The different action mechanisms of silica and alumina nanoparticles in lime-pozzolan pastes

Abstract

The purpose of this study is to compare the mineralogical and the chemical modifications of lime-pozzolan pastes with increasing proportions of nano-silica (NS) and nano-alumina (NA) particles, respectively. The action of the nanoparticles was found different and the results can explain the variation of physical and mechanical properties that were recorded in previous studies. NS action was synergetic to the pozzolanic reaction between the binders, whilst NA action was found competitive to the pozzolanic reaction as it strengthens carbonation. Analysis with XRD and ATR-FTIR advocate this result revealing the reaction mechanisms.

Keywords

• Nano-silica
• Nano-alumina
• Lime-pozzolan
• Reaction mechanism