超细矿渣粉与硅灰对水泥基注浆材料性能影响机理分析

为提高工业废渣的综合利用率,研制出一种绿色环保高性能的注浆材料。选用超细矿渣粉(UFS)和硅灰(SF)替代一定量的水泥,通过正交试验和极差分析法系统地研究了在不同水灰比下掺入不同含量的超细矿渣粉、硅灰以及聚羧酸减水剂(PCE)对注浆材料性能的影响,并对优化后的浆液和纯水泥浆液进行了性能对比及微观试验。结果表明:当超细矿渣粉质量分数从18%增大到20%时,可以增强浆液流动性能,硅灰可以提高结石体抗压强度并减小浆液泌水率,聚羧酸减水剂对降低浆液黏度具有显著效果;以28 d抗压强度和黏度为主要指标,得到浆液的较优配比为水灰比0.70、超细矿渣粉掺量20%(质量分数)、硅灰掺量12%(质量分数)、聚羧酸减水剂掺量0.16%(质量分数)。优化后的浆液泌水率、抗压强度及抗折强度均优于纯水泥浆液。掺入超细矿渣粉和硅灰后,浆液内部生成了钙矾石(AFt)和水化硅酸钙(C-S-H)等凝胶,填充了颗粒间的孔隙,使优化后的浆液结石体强度增大。

Influence Mechanism Analysis of Ultrafine Ground Granulated Blast Furnace Slag and Silica Fume on Properties of Cement-Based Grouting Material

In order to improve the comprehensive utilization rate of industrial waste residue, a green and high-performance grouting material was developed. Ultrafine ground granulated blast furnace slag (UFS) and silica fume (SF) were used instead of a certain amount of cement, and the influences of different content of UFS, SF and polycarboxylate superplasticizer (PCE) on properties of grouting materials were systematically studied by orthogonal test and range analysis method under different water-cement ratios. The properties of the optimized slurry and pure cement slurry were compared and the microscopic tests were carried out. The results show that the slurry flow performance is enhanced when the mass fraction of UFS increases from 18% to 20%. SF can improve the compressive strength of stone body and reduce the bleeding rate, and PCE has a significant effect on reducing the viscosity of slurry. Taking 28 d compressive strength and viscosity as the main indexes, the optimal ratio of slurry was obtained as water-cement ratio 0.70, UFS content 20% (mass fraction), SF content 12% (mass fraction), and PCE content 0.16% (mass fraction). The optimized slurry has better bleeding rate, compressive strength and flexural strength than the pure cement slurry. After the addition of UFS and SF, ettringite (AFt) and hydrated calcium silicate (C-S-H) gels filled the pores between particles were generated in the slurry, resulting in the increase of the strength of the optimized slurry stone body.