PRODUCTS OF ALKALI-ACTIVATED CALCAREOUS FLY ASH AND GLASS CULLET

I. Papayianni, S. Konopisi, K. Datsiou, F. Kesikidou

Abstract: Geopolymerisation comprises a promising field of research, which deals with the rich in aluminosilicates solid wastes and byproducts (such as fly ash, recycled glass cullet), which are converted into useful products via alkaline activation process and heat curing. The fly ash used in this study is a calcareous one, which is the only type produced in Greece from the combustion of lignite. In this paper, mixtures of fly ash with glass cullet, deriving from windshields, are investigated and in particular, the mechanical characteristics and physical properties of colored mixtures that may be used for the manufacture of precast products Four trial mixes were studied experimentally, by forming prismatic (40x40x160 mm) specimens and small slabs (200x200x25mm). The tests of the prismatic specimens include the determination of the compressive and flexural strength, the elastic properties and the porosity at 7-d, 28-d and 90-d age. Volume deformation measurements were also carried out at 28-d age. The mechanism of strength development was monitored by using SEM microscopy, X-ray diffractometer and FTIR spectroscopy. The small slabs were tested in relation to their resistance to abrasion, impact strength, flexural strength and physico-chemical properties

Keywords: Calcareous fly ash, glass cullet, alkali-activation, mechanical strength, physic-chemical properties

DOI: https://doi.org/10.15623/ijret.2014.0325008