The Promotion of Nano-SiO2 on the Compressive Strength of Alkali-Activated Materials

Nanomaterial which has high activity is widely used in the modification of cement-based materials due to its physical filling and chemical bonding. This paper mainly studied the influence of nano-SiO2 on the compressive strength of the alkali-activated materials, using XRD and SEM technology to analyze the mineral composition microstructure of alkali-activated materials, modification effect, etc. The results show that the doping of nano-SiO2 can enhance the compressive strength of alkali-activated materials. Under the condition of fixed water-binder ratio and alkali content, the optimum dosage of nano-SiO2 is 4%. When the content is 4%, the intensity of 28 days is increased by 26.81% compared with the blank sample, and compressive strength of 94.93 MPa is reached. By XRD and SEM, we can find a large number of CSH and a certain amount of CH in the sample. The promotion effect of nano-SiO2 on the alkali-activated materials provides a better support for the application of the alkali-activated materials in reality.