通过固体碳酸沉提高超高性能混凝土的性能和可持续性
Yi Han1, Runsheng Lin2, Xiao-Yong Wang3,4
1Department of Integrated Energy and Infra System, Kangwon National University, Chuncheon-Si, 24341, South Korea.
概括
这项研究引入了一种新的方法,通过将其转化为固体碳酸,将二氧化碳 (CO2) 纳入超高性能混凝土 (UHPC). 这种间接的二氧化碳增加提高了UHPC的性能和可持续性,减少了每单位强度的二氧化碳排放.
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.
- 环境科学 环境科学
背景情况:
- 超高性能混凝土 (UHPC) 具有卓越的强度和耐久性.
- UHPC的密集微观结构通过碳化固化防止直接的二氧化碳 (CO2) 捕获.
- 开发可持续的建筑材料对于减少环境影响至关重要.
研究的目的:
- 研究间接将捕获的二氧化碳 (CO2) 添加到超高性能混凝土 (UHPC) 的可行性和影响.
- 评估从CO2中获得的固体碳酸 (CaCO3) 的UHPC的性能和可持续性.
- 评估这种方法在混凝土生产中减少二氧化碳排放的潜力.
主要方法:
- 用氧化将气态CO2转化为固体CaCO3.
- 固体CaCO3 (2,4和6重量%) 被添加到HHPC混合物中.
- 进行了宏观测试 (强度,超声速,电阻) 和微观分析 (加水热,TGA).
- 二氧化碳排放量通过压力强度和电阻在28天后得到正常化.
主要成果:
- 间接的二氧化碳添加并没有对UHPC性能产生负面影响.
- 与对照组相比,使用固体CO2的UHPC显示出早期强度,超声速和电阻率的改善.
- 通过添加捕获的二氧化碳,加快了水泥的水化速度.
- 使用二氧化碳的超高压电压表现出较低的每单位压力强度和阻力二氧化碳排放.
结论:
- 通过固体CaCO3间接添加CO2是一种增强UHPC性能的可行方法.
- 这种方法为混凝土中二氧化碳封存提供了一条途径,提高了材料的可持续性.
- 这些发现表明,减少高性能混凝土的环境足迹是一个有希望的战略.
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