SiO_2溶胶对硅酸盐水泥性能的影响研究

Effect of silica sol on properties of Portland cement

初步研究了2种不同的硅溶胶对硅酸盐水泥浆体流动性、凝结时间、安定性以及对水泥硬化浆体的抗折强度和抗压强度的影响,并利用XRD分析了其对水泥性能的影响机理。结果表明,2种硅溶胶均具有良好的水泥适应性,能明显地改善硅酸盐水泥的力学性能,JN-40硅溶胶和SP-40硅溶胶的最佳掺量分别为1.5%和1.0%,硅溶胶的掺入能有效地减少水泥硬化浆体中氢氧化钙的含量,促进水泥的水化反应。

The effect of two different SiO2 sols （nano-silica） on the fluidity, setting time,and soundness of cement paste and tensile strength and compressive strength of the cement hardened paste were investigated carefully. The influencing mechanism on cement properties was analyzed with XRD. The results show that two SiO2 sols have nice adaptability to cement,and can signifi- cantly increase the mechanical properties of the Portland cement. The optimal amount is 1.5% and 1.0% of the mass of cement for JN-40 SiO2 sol and SP-40 SiO2 sol,respectively. The adding of SiO2 sol can effectively reduce the amount of portlandite in the cement hardened paste,so that the hydration can be accelerated.