普通玻璃在明火源作用下的宏观破坏痕迹研究

Study on Cracking Features of Ordinary Glass in Open Flames

为研究普通玻璃在明火源作用下的破坏痕迹特征及其在火灾中的证明作用,利用灶台火、油盘火、酒精喷灯三种火源对试验玻璃施加受热作用,考察了玻璃厚度、玻璃受热方式对玻璃破坏痕迹的影响。结果发现,酒精喷灯火焰和灶台火使玻璃破裂痕迹呈现为受火中心向四周发散的痕迹,油盘火作用下的玻璃破裂痕迹为树枝状裂纹,裂纹少且分布均匀;玻璃厚度对其热炸裂的时间有影响,玻璃破裂时受火面中心温度随着玻璃厚度的增加而升高;玻璃在火源水平作用下不发生破裂。

In order to study the cracking features of ordinary glass in open flames and its role in fire investigation,an experiment was conducted with the test glass heated by three fire sources,including stove fire,oil pan fire and alcohol blast burner. The influence of the glass thickness,glass heating method on the glass damage traces was studied.The results show that the crack traces of the test glass heated by alcohol blast burner and stove fire run from the fire center to the surroundings. The rupture patterns of the test glass heated by oil pan fire are in dendritic shape with fewer cracks in homogeneous distribution. The thickness of the glass affects the time of its thermal rupture: when the glass ruptures,the center temperature of the heated surface increases with the augment of the glass thickness. The glass does not crack under the horizontal force of the fire source.