DOI RECORD
Dynamic spatio-temporal framework for hierarchical fire hazard assessment during evacuation: Validation with metro tunnel fire
Abstract
Fire hazard assessment for metro train fires in tunnels remains challenging because existing approaches often evaluate fire evolution and occupant evacuation separately and lack comprehensive metrics for characterizing the spatial and scenario-dependent variations of fire hazards. To address this, this study proposes a dynamic spatio-temporal fire hazard assessment approach by integrating transient thermal environments with occupant evacuation trajectories, in which trajectory-based Fractional Effective Dose (FED) calculations and hierarchical hazard indicators were developed to quantify fire hazards at the individual, regional, and scenario levels. Validation of the proposed approach was achieved by coupling transient thermal data from the 1:5 reduced-scale train–tunnel experiment with time-stamped occupant trajectories from evacuation simulations. Results demonstrate that temperature within the train decay more rapidly than conventional tunnel fires due to side-opening smoke spill and gangway flow disturbances. Occupant thermal exposure is mainly accumulated during evacuation from the fire carriage, while platform-level hazards remain limited. Fire location and occupant density dominate overall exposure, with end-car fires producing the highest risk and yielding peak instantaneous and cumulative exposures 2.95 and 2.66 times those of mid-car fires, respectively.