变电站钢构件及组合板的防火性能

Fire behaviour of steel specimens and composite floor of substation buildings

针对现有规范中缺少电力火灾下钢结构的防火设计方法,基于有限元法对变电站工程中的典型钢构件进行抗火性能研究,发现和标准火灾相比,电力火灾作用下钢构件和组合板的温度更高,耐火极限更低;将有限元模型预测耐火极限与规程预测结果进行对比,发现现有规程推荐的预测方法可准确模拟变电站钢构件的耐火极限,但是钢-混凝土组合板耐火极限的预测方法偏于保守。为提高经济性,本文修正了组合板耐火极限的预测方法。

The existing design standard lacks the design method of the fire protection design under the electrical fire.Based on the finite element(FE)method,the fire performance of typical steel components was investigated in a substation engineering in this study.The research result indicated that compared with the ISO 834 standard fire,steel components and steel-concrete composite floor under the electric fire exhibited a higher temperature and a lower fire resistance.The FE fire resistance were compared with the predicted results using the design standard.It can be found that the predicting method in the design standard can be used to well simulate the fire resistance of the steel specimens.However,for the composite floor,the predicting method of the fire resistance of the composite floor was conservative.To improve the economy,the predicting method of the fire resistance of the composite floor was refined in this paper.