Scanning Electron Microscopy of Metakaolin Based Geopolymer Concrete

Abstract

This work is a Scanning Electron Microscope (SEM) study to investigate the behaviour of Metakaolin based GPC mixes with and without cement and containing recycled concrete aggregate. Three (3) GPC mixes and Normal Concrete mix (NC) designed mingled and tested to achieve the goals of this research. Control specimens were cast from each mix to determine the mechanical properties for each mix. (12) SEM micrographs from carefully selected samples. SEM study confirmed that the presence of recycled concrete aggregate can be a source of generating cracks and fissures. The un-hydrated cement particles in recycled aggregate can contribute to further hydration when contact with water. Also, the metakaolin based GPC matrix with natural aggregate showed enormous with unrealized morphology, which indicates amorphous. Finally, the replacement of 20% of Metakaolin with cement led to enhance mechanical properties.