Abstract：Six full-scale tunnel fire experiments were conducted in a tunnel at a high altitude of 4100m.Three difference size of the fuel pool (0.8m2, 1.0m2 and 2.0m2) were used as fire sources. The smoke spreading characteristics, maximum temperature and longitudinal temperature distribution were studied. The results show that the interface between the upper hot smoke layer and the lower cold air is clear at early and steady stage of the fire but fuzzy at the decay stage, and the low ventilation velocity can control the longitudinal and vertical movement of the back-layering well in a small tunnel fire. Moreover, the temperature rise rate increases with the heat release rate. The longitudinal ceiling temperature decays fast in the vicinity of the fire source within 20m and slow away from the fire. Besides, based on the analysis results of the smoke temperature above the fire source, it is found that the fire detection adopting the differential temperature alarm is more efficient than that adopting the constant temperature alarm and the temperature growth rate of 10℃/min can work well in a small tunnel fire. In addition, by studying the longitudinal temperature distribution and the thickness of the smoke layer, it can be obtained that the smoke layer descend at first in the place far away from the fire source while has a well stratification in vicinity of the fire. The characteristic of the temperature distribution of tunnel fires at high altitude can provide valuable data for the study on the fire dynamics of tunnel fire at high altitude and can offer guidance and suggestion for the human evacuation in case of a fire at high altitude.
郭庆华 闫治国 朱合华 . 高海拔隧道全尺寸火灾烟气及温度场特征试验研究[J]. 土木工程学报, 2017, 50(8): 114-120.
Guo Qinghua Yan Zhiguo Zhu Hehua. Full-scale experimental study on smoke and temperature distribution characteristics of the tunnel fire at high altitude. 土木工程学报, 2017, 50(8): 114-120.
