真实火灾下单层门式刚架抗倒塌性能试验研究

设计完成了一个单层单跨门式刚架厂房的足尺火灾试验，得到了主要构件的温度及位移发展规律，分析了真实火灾下门式刚架厂房结构的受力响应。结果显示：真实火灾下门式刚架的温升曲线与标准升温曲线有较大差别，燃烧室中的上部构件达到较高温度而提前失效，下部构件温度较低；在火灾下，未做防火保护的钢结构很短时间内就会发生垮塌，在火场及构件到达峰值温度前结构已产生较大位移。试验研究发现，受火柱的柱顶出现了热膨胀伸长、轴向压缩、轴向破坏三个阶段，且受顶部热烟气聚集的影响，各柱的柱顶轴向位移均大于柱中位移。试验成果可为门式刚架结构抗火数值模拟研究及结构防火设计提供参考。

Full scale test on anti-collapse performance of asingle-story steel portal frame in real fire

This paper examined a full scale steel portal frame structure subjected to real fires, and the temperature and displacement were measured at various locations of the structural members. The structural response and the deviation of the ISO standard fire curve from the real fire curves were discussed. The results show that the temperature rise in the fire compartment demonstrates big difference from the standard fire curve, and the temperatures in the upper structural components in the fire room are found higher than the values in the lower components. Structural components without protection collapse rather quickly after fire, and demonstrate large displacements before the peak temperatures are reached in the fire compartment and structural components. It is also found that the steel column directly subjected to fire demonstrates a three-stage behavior, i.e. elongation due to thermal expansion, axial compression, and axial bowing. Deformation at the top of these columns are greater than that at lower locations due to the accumulation of hot smoke at the top of the ceiling. The results from this paper can also be used as important validation references for the numerical modeling and fire protection design of portal frame structures.