Coupling evacuation model of air-supported membrane buildings subjected to air-leakage based on multi-velocity cellular automaton

Air-supported membrane buildings may suffer from air-leakage caused by the opening of exit, failure of inflation system or environmental force majeure, which is essential for pedestrians' evacuation but receives less attention. The paper proposes a coupling evacuation model based on multi-velocity cellular automaton by incorporating dynamic air-leakage process in evacuation analysis to quantitatively assess the impact of air-leakage on evacuation. Two factors are considered to determine evacuation process in deflating building- herding behavior caused by panic among crowd and the variation of moving velocity. An experiment was conducted to obtain individual velocity under different elevations of membrane surface to provide practical velocity for the model. Coupling simulation results show that evacuation efficiency can be raised in the deflating building with small population density, which is reduced as population density grows. The maximum capacity of the double-exit building is improved by 24% of the single-exit building. This work offers a possible method to predict crowd movement process and assess the level of security of air-supported membrane buildings suffered air-leakage under emergency from the aspect of evacuation dynamics.