Island Platform Station Subway Performance-based Fire Protection Design And Research

In the urban public transport, the underground railway is not only an importantsymbol of the development of the metropolis but also indicate the future of urbantransport. More and more countries in the world have already built or are building thesystem of subway while the domestic system of metro is also developing rapidly. Metrocan make trip convenient.However, it is limited in a lot of thorny problems such as fireprevention and control.In recent years fires break out in in the subway frequentlycausing heavy casualties and great loss of property.The subway construction is different from the building on the ground. It’s distinctcharacteristics including the amazing flow of the passengers and the less escape routescan be attributed to the long and narrow space which is explored in the ground andrelatively enclosed. By comparison with the performance-based fire safety design, thetraditional instruction design is unable to meet the design requirements gradually. As anew type of fire protection design, the performance-based fire safety design has thecompetitive advantages in flexibility, security, economy and scientificalness. Takingthe performance-based design objective of the structure overall into consideration, theperformance-based fire safety design based on the principle of fire safety engineeringgets the best fire protection design according to the qualitative, quantitative evaluationand prediction of the actual situation of the structure.In theory improving the modes of ventilation and smoke extraction in tube stationscan achieve the purposes of controling the smoke, reducing the temperature of the stairsand decreasing the thickness of the flue layer. In the actual projects, changes in thepatterns of ventilation and smoke extraction raise higher requirements for the technology of environmental control system. But blindly increasing the environmentalcontrol technology will rise the investment of equipment wastefully. Reducing theamount of shielding door open,changing stair openings and cutting down the number ofstairs is where this paper desires to to meet the fire design because it’s easy to realizewithout altering the traditional ventilation modes of subway platform.Appling the principle of performance-based fire protection design, the numerical simulation analysis of Stadium island platform station in Xi’an No.2subway was carriedout with the FDS (Fire Dynamics Simulator) software. We can operate FDS softwarehandling the rules of the smoke concentration and flow rule and the variation of thetemperature at security level (at eye height1.6m) at the foot of the stairs when fireoccour in the center of the platform, stairs and the interval track.Some suggestions are put forward according to the results of the numerical simulation,which are helpful to the subway ventilation and smoke exhaust design in the future.