Study Of The Fire-protection Design For Underground Buildings Based On BIM

Urban Rail Transit has a transmission capacity, low pollution, low energy consumption, punctual, reliable, convenient and so on, play an extremely important role in the public transport system in large and medium cities. However, the subway interior space is relatively closed, the narrow channel, a large concentration of people, so there is a prominent security risk. Once appearing in the station, the fire easily and quickly expanded with the flue gas easy to accumulate and to spread around, which most likely caused huge economic losses and casualties. Since the fire protection system is a key in subway fire control system, while its operating mode is very complex. Thus, in addition to the standard design in accordance with certain subway station fire protection system, also you need to make further study of the problem of performance design on the basis of mastering the subway fire behavior.Currently, the main method to research subway fire include:full scale test, reduced scale tests and numerical calculations. Paper takes the project of Beijing Municipal Science and Technology Commission that "deep subway station fire design, simulation and applications" as the basis, selects a Subway Station in Beijing and its exhaust ventilation system for the object, bases on BIM (Building Information Modeling) concept established fairly close to the actual model, combines with the subway station measured data, and uses computational fluid dynamics (CFD) software and simulation software Pathfinder to study subway fire, smoke ventilation function and evacuation issues via numerical simulation and analysis.The main contents of the paper include:First, the analysis the influence of the piston effect of the wind and the subway station platform safety doors on fire smoke ventilation and smoke effects during the train pit stop; Second, the analysis of different positions in the train fire, fire station and other conditions, the space station’s flow field, temperature field, gas diffusion law, and checkout the smoke control system meets the requirement of "Metro design specifications"; Third, the analysis of fire personnel safe evacuation law within the station when the different scenarios, inspect the evacuation conditions are meet regulatory requirements.Through the research, the paper proposes and practice using BIM information model fluid flow simulation and evacuation simulation method. We get the subway station fire smoke, flue gas temperature distribution and influence of airflow due to the piston effect of wind and security doors. Preliminary master the station evacuated laws under the various scenes. At the same time, pointing out the design shortcomings of the existing anti-ventilation system, and analyzes the improvement measures. And put forward some suggestions to the subway fire emergency plan.