Abstract: Aiming at the innovative architectural form of subway vehicle base with overhead comprehensive development project, this study investigates the smoke spread patterns and temperature distribution under a 1.5 MW test fire source in different functional areas (the inspection area and the throat area) of subway vehicle base through hot smoke tests. The experimental results show that: Under the natural smoke exhaust mode, the smoke generated in the fire scenarios of the train inspection area and the throat area can be effectively discharged through the natural smoke exhaust openings. The height of the smoke layer is always maintained above the safe clear height, and the visibility in the area near the fire source remains good without being significantly affected. This indicates that the natural smoke exhaust system of the metro vehicle base with overhead comprehensive development project in this study can effectively ensure fire safety. When the fire source is located in the throat area, smoke tends to spread to the depot side under the influence of environmental wind. It is recommended to install smoke barriers between the depot and the throat area to limit smoke diffusion and enhance the fire safety performance of the depot. Adopt a denser layout of smoke exhaust vents in elongated spaces to optimize smoke extraction efficiency. Prioritize the placement of smoke exhaust vents at the downstream position of prevailing wind direction to mitigate the adverse effects of environmental wind on exhaust performance.

Key words: subway vehicle base, natural smoke exhaust, hot smoke test, temperature distribution