Investigation for Reaction Mechanism of Nano-Silica-Modified Cement-Based Composite Materials

Abstract

Analysis is conducted by using XRD and TGA-DTA of the changed properties of cement-based composite materials modified by nano-silica. As show by the analysis, after the modification, Ca(OH)₂ crystallization decreases, with grains finer and of no regular shape. Moreover, there is an increase in hydrates produced and hence increased strength. In addition to micro mechanic tests, SEM tests are done of the micro morphology of the modified cement motar and such findings are obtained as increased rate of hydration, increased production of hydrates, more compacted structure with time and hence increased strength and durability. Furthermore, Nano-silica proves to be effective in modifying basic properties of setting-time of cement motar and the different fluidity of cement paste.

Keywords:

• Nano-silica
• modification
• mechanism analysis
• SEM observation