TONG Yu,YAN Haimin,WANG Zhaoning,DING Xiangqun,WAN Ye

(School of Materials Science and Engineering，Shenyang Jianzhu University，Shenyang 110168,China)

Abstract:Nano-silica particles in different size were used to partially replace silica fume in the optimized mixing ratio of impermeable concrete.Detailed investigations were carried out to reveal the contribution of the particle size and content of nano-silica on the compressive strength and chloride ion penetration resistance of the as-prepared cement mortar.The results show that the naphthalene-based water reducing agent has better compatibility with nano-silica to realize the uniform dispersion of nano-silica in water-based suspension systems.As the particle size of nano-silica decreases or the amount increases,the compressive strength of cement mortar at each age shows a trend of first increasing and then decreasing,while the 6 h electric flux obtained from the anti-chloride ion penetration measurement first decreases and then increase.Nano-silica can improve the internal structure of cement mortar and increase the compactness of the structure.However,if the particle size is too small or the content is too high,the performance of cement mortar decrease apparently due to the poor dispersion of silica nanoparticles.

Keywords:nano-silica；cement mortar；compressive strength；compactness

中图分类号： TU375                            文献标志码：A

文章编号：1008-5548(2022)05-0011-06

DOI:10.13732/j.issn.1008-5548.2022.05.002

收稿日期： 2022-02-09， 修回日期：2022-04-20，在线出版时间：2022-07-09 20:47。

基金项目：辽宁省“兴辽英才计划”项目，编号：XLYC2002005。

第一作者简介：佟钰(1972—)，男，副教授，博士，研究方向为新型建筑材料的制备与应用。E-mail:tong_yu123@hotmail.com。