沉管隧道火灾烟气蔓延特性  

Smoke spread characteristic in immersed tube tunnel fire

作　　者：徐湃[1] 蒋树屏[2] 周健[2] 陈大飞[2] 

机构地区：[1]重庆交通大学土木建筑学院,重庆400074 [2]招商局重庆交通科研设计院有限公司,重庆400067

出　　处：《长安大学学报（自然科学版）》2014年第6期125-130,共6页Journal of Chang’an University(Natural Science Edition)

基　　金：国家科技支撑计划项目(2011BAG07B05)

摘　　要：为了深入了解沉管隧道火灾过程中烟气的蔓延规律,通过理论推导与足尺试验验证相结合的方法,建立烟气流动的数学模型,推导出烟气层温度及流速沿隧道纵向衰减的理论模型。在此基础上,以港珠澳沉管隧道为研究对象,建立1∶1足尺沉管试验隧道,配备完善的机电系统与测量系统,开展隧道火灾试验,对不同火灾热释放速率和纵向风条件下的烟气层平均温度与平均流速的预测模型进行验证。研究结果表明:在忽略烟气层对下层冷空气的卷吸作用时,烟气温度沿隧道纵向呈指数衰减;同时,烟气蔓延速度的衰减与温度衰减成正比,沿隧道纵向也呈指数衰减。最终给出港珠澳大桥海底沉管隧道火灾工况下烟气运动的预测模型。This paper analyzed the fire smoke spread in immersed tube tunnel, established smoke move- ment control equation, and derived the theoretical model for predicting the smoke layer temperature and velocity decay in the longitudinal direction in tunnel fires. On this basis, taking Hongkong-Zhuhai-Macao immersed tube tunnel as the research subject, this paper carried out full-scale tunnel fire test, verified the forecasting model of mean temperature and mean spread speed of smoke layer under the condition of dif- ferent heat release rate and longitudinal wind. The results show that when the entrainment effect of the smoke layer on ambient air is ignored, an exponential decay model of the smoke layer temperature and velocity can be found; meanwhile, the smoke velocity varies with the change of smoke temperature. Fi- nally, the smoke movement prediction model of Hongkong-Zhuhai-Macao immersed tube tunnel fire is proposed. 6 tabs, 4 figs, 16 refs.

关 键 词：隧道工程 沉管隧道火灾 足尺试验 烟气层平均温度 烟气蔓延速度 

分 类 号：U459.2[建筑科学—桥梁与隧道工程]