深埋岛式高铁车站站台火灾烟气蔓延特性及防控研究

Smoke Movement and Control of Island High-speed Railway Underground Station Platform Fire

高铁地下车站结构复杂、功能多样。其站台区域埋深较大,是长宽比较大的狭长受限空间,一旦发生火灾,危害巨大。统计表明,有毒有害的烟气是火灾中最主要的致死因素,而狭长受限空间的结构特点和通风条件决定,其火灾产生的烟气难以立即排出,因此,高铁地下车站站台火灾烟气的蔓延特性是值得关注的问题。其中,火灾烟气的蔓延规律与防控是与消防安全设计密切相关的科学问题。以某双岛六线式高铁地下车站为研究对象,围绕站台狭长空间火灾的通风排烟模式和排烟参数,开展三维数值研究。其中,主要分析火灾发展过程中的烟气温度、碳烟密度、扶梯通道风速等特征参数的分布情况。研究结果表明:站台火灾采取单独的站台排烟系统可以合理的排出烟气,若采取站台风机与隧道风机的合理匹配运行模式还可以使得扶梯通道稳定形成超过1.5m/s的下行风速。所提出的排烟模式和排烟参数适用于该类型车站的火灾防排烟设计。

Complex structure and diverse functions are the characteristics of high-speed rail underground stations. The platform area is often located in deep underground. A fire that occurs in a confined space with a relatively large length and width can be defined as a passage fire. We dread to think what would happen if there really was a fire here. Statistics have shown that the toxic fire smoke is the most hazardous factor in a fire. Due to the characteristic of structure and that of ventilation condition.It is difficult to exhaust fire smoke out of a channel immediately. Therefore,the characteristics of smoke transport in a high-speed rail underground station platform should be concerned. The spread law and control of fire smoke are closely related to fire safety design.This paper takes an island-style underground station as the research object, and uses numerical simulation to study the smoke exhaust mode and exhaust parameters of the fire in the narrow space of the platform. It mainly analyzes the distribution of characteristic parameters such as smoke temperature, soot density, and wind speed of escalator passages during the development of a fire. The results show that the smoke exhaust of the platform fire needs to adopt the reasonable matching operation mode between the station and the tunnel fan to make the wind speed of the stairs reach the speed requirements of 1.5 m/s, and that the proposed smoke exhaust mode and parameters are applicable to the fire smoke prevention and exhaust design of this type of station.