Rubberized mortar: The influence of aggregate granulometry in mechanical resistances and acoustic behavior

Abstract The incorporation of rubber waste from tires into cementitious elements has become an increasingly recurrent practice, since this activity fosters the idea of sustainable construction. The use of rubber as an aggregate in the mortar promotes the correct destination of this residue, becoming inert, promoting the hygiene of the environment. Many researchers have studied the physical and mechanical behavior of rubberized mortar. However, particle geometry analyzes are scarce. This research aims to study the incorporation of rubber tire residues in mortars in two grades of granulometry, i.e., spheroids (S) and fibers (F), replacing the conventional aggregate in 7.5%, 15% and 30%. Density, compressive strength, flexural strength, microstructure and sound attenuation tests were performed. Rubber mortars showed a reduction in density of up to 34.6% compared to conventional mortar, consequently resulting in a reduction of approximately 4 times in compressive strength. However, there is a better acoustic behavior, especially when the rubber is used in fiber format, which presents 29.70% and 42.54% of attenuation enhancement for 15% of fiber waste tire rubber, considering P- and S-waves, respectively.