在暴露于高温后,非化Hwangto混凝土的剩余机械和结构性质
Taehyung Kim1, Wonchang Kim1, Hajun Im1
1Department of Fire and Disaster Prevention, Semyung University, Jecheon 27136, Republic of Korea.
Materials (Basel, Switzerland)
|February 27, 2026
概括
将非化Hwangto (NHT) 添加到普通波特兰水泥 (OPC) 混凝土中,可以提高高温机械性能和耐火性. 这种增强与微观结构完整性的保护有关,即使初始强度降低.
科学领域:
- 材料科学 材料科学 材料科学
- 土木工程 土木工程是指土木工程.
- 地质化学 地质化学
背景情况:
- 普通波特兰水泥 (OPC) 的混凝土性能在高温下显著降解,在火灾场景中构成风险.
- 用补充的水泥材料部分替换OPC是一种提高混凝土性能的常见策略.
- 非化Hwangto (NHT),一种韩国粘土,具有作为可持续混凝土添加剂的潜力.
研究的目的:
- 为了评估混凝土的残余机械性能,在暴露于高温后,采用非化Hwangto (NHT).
- 调查NHT替换水平和水与粘合物 (W/B) 比率对热稳定性和能量吸收的影响.
- 了解NHT混凝土增强高温性能背后的微结构机制.
主要方法:
- 用不同的NHT替代水平 (0%,15%,30%) 和W/B比率 (0.41,0.33) 准备了混凝土样本.
- 标本以1°C/分钟的速度被控制加热至700°C.
- 在不同的温度下测量了残余压力强度和能量吸收能力.
主要成果:
- 最初的压力强度随着NHT含量增加而下降,但在高温下残留强度显著提高.
- 使用30%NHT (NHTC-30) 的混凝土在700°C时表现出最高的热稳定性,保持其初始强度的28.2%.
- 在700°C时,NHTC-30表现出优越的柔性和能量消散能力,这归因于金属的形成和保存的微观结构完整性.
结论:
- 将OPC部分替换为NHT有效地提高了混凝土的耐火性和残留结构完整性.
- 在NHT中考利尼特的热激活到甲考林在缓解高温降解方面发挥着至关重要的作用.
- 对于需要在火灾条件下提高性能的应用,NHT混凝土具有潜力,特别是在正常强度的混凝土矩阵中.
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