结构耐火设计中室内温度预测模型的对比研究

Comparative study on the prediction model of enclosure temperature in fire resistance design

基于现场实验的实验结果,对比研究了《建筑钢结构防火技术规范》推荐的单区域模型和CFA ST双区域模型两种室内温度预测模型。结果表明,《建筑钢结构防火技术规范》推荐的单区域模型用于结构耐火设计时的温度预测是合适的。当火源功率较小时,CFA ST会过高预测热烟气层的温度值;火源功率较大时,CFA ST与其模型假定不符,难以得出正确的结果。而一般结构耐火设计时的火源功率都较大,因此CFA ST不适用于结构耐火设计时的温度预测。

Based on the result of the spot experiments, the onezone enclosure temperature prediction model recommended by technical code and the two-zone model from CFAST were comparatively studied. The result showed that the one-zone model is appropriate to predict the temperature during the fire resistance design; CFAST will result in a higher prediction of the smoke layer when the fire load density is low, and when the fire load density is high, the model will have a screw loose and can not get the right result. Thereby CFAST model is not suitable for temperature prediction in fire resistance design to buildings, as the fire load density is mostly huge.