纳米对基于水泥的超高性能系统的贡献
Eirini-Chrysanthi Tsardaka1, Evangelia Tsampali1, Maria Stefanidou1
1Laboratory of Building Materials, School of Civil Engineering, Aristotle University of Thessaloniki, 54006 Thessaloniki, Greece.
Materials (Basel, Switzerland)
|August 29, 2024
概括
纳米 (NA) 增强水泥糊的水分和显著提高压力强度随着时间的推移. 这使得NA成为超高性能水泥 (UHPC) 的理想选择,改善机械性能和耐用性.
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.
- 纳米技术 纳米技术
背景情况:
- 纳米材料如纳米 (NS),纳米 (NA) 和纳米氧化物 (NC) 被纳入水泥材料中.
- 每种纳米材料都独特地影响了基于水泥的系统的特性.
- 了解这些影响对于优化材料性能至关重要.
研究的目的:
- 研究NS,NA和NC对水泥糊的新鲜性质和长期压力强度的影响.
- 分析早期的水化行为和微观结构的发展.
- 确定用于增强超高性能水泥 (UHPC) 最有效的纳米材料.
主要方法:
- 在水泥糊中添加1.5%的NS,NA和NC.
- 分析新鲜性质,包括清晨的加水热和X射线衍射 (XRD).
- 长期测量压力强度和开放孔隙度,长达一年.
主要成果:
- 纳米 (NA) 加快了水化热,与增加的水化产品有关.
- 在较晚的年龄段,添加NA导致压力强度增加10%.
- 在28天内,纳米氧化 (NC) 减少了54%的开放孔隙,新鲜性质不受影响.
- 纳米二氧化 (NS) 增加了水化热,但没有显著提高强度.
- 在二氧化碳大气中,NA的结合保留了UHPC的特性,并增强了强度.
结论:
- 纳米 (NA) 优化了基于水泥的系统中的微结构发展和压力强度.
- 在超高性能水泥 (UHPC) 应用中,NA是一种有前途的添加剂.
- 这项研究为提高UHPC在各种条件下的机械性能和耐用性提供了进展.
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