Effectiveness of Evacuation in Downward Direction in a Subway Station Using Fire Dynamics Simulator

摘要

An effective evacuation in a subway station was studied in the case of a fire. Coincidence with directions of evacuation and smoke-flow toward the ground poses major problems to evacuees in subway stations. Therefore, the evacuation and the smokeflow routes should be divided each other. In this study, the Jungangno subway station with three basement (B3) levels in which a disastrous fire broke out in Daegu, South Korea in 2003 was used as a model station. Influences of smoke, temperature and carbon monoxide (CO) were investigated at evacuation staircases in the subway station set a fire source in B3 floor using Fire Dynamics Simulator. The results showed that smoke density, temperature, and CO concentration at all of staircases increased significantly because smoke flowed through these staircases. A new subway station having a fourth basement (B4) floor was prepared by adding downward evacuation staircases from the B3 floor to the B4 floor. The simulation for the new subway station showed that the smoke density, temperature, and CO concentration scarcely increased at these downward staircases to the B4 floor. This paper concluded that the evacuation in downward direction was more effective than that in upward direction in the subway fire.