Influência da adição de fibras de papel Kraft nas propriedades físico-mecânicas de argamassas

Abstract

The disposal of solid waste has become an environmental challenge around the world. The construction industry is among those that generate the most waste and, therefore, had to turn its attention to the development of new ways to recycle or reuse the generated waste. More than 60% of the cement sold in Brazil is made available in bags made of Kraft paper, which, after use, are discarded as construction and demolition waste in sanitary landfills. In order to give a new use to these packages, this study proposed the insertion of Kraft paper fibers from cement packages in controlled additions in mortar mixes, aiming to identify which mix obtained the best results in relation to consistency, density, mechanical resistance to traction and compression, water absorption by capillarity and pullout. For this, the packages were processed with the addition of water to turn into a pulp, which after drying was weighed, humidified and inserted into the mortar traces. The research in question studied three different traits, being 1:2:6, 1:2:7 and 1:2:8 of cement, lime and sand by volume respectively. From there, the mechanical and physical aspects of these traits were evaluated. The collected data were analyzed using linear regression graphs, in order to compare them with the data obtained in the reference traces (without any fiber addition). Mixture 1, with 0.5% fiber addition, obtained an improvement of 33.78% in pullout strength and density in the hardened state 4.9% lower compared to its respective reference mix. Among the traits studied, mix 1 with 0.5% addition was the one that suffered the least loss of mechanical strength in relation to the reference mix.