对受局部火灾影响的结构钢梁进行实验研究
Selvarajah Ramesh1, Lisa Choe1, Chao Zhang1
1National Institute of Standards and Technology, 100 Bureau Drive, Gaithersburg, MD 20899-1070, USA.
概括
不受保护的钢梁受到局部火灾的影响,由于侧向扭曲曲而失败. 取暖条件和端束显著影响火灾下的光束行为,告知预测模型验证.
科学领域:
- 结构工程 结构工程
- 消防安全工程 消防安全工程
- 材料科学 材料科学 材料科学
背景情况:
- 局部火灾对钢结构构成独特的风险.
- 了解未受保护的钢梁在火灾下的行为对于结构安全至关重要.
- 现有的设计方法可能无法完全捕捉复杂的火灾场景.
研究的目的:
- 在局部火灾条件下实验研究未受保护的W16 × 26钢梁在局部火灾条件下的行为.
- 评估不同加热场景 (稳定或短暂) 和终端支条件对光束性能的影响.
- 为火灾暴露的钢结构提供用于验证预测模型的数据.
主要方法:
- 测试简单支和连接到柱子的钢梁标本.
- 使用天然气燃烧器应用稳定或短暂的火力负载.
- 测量热反应,结构屈曲,热释放率和施加力的测量.
主要成果:
- 所有测试的钢梁样本都由于侧向扭曲曲而失败.
- 取暖条件 (稳定/暂时) 和末端限制明显影响了光束的行为.
- 实验数据捕获了局部火灾下的热和结构反应.
结论:
- 侧向扭曲曲是局部火灾中未受保护的钢梁的关键故障模式.
- 火热动态和结构边界条件是影响钢梁火性能的关键因素.
- 实验结果对于完善结构设计方法和消防安全工程的预测模型有价值.
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