Citation

Dong S, Zhang X, Wang K. Sustainability (Basel) 2022; 14(14): e8695.

Copyright

(Copyright © 2022, MDPI: Multidisciplinary Digital Publishing Institute)

DOI

10.3390/su14148695

PMID

unavailable

Abstract

During the actual operation of a subway company, only one ventilation-control scheme is considered in the emergency plan, without considering the specific location difference of the fire source. However, in the case of an actual tunnel fire, the best ventilation-control scheme and personnel-evacuation scheme are very different given the potential different locations of the fire source. We consider the use of a connecting channel for smoke exhaust or personnel evacuation and study the best ventilation-control scheme and personnel-evacuation scheme, when the fire source is at different positions relative to the train, and the train is at different positions relative to the connecting channel. Taking the tunnel between Yaojia Station and Nanguanling Station of Metro Line 1 in Dalian, China, as an example, a 1:1 full-scale numerical model is established to study dangerous fire-related conditions, such as carbon monoxide concentration, smoke visibility, and temperature. Nine typical working conditions of a tunnel-section fire are studied. The traditional and commonly used longitudinal-ventilation mode can ensure smoke control and personnel evacuation. For the working conditions of fire in the end of the train the ventilation-control scheme designed in this paper can ensure the safety of personnel. However, the working conditions of fire in the middle of a train are the most dangerous, and about 50% of personnel are affected by smoke during the escape. This paper analyzes the impact of the longitudinal-ventilation mode, transverse-ventilation mode, and semi-transverse-ventilation mode on personnel evacuation under such working conditions. It is found that with the semi-transverse-ventilation mode, personnel are least affected. Furthermore, semi-transverse ventilation requires a higher engineering investment, which is more than RMB 2000 per meter of tunnel. If the economic conditions are available, it is recommended to consider the semi-transverse-ventilation mode instead of the longitudinal-ventilation mode. The research results can provide guidance for the emergency-control scheme for subway-tunnel fire operation.

Language: en

Keywords

backlayering; connecting channel; location of fire source; location of smoke exhaust outlet; longitudinal wind speed; smoke exhaust mode; subway fire