在耐火自愈混凝土中验证了细菌生存的热模型
Ajitanshu Vedrtnam1,2, Kishor Kalauni3,4, M T Palou3
1Institute of Construction and Architecture, Slovak Academy of Science, Bratislava, 84503, Slovakia. ajitanshu.m@invertis.org.
Scientific reports
|August 1, 2025
概括
这项研究模拟了火灾期间在自我愈合的混凝土中的细菌存活率. 碳纤维-水泥糊封装保护细菌数小时,不像凝,强调保护层厚度对基础设施弹性的重要性.
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.
- 生物技术是生物技术.
背景情况:
- 基于细菌的自我愈合混凝土通过微生物碳酸沉提供可持续的基础设施维修.
- 火灾期间的高温威胁到细菌的生存能力,并损害了自我愈合的能力.
研究的目的:
- 开发和验证一种传热模型,预测火灾条件下混凝土中封装细菌的存活率 (ISO 834).
- 为了评估不同的封装材料和厚度在保护细菌免受极端热量的有效性.
主要方法:
- 采用了一种经过验证的传热模型,包括辐射热扩散,多层封装的热性能和细菌失活值.
- 该模型使用实验数据验证了在200°C至800°C的温度下对细菌活性的实验数据.
- 模拟评估了碳纤维水泥糊和凝封装的生存时间,并对封装厚度进行了灵敏度分析.
主要成果:
- 碳纤维-水泥糊封装显著延长了细菌的生存时间,在200°C下提供近20小时,在800°C下提供4小时.
- 基于凝的封装提供了最小的保护,不能超过200°C.
- 封装厚度至关重要,层≥1.75毫米提供了更长的细菌保护.
结论:
- 经过验证的传热模型提供了一个预测工具,用于评估火灾暴露下的自我愈合混凝土中的微生物存活率.
- 优化多层封装策略,特别是厚度,对于保持细菌功能和在混凝土结构中实现火灾后自我愈合至关重要.
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