Effect of various NaOH molarities and various filling materials on the behavior of fly ash based geopolymer composites

Among the recent research interests in the construction section, Geopolymers, represent a rising trend due to their significant performance in terms of strength and long term properties. In this research, an attempt was conducted to examine the effect of using different filling materials and the effect of different NaOH concentrations on the properties of the resulted composites. Strength properties, physical properties, abrasion resistance, and freezing-thawing behavior were tested along with a microstructural characterization that included scanning electron microscopy (SEM) and X-ray diffraction (XRD). In general, the effect of including crushed limestone and waste foundry sand was beneficial in terms of the general properties of the fabricated specimens. Also, the microstructural analyses showed a compact matrix that could be considered in line with the obtained results from the other tests.