对选择的标准双钢和精双钢不钢等级的火灾后强度保留因素的量化
Mariusz Maslak1, Krzysztof Pancikiewicz2, Michal Pazdanowski1
1Faculty of Civil Engineering, Cracow University of Technology, Warszawska 24, 31-155 Cracow, Poland.
Materials (Basel, Switzerland)
|January 23, 2024
概括
这项研究量化了双重不钢的火灾后机械性能. 结果证实了一些保留因子估计,但挑战了在暴露于火灾后在瘦双层档次中加强的说法.
科学领域:
- 材料科学 材料科学 材料科学
- 结构工程 结构工程
- 金工业是金工业的一个方面.
背景情况:
- 双重不钢 (DSS) 越来越多地用于建筑.
- 了解它们在暴露于火灾后的性能对于结构安全至关重要.
- 关于DSS火灾后性能的现有研究,特别是精益双层等级,显示了一些不一致性.
研究的目的:
- 实验量化特定双重不钢等级的火后强度和可塑性的保留因子.
- 为了比较模拟火灾暴露后标准双 (DSS 22% Cr) 和精双不钢 (LDSS) 的行为.
- 验证或完善现有的模型,以预测双重不钢的火灾后机械性能.
主要方法:
- 对两种双重不钢等级进行实验测试:X2CrNiMoN22-5-3 (DSS) 和X2CrMnNiN21-5-1 (LDSS).
- 在各种场景下模拟火灾暴露,然后进行受控冷却.
- 在热处理后评估机械性能,包括强度和柔性.
- 分析微观结构变化及其与机械性能的相关性.
主要成果:
- 实验结果通常与双重不钢的火灾后保留因子的一些定量估计一致.
- 在加热过程中对永久性结构变化的抵抗被确定为影响火灾后性能的关键因素.
- 一个值得注意的发现是,与之前的一些报告相反,在高温加热后的LDSS等级中没有证实火灾后的显著强化.
- 在某些情况下,由于火灾引起的结构变化,观察到易受脆性骨折的增加.
结论:
- 该研究提供了关于特定双重不钢的火灾后性能的关键实验数据.
- 虽然一些现有的预测模型得到了支持,但另一些需要根据这些发现进行修订.
- 在火灾条件下微观结构稳定的关键作用是突出在结构应用中双重不钢.
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