摘要
对目前性能化防火设计中常用的4种火灾作用模型进行了分析和总结,并运用这4种模型对钢结构交错桁架在火灾时的热环境进行了模拟,分析不同火灾作用模型下该体系的结构响应,研究不同火灾作用模型对交错桁架结构性能化抗火设计的适用性。研究表明:火源功率、火灾载及火灾持续时间等因素对钢结构交错桁架的抗火分析具有重要影响。国际标准升温曲线和参数化室内升温曲线不考虑火源功率、建筑通风口等因素,缺乏针对性,分析结果偏于保守;区域模型所得温度偏低,不宜用于交错桁架结构的性能化抗火设计;场模型考虑了火源功率及环境温度分布的不均匀性,和实际火灾较接近,计算结果相对较为准确,可用于结构的性能化防火设计。
Four kinds of fire models, which are commonly used in performance-based fire protection design are analyzed and summarized. The fire environment of steel staggered-truss is simulated using these four models. The effect of different fire models on fire-resistance analysis of steel staggered-truss is explored. And the applicability of fire models to the performance-based fire protection design on steel staggered-truss structure is discussed further. The result indicates that the rate of heat release, fire load and fire duration can make great influence on the fire resistance analysis of steel staggered-truss system. ISO834 and parametric equation approach are lack of pertinence. The results may be too conservative. The temperature obtained by zone model is low, so that it is not suitable for the performance-based fire protection design on this structure. Field model considers the heterogeneity of environmental temperature, and its result is close to the real fire, so that it is commended to the performance- based fire protection design on steel staggered-truss structure.
出处
《灾害学》
CSCD
2010年第1期93-97,共5页
Journal of Catastrophology
基金
国家自然科学基金项目(50706059)
关键词
火灾模型
交错桁架
结构抗火
钢结构
fire model
staggered truss
fire resistance of structure
steel structure
