Zhang Shaofeng, Liu Ronggui, Lu Chunhua, Hong Junqing, Chen Chunhong, Xu Jiajing
School of Transportation and Civil Engineering, Nantong University, Nantong 226019, China.
Faculty of Civil Engineering and Mechanics, Jiangsu University, Zhenjiang 212013, China.
Materials (Basel). 2023 Sep 20;16(18):6310. doi: 10.3390/ma16186310.
Nano-SiO (NS) is widely used in cement-based materials due to its excellent physical properties. To study the influence of NS content on a cement paste and the interfacial transition zone (ITZ), cement paste samples containing nano content ranging from 0 to 2% (by weight of cement) were prepared, and digital image correlation (DIC) technology was applied to test the mechanical properties. Finally, the optimal NS content was obtained with statistical analysis. The mini-slump cone test showed that, with the help of superplasticizer and ultrasonic treatment, the flowability decreased continuously, as the NS content increased. The DIC experimental results showed that NS could effectively improve the mechanical properties of the cement paste and the ITZ. Specifically, at the content level of 1%, the elastic modulus of cement paste and ITZ was 20.95 GPa and 3.20 GPa, respectively. When compared to that without nanomaterials, the increased amplitude was 73.50% and 90.50%, respectively. However, with the further increase in NS content, the mechanical properties decreased, which was mainly caused by the agglomeration of nanomaterials. Additionally, the NS content did not exhibit a significant effect on the thickness of the ITZ, and its value was maintained at 76.91-91.38 μm. SEM confirmed that NS would enhance the microstructure of both cement paste and ITZ.
纳米二氧化硅（NS）因其优异的物理性能而被广泛应用于水泥基材料中。为了研究NS含量对水泥净浆及界面过渡区（ITZ）的影响，制备了纳米含量范围为0至2%（水泥重量）的水泥净浆样品，并应用数字图像相关（DIC）技术测试其力学性能。最后，通过统计分析得出了最佳NS含量。小型坍落度试验表明，在高效减水剂和超声处理的帮助下，随着NS含量的增加，流动性持续下降。DIC试验结果表明，NS能有效改善水泥净浆和ITZ的力学性能。具体而言，在1%的含量水平下，水泥净浆和ITZ的弹性模量分别为20.95 GPa和3.20 GPa。与不含纳米材料的情况相比，增幅分别为73.50%和90.50%。然而，随着NS含量的进一步增加，力学性能下降，这主要是由纳米材料的团聚引起的。此外，NS含量对ITZ的厚度没有显著影响，其值保持在76.91 - 91.38μm。扫描电子显微镜（SEM）证实，NS会增强水泥净浆和ITZ的微观结构。
