Influence of amorphous silica in perlite on compressive strength and pozzolanic reaction of blended cement paste

Abstract

This research was to determine the amorphous silica in perlitethat affected compressive strength and degree ofpozzolanicreaction by using X-ray diffraction method. In this study, perlite was burnt at different temperaturesof600 oC, 700 oC and 800 oC and different timeof 4, 6 and 8 hr. Perlite and sand were ground to approximately thesame finenessascement. Portland cement type1 was replaced by perlite or ground sand at 20% by weight ofcementitiousmaterial. A water to binder ratio(w/c) of 0.40 was used. The result of X-ray diffraction showedthat theperlite burnedat 600 oC for 4 hr. contained the largestamorphousesilica.From the compressive strength test andthe pozzolanic activity testit was shownthat the amorphouse silica contents affected on compressive strengthand degree of pozzolanic reaction.

Keywords : Perlite X-ray, Diffraction, Analysis, Pozzolanic, Amorphous