Aplicação de agregados de resíduos de construção e demolição na produção de concreto

Abstract

Civil construction produces billions of tons of waste every year. Methods of reduction and reuse, management, and their final disposal have been taken into account in the last decade, along with the large emission of carbon dioxide, emitted during the extraction of natural aggregates. Taking into account the global and national situation regarding the generation of construction and demolition waste, the feasibility of using it to replace it as recycled aggregate in fractions of the natural coarse aggregate in the concrete mixture was studied. It was verified the properties of the recycled aggregate, in terms of granulometry, specific mass and water absorption in order to adjust a dosage and characterize the constructive element in the concrete mixture for making paver blocks. The conformity required by the requirements established in ABNT NBR 9781:2013 and ABNT NBR 5739:2018 was verified regarding the compressive strength of the molded specimens and pavers. The results were obtained according to the normative procedures for the four studied concrete mixes, Ref., AR25, AR50 and AR75, where AR 25 showed satisfactory results in terms of compressive strength and AR50 was the aggregate replacement limit to not significantly affecting in the mechanical properties of concrete.