Abstract Aluminum alloy shells are increasingly used in public buildings as a supporting structure for roofing enclosure construction in large spaces. In performance-based fire protection design, an empirical design criterion of 150 oC and relevant empirical formulas are used; however, the safety margin and prediction effect are not verified through full-scale experiments, and therefore, the effect of the roof system on the near-roof temperature field in practical engineering is yet to be investigated. In this study, a simulated fire experiment was conducted using a cylindrical aluminum alloy reticulated roof system model. The heat release rate of this restricted fuel fire source during the stable burning stage reached 8.1 MW. Fire Dynamics Simulator (FDS) was used to reproduce experimental results, and the numerical model of the shell member was simplified; further, existing empirical formulas of scholars such as Li were compared. The results indicated that although 150 oC is a large safety margin, it may limit architectural function. The simplified shell model provides an effect-equivalent approach for building thin-walled members in FDS. The shell is the main factor that delays the time required for the near-roof space to reach thermal equilibrium. The existing empirical formulas cannot be used for the studied roof system directly, and they may be improved through coefficient adjustment and other such methods.

中文翻译：

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局部火灾下圆柱形铝合金网状屋面系统的温度场特性

摘要 铝合金外壳作为大空间屋面围护结构的支撑结构，越来越多地应用于公共建筑中。在基于性能的防火设计中，采用150℃的经验设计准则和相关经验公式；然而，安全裕度和预测效果尚未通过全尺寸实验验证，因此，屋顶系统对实际工程中近屋顶温度场的影响还有待研究。在这项研究中，使用圆柱形铝合金网状屋顶系统模型进行了模拟火灾实验。该受限燃料火源在稳定燃烧阶段的热释放率达到8.1 MW。Fire Dynamics Simulator (FDS) 用于重现实验结果，简化了壳构件的数值模型；进一步比较了李等学者已有的经验公式。结果表明，虽然 150 oC 是一个很大的安全裕度，但它可能会限制建筑功能。简化的壳模型为在 FDS 中构建薄壁构件提供了一种等效的方法。外壳是延迟近屋顶空间达到热平衡所需时间的主要因素。现有的经验公式不能直接用于研究的屋面系统，可以通过系数调整等方法加以改进。简化的壳模型为在 FDS 中构建薄壁构件提供了一种等效的方法。外壳是延迟近屋顶空间达到热平衡所需时间的主要因素。现有的经验公式不能直接用于研究的屋面系统，可以通过系数调整等方法加以改进。简化的壳模型为在 FDS 中构建薄壁构件提供了一种等效的方法。外壳是延迟近屋顶空间达到热平衡所需时间的主要因素。现有的经验公式不能直接用于研究的屋面系统，可以通过系数调整等方法加以改进。