Avaliação do potencial de resíduos de porcelanato como substitutos do agregado graúdo em concretos convencionais

Abstract

The construction industry plays a key role in economic and social development, but it is associated with high consumption of natural resources and the generation of waste. Among these materials, porcelain tile scraps and offcuts resulting from the handling, transportation, and installation of these floor and wall tiles are particularly noteworthy. The objective of this study was to evaluate concrete produced with porcelain tile waste as a substitute for natural coarse aggregate. The methodology consisted of producing experimental concrete mixtures based on the IPT/EPUSP method. First, all aggregates and their respective compositions were characterized, followed by the production of concrete in which the natural coarse aggregate was replaced with recycled porcelain tile aggregate at replacement rates of 25%, 50%, and 75% by volume (ARP 25, ARP 50, and ARP 75), in addition to the reference mix (REF) with 0% replacement of natural coarse aggregate. Tests were conducted for axial compressive strength, tensile strength under diametral compression, capillary water absorption, and digital image analysis of test specimen cross-sections, using the software ImageJ and Ilastik. The results showed that the mixtures exhibited adequate consistency in the fresh state, with slump values maintained within the range established for Class S160. In the hardened state, the concrete with 50% replacement exhibited an average compressive strength of 17.78 MPa at 28 days, a value close to that of the reference concrete (17.38 MPa), associated with the lowest coefficient of variation (3.7%). In diametral compression-tension tests, the ARP 75 concrete achieved an average strength of 2.7 MPa at 28 days, approximately 19.7% higher than the reference (REF). Capillary water absorption increased gradually as the replacement content increased, without compromising the overall performance of the mixtures. Digital image analysis revealed a homogeneous distribution of the recycled aggregate, proving to be a complementary tool for interpreting the influence of porcelain tile waste on the physical and mechanical performance of the concretes. It can be concluded that porcelain tile waste has the potential to be used as a recycled coarse aggregate in concrete production, thereby reducing the consumption of natural aggregates. These results underscore the research's contribution to the development of more sustainable solutions in the construction industry, in line with the Sustainable Development Goals (SDGs) of the 2030 Agenda, particularly those related to innovation and responsible consumption and production. [resumo fornecido pelo autor]