基石在超高性能混凝土 (UHPC) 矩阵中的应用,以提高强度和减少收缩
Zhijie Liu1,2,3, Xibo Qi1,3, Yuanhang Lv1,3
1Sanya Science and Education Innovation Park, Wuhan University of Technology, Sanya 572004, China.
Materials (Basel, Switzerland)
|March 13, 2025
概括
将石膏 (PG) 纳入超高性能混凝土 (UHPC) 减少了对环境的影响. 适度的PG水平保持机械性能,提高体积稳定性,提供可持续的建筑材料.
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) 提供了卓越的强度和耐久性,但由于高含量,具有显著的环境缺点,导致二氧化碳排放和资源耗尽.
- 化石 (PG) 是酸生产的副产品,是UHPC中部分水泥替代的潜在可持续替代品.
- 使用PG解决了UHPC生产的环境问题和工业废物的处置挑战.
研究的目的:
- 研究合石膏 (0-40%) 对超高性能混凝土 (UHPC) 的水化动力学,机械性能和体积稳定性的影响.
- 评估石作为一种补充性水泥材料 (SCM),以提高UHPC的可持续性.
主要方法:
- 该研究涉及将不同百分比的合石膏 (PG) 纳入UHPC混合物.
- 监测了水化动力学,并使用X射线衍射 (XRD) 和热重力学分析 (TG) 来分析水化产品.
- 机械性能 (强度) 和体积稳定性 (自身收缩) 通过标准化测试进行了评估.
主要成果:
- 增加石含量通常会延迟水合过程,影响诱导期和峰值水合时间.
- XRD和TG分析表明,PG影响了关键水化产品的形成,改变了微观结构的发展.
- 适度的PG替代 (10-20%) 维持或提高了长期的机械性能,而较高的百分比则对强度产生了负面影响.
- 合石膏的合并显著减少了自身缩,从而提高了UHPC的体积稳定性.
结论:
- 石是超高性能混凝土的可行的补充水泥材料.
- 优化的PG整合可以带来更可持续的UHPC,具有可比或改进的机械性能和增强的体积稳定性.
- 这项研究支持在先进的建筑材料中使用像PG这样的工业副产品来减轻对环境的影响.
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