红色砂石-石-石膏-水泥复合水泥材料的制备和微力学
Chuiyuan Kong1, Bin Zhou1,2, Rongxin Guo1
1Yunnan Key Laboratory of Disaster Reduction in Civil Engineering, Faculty of Civil Engineering and Mechanics, Kunming University of Science and Technology, Kunming 650500, China.
Materials (Basel, Switzerland)
|July 14, 2023
概括
红色砂岩 (RS) 提高了水泥材料的流动性,但降低了强度. 将石膏 (PG) 添加到RS水泥复合材料中,通过形成石和C-(A) -S-H凝来增强后来的强度,从而激活RS火山灰的特性.
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.
- 地质化学 地质化学
背景情况:
- 红色砂岩 (RS) 是一种潜在的补充性水泥材料.
- 了解其物理和化学特性对于开发复合混凝土材料至关重要.
- 需要对RS的火山灰活动和石 (PG) 对其性能的影响进行研究.
研究的目的:
- 研究红色砂石水泥 (RS-OPC) 和红色砂石-石水泥 (RS-PG-OPC) 复合材料的性能.
- 分析RS含量对流动性,机械强度和微力学的影响.
- 评估使用PG增强RS火山灰活动的可行性.
主要方法:
- 关于RS-OPC和RS-PG-OPC复合材料的特性.
- 使用XRD,FTIR,TG-DTG和SEM分析水化产品和微结构.
- 在不同替换级别下对流动性和机械强度 (压力强度) 的评估.
主要成果:
- 在RS-OPC中,RS增强了流动性,但降低了机械强度,具有显著的强度损失 (>25%的替换).
- 证实了RS的低火山灰活动;它主要起到充填作用.
- 将5%的PG添加到RS-PG-OPC中减缓了最初的水合,但通过形成乙酸盐和C-A) -S-H凝,提高了后来的机械强度和流动性.
结论:
- 合石添加激活了复合水泥材料中的红色砂岩的火山灰潜力.
- RS-PG-OPC为传统的OPC提供了一个可行的替代方案,特别是在废弃RS丰富的地方.
- 这种方法可以减少对采矿OPC原材料的依赖,并有效利用废物资源.
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