Análise da absorção de água em argamassas contendo areia de cinza do bagaço da cana-de-açúcar

Abstract

In light of the inadequate disposal of agro-industrial waste in the sugarcane industry, this study aimed to analyze the performance of mortars containing 30% sugarcane bagasse ash (SBAS) as a partial replacement for natural sand, the study proposes its use as a sustainable alternative for the construction sector. Thus, reference and SBAScontaining mortar specimens were cast to evaluate water absorption by immersion and capillarity, as well as the mechanical properties of flexural and compressive strengths. The results showed that the partial replacement with SBAS did not compromise the mortar’s permeability, as the water absorption values, both by immersion and by capillarity, remained similar to those of the reference sample. In the mechanical tests, the results from the flexural tensile strength test did not differ statistically from each other, however, there was a slight increase in the strength value for the sample containing SBAS, evidencing improved compaction of the cementitious composite. Conversely, the compressive strength test results showed an increase of approximately 14.4% with the 30% replacement of natural sand by SBAS, which is attributed to the enhanced granular distribution of the mixture. Microscopic analyses corroborated the obtained results, revealing a more compact microstructure in the mortar containing SBAS compared to the reference. Although both exhibited similar void indices, the images unveiled a denser and more homogeneous cementitious matrix in the SBAS sample due to its finer particle size, which favors better particle packing. Thus, it is concluded that the utilization of SBAS as a partial sand replacement is technically feasible and environmentally advantageous, establishing itself as a sustainable option capable of reducing the consumption of natural resources and the environmental impacts associated with the disposal of agro-industrial waste, without detriment to the material's physical and mechanical properties.