杨   光^{1 ,2} ,  滕梦丹¹  ,  罗   薇^{1 ,2}  ,  井文强^{1 ,2}

( 1 .  西安欧亚学院 人居环境学院 ，陕西 西安 710065 ;

2.  城市智慧建造陕西省高校工程研究中心 ，陕西 西安 710065)

摘   要 ：该研究旨在探究纳米二氧化硅  (NS) 和聚乙烯醇纤维  (PVA)对水泥基三元修补材料流动性及力学性能的影响，并利用计算机断层扫描  (CT) 技术与 DRAGONFLY 图像处理平台对修补材料的孔隙结构进行三维重建和定量表征。研究选用普通硅酸盐水泥  (OPC)、铝酸盐水泥  (CAC)和二水石膏(CS)作为胶凝材料， 通过改变 NS 和 PVA 的掺量，分析其对修补材料性能的影响。结果表明： NS 的最佳掺量为 3% ,  此时修补材料的 28 d 抗压强度较三元体系提高了9. 4% ,  而 PVA 的最佳掺量为 0. 75% ,  能显著提升修补材料的抗折和抗压强度。CT 扫描和三维重建揭示了不同掺量下试件内部孔隙结构的空间分布特征，其中 NS 的加入显著降低了孔隙率，而 PVA 的加入则增加了孔隙率。本研究为水泥基修补材料的优化提供了实验依据，并对理解材料内部结构与宏观性能的关系提供了新视角。

关键词：修补材料 ；纳米二氧化硅 ；聚乙烯醇纤维 ；CT 扫描 ；定量表征

中图分类号：TU528 . 59            

文献标志码：A           

文章编号： 1005- 8249   (2024)  06- 0006- 08

DOI:10. 19860/j.cnki.issn1005 - 8249.2024.06.002

YANG Guang^{1 , 2}  ,  TENG Mengdan¹  ,  LUO Wei ^{1 , 2}  ,  JING Wenqiang^{1 , 2}

( 1 . School of Human Settlements and Civil Engineering ,  Xi ’an Eurasia University ,

Xi ’an 710065 ,  China;  2. Engineering  Research Center of Urban Intelligent

Construction ,  Universities of Shaanxi Province ,  Xi ’an 710065 ,  China)

Abstract: The aim of this study is to investigate the effects of nanosilica (NS) and polyvinyl alcohol fiber (PVA) on the flow and mechanical properties of cementitious ternary repair materials, and to reconstruct the pore structure of the repair materials in three dimensions and quantitatively characterize them using computed tomography (CT) technology and DRAGONFLY image processing platform. Ordinary silicate cement (OPC), cement aluminate (CAC) and gypsum dihydrate (CS) were selected as cementitious materials for the study, and their effects on the properties of the repair materials were analyzed by changing the dosage of NS and PVA. The results showed that the optimal dosage of NS was 3%, at which the 28-day compressive strength of the repair material increased by 9.4% compared with the ternary system, while the optimal dosage of PVA was 0.75%, which could significantly improve the flexural and compressive strength of the repair material.CT scanning and three-dimensional reconstruction revealed the spatial distribution characteristics of the internal pore structure of the specimens under different dosages, in which the addition of NS significantly reduced the porosity, while the addition of PVA increased the porosity. The addition of NS significantly decreased the porosity, while the addition of PVA increased the porosity. This study provides an experimental basis for the optimization of cementitious repair materials and a new perspective for understanding the relationship between the internal structure and macroscopic properties of materials.

Keywords: repair materials; nanosilica; polyvinyl alcohol fibers; CT scan; quantitative characterization

*基金项目：2022 年陕西省大学生创新创业项目  (S202212712001 ) ;  西安欧亚学院技术服务专项项目  (OYGJS- 2021007) ;  西 安欧亚学院科研创新团队  (2021 XJD01 ) ;  西安欧亚学院科研平台  (2022XJPT01 ) 。

作者简介：杨   光 (1981 —) , 男，硕士，副教授，研究方向：水泥基胶凝材料及应用。

收稿日期：2023- 05- 05