Estudo de resíduo da lapidação de vidro para incorporação em argamassas de cimento Portland

Abstract

The building industry is a great consumer of natural resources, and it is currently being investigated ways to reduce or rationalize the consumption of natural products for the production of materials and building components. The incorporation of some solid industrial residues has been shown as an interesting alternative to produce concretes, mortars e concrete blocks, among other applicability of the Portland cement. This study aimed was to analyze the effect of incorporation of the polishing float glass (PFG) in mortars of Portland cement and natural sand. The PGF was used as supplementary material to the cement, replacing the cement mass in the percentages of 5%, 10%, 15%, 20% and 25%. Two series of mortars were produced, the first with water-binder ratio constant and another with constant water-cement ratio. In the development of the research comparisons were made between the characteristics of a reference mortar without addition of the PGF, and properties of mortars produced with different percentages of PGF. The mortars were studied in fresh and hardened state, with analysis of the following characteristics: density in the fresh state; consistency index; water retention; incorporated air content; compressive strength; tensile strength in bending; void ratio; dynamic modulus of elasticity; density in the hardened state and alkali-silica reactivity. In mortars with constant relation water-cement, the use of PFG caused a significant decrease in the consistency index, variation inversely proportional to the percentage of PFG in the mixture. Other properties in the fresh state showed small variations for the two mortars series. In the hardened mortar cement replacement by PGF produced decrease in compressive strength at ages of 7 and 14 days. However, even with reduced consumption of cement, mortar with a higher residue percentage showed a significant increase in their resistance for ages 28, 63 and 91 days of curing. The expansion test as a result of alkali-silica reaction, showed that the incorporation of PFG produces no deleterious effects due to the expansions in the composites studied and, in some cases, even promotes reduction of these expansions. The use of the residue of polishing glass as a partial cement replacement proved feasible to maintain, or even by improving some properties of mortars with PGF.