4 - Use of agro-industrial waste as a filler for structural reinforcement mortars

Abstract

The objective of this work was to study the use of agro-industrial residues in the form of fiber, as filler for structural reinforcement mortars. The fibers used (from pineapple and açaí) were treated by immersion in NaOH solution with a concentration of 0.5%, for a period of 3hours and used in mortars 1:1:6:1.5 by weight (cement:lime:sand:water), in percentages of 0%, 2%, 4%, and 6%. Consistency tests, water retention, incorporated air content, mass density, water absorption by capillarity, and resistance to compression were carried out. The results prove the feasibility of using natural fibers, mainly due to the excellent performance in specific resistance caused by the higher mechanical resistance and lower density obtained by the mortars containing the fibers. This response pattern occurs due to fiber hygroscopy that allows the absorption of cement paste while still fresh. After the material hardens, the absorbed paste forms points of connection and transfer of efforts, due to the formation of ettringite, which leads to the final conclusion that the application of agro-industrial residues in reinforcing mortars is totally beneficial with regard to performance mechanism of the material.