Investigation on the Effect of Platform Height on Smoke Characteristics of Fire Scenarios for Subway Stations

Desheng Xu,Jiaxin Li,Jin Zhang,Yanfeng Li,Junmei Li

doi:10.3390/su131910584

Abstract

In this study, three full-scale experiments and a series of numerical simulations were conducted to investigate the influence of subway platform height and atrium ceiling height of subway stations on smoke control by mechanical exhausting systems. The smoke temperature variation with time, maximum temperature distribution, and smoke stratification were discussed. Results showed that the atrium had capacity to store smoke, especially at the early stage of smoke spread. However, the efficiency of smoke extraction did not increase simply with the rise in platform height and atrium ceiling height, and favorable smoke exhaust velocity was crucial for smoke elimination. The optimal smoke exhaust velocity was studied by numerical simulation and it was found that the area of smoke diffusion in subway stations with a higher platform was significantly smaller under the optimal smoke exhaust velocity. In addition, a prediction model of optimal smoke exhaust velocity with subway platform height was proposed. This study could provide on-site data and smoke spread characteristics for smoke control design, operation, and, significantly, guide safety evacuation of the exhaust system of subway stations.

Highlights

As a significant means of transportation in the modern city, the subway system has been developed rapidly due to the advantages of large transportation, high velocity, punctuality, and low energy consumption
The exhaust velocity at 0.3 m height under the ceiling was researched for non-atrium subway stations
It can be considered that the ventilation and smoke exhaust system was more effective with small temperature rise in subway station fires

Summary

Introduction

As a significant means of transportation in the modern city, the subway system has been developed rapidly due to the advantages of large transportation, high velocity, punctuality, and low energy consumption. Due to the closed environment of the underground space and consistently high pedestrian flow, one of the key issues for subway security are fire accidents that could lead to overwhelming injuries and casualties [1,2,3]. In Baku, Azerbaijan’s capital, a large fire occurred in the subway station and there were 289 people killed and 265 people injured [6]. Studies on smoke control could help reduce casualties and property loss, and provide guidance for evacuation of people once fire occurs

Methods

Results

Conclusion