Influence of sealing ratio on ceiling temperature distribution of tunnel fire

doi:10.16265/j.cnki.issn1003-3033.2020.02.013

Abstract

Abstract: In order to understand temperature characteristics of fire field during sealing of tunnel fire, a 1:10 scale tunnel model was set up to explore temperature changes of tunnel ceiling and its attenuation mechanism with fire source power of 12.67, 18.24, and 24.83 kW and sealing ratios of 0%, 25%, 50%, at 75% and 100%. The experimental results show that 25% and 50% sealing ratios have little effect on temperature rise in tunnel while 75% and 100% sealing will cause a sudden increase in temperature. As sealing ratio increases, temperature decay will come in advance. Power of fire source only changes the maximum value of ceiling temperature with no impact on longitudinal distribution of temperature, and heating rate in center of fire source is high. Temperature longitudinal distribution on downwind side attenuates exponentially during sealing, and it shows a linear fitting relation between sealing ratio and fitting coefficient b and temperature attenuation coefficient k.

Key words: tunnel fire, sealing, ceiling temperature, longitudinal distribution of temperature, temperature attenuation

CLC Number:

X928.7

MA Li, LI Chaohua, ZHANG Pengyu, QIU Xianzong, ZHAO Xin. Influence of sealing ratio on ceiling temperature distribution of tunnel fire[J]. China Safety Science Journal, 2020, 30(2): 79-85.

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