET) with the example of Shanghai river-crossing road tunnel are simulated. Then,the preliminary sketch of the distance of the tunnel evacuation section and the capacity of the escaping staircase are also presented. Finally,the fire-proof section is designed,which may provide some references to the escape-rescue design of tunnels.