考虑不同场景的砖木结构古建筑火灾特征研究

Study on fire characteristics of ancient buildings with brick-wood structure under different fire scenes

为探明砖木结构古建筑火场下的特征,定量分析不同火灾场景下,建筑内部温度、烟气浓度等参数的变化。选取中国北方典型的砖木结构体系的四合院韩城党家村贾祖祠为研究对象,采用PyroSim建模分析,研究不同火灾场景下不同时间点的温度、CO浓度、能见度等变化。研究结果表明:贾祖祠主厢房较封闭,火灾中火源周围温度峰值可达750℃,CO质量浓度达到0.003kg/m^3,能见度几乎为0m,风速最高为10m/s且极不稳定;四合院中主厢房空间布局高,火灾中这些参数的影响会导致严重的轰燃现象发生,故此处发生火灾更易产生严重危害。对不同场景的砖木结构古建筑重要火灾因素发展规律的研究,能为古建筑的性能化防火提供科学参考依据。

In order to study the characteristics of ancient buildings with brick-wood structure in the fire scene,the change of internal temperature,smoke concentration and other parameters in the building under different fire scenes was analyzed quantitatively.Taking the actual situation of Jia-ancestral shrine in Dangjia Village of Hancheng City as the research object,which was the typical courtyard house with the brick-wood structure system in north China,the change of temperature,CO concentration and visibility at different time points under different fire scenes was studied by using the PyroSim modeling and analysis.The results showed that the main wing room of Jia-ancestral shrine was relatively closed,and in the fire,the peak temperature around the fire source could reach 750℃,the maximum molar concentration of CO was 0.005 mol/mol,the mass concentration was 0.003 kg/m^3,the visibility was almost 0 m,the maximum wind speed was 10 m/s and extremely unstable.The space layout of the main wing room in the courtyard house was high,and the influence of these parameters in the fire would lead to the occurrence of serious flashover phenomenon,so the fire in this place was more likely to cause serious damage.The research on the development laws of important fire factors for the ancient buildings with brick-wood structure under different fire scenes could provide scientific reference and basis for the performance-based fire protection of ancient buildings.