Incorporação de placa de circuito impresso como agregado miúdo na fabricação do concreto para a construção civil

Abstract

In civil construction, substitution of aggregates in concrete manufacturing is a way of reusing materials, reducing accumulation and final disposal of waste. The contemporary technological revolution, which produces and consumes equipment in large scale, is responsible for the growing increase in the generation of electronic waste. There is a latent need to suggest new strategies for the collection, handling, disposal and remediation of electronic waste, which already represents more than 5% of urban waste. The present work aims to evaluate the possibility of replacing the fine aggregate (sand) with the electro-electronic waste, specifically the printed circuit board, in concrete, for use in civil construction. For this purpose, the simple compressive strength and deformation achieved by the simple compression test of the samples were compared without and with 2% and 5% substitution of the electronic residue, as well as Scanning electron microscopy test.For all replacement percentages, the ruptures were columnar. The average values of simple compressive strength and strain obtained in the tests were, respectively: 0% replacement, 10.98 Mpa; 4.40 mm; 2% replacement 12.59, MPa; 2.27 mm; 5% replacement, 10.01 MPa; 2.70 mm. Statistical analysis showed that the substitution of fine aggregate by electro-electronic waste adds resistance to concrete for 2% of substitution, and does not compromise the resistance for substitutions with 5% of residue. Regarding the deformation, the specimens with substitution presented a significant difference for the specimens without substitution. For specimens with 2% replacement the results deformation were slightly lower compared to specimens with 5% replacement.The possibility of releasing heavy metals, components of the printed circuit boards, in the solid concrete structure is considered, which can be verified by scanning electron microscopy.