Reaproveitamento de resíduos plásticos de cabos elétricos em aplicações geotécnicas

Abstract

The rapid growth in the consumption of electrical and electronic equipment has driven the generation of this type of waste on a global scale, imposing increasing challenges to the proper disposal of the polymeric fraction derived from electrical cables, a material of low economic value and difficult to reuse. In Brazil, this scenario is aggravated by structural limitations of the waste management system, even though the National Solid Waste Policy and Decree No. 10,240/2020 establish guidelines for the reverse logistics of electronic products. Motivated by a real demand identified by the company E-Ambiental, from Juiz de Fora, which accumulates the shredded plastic fraction resulting from the separation of electrical cables, this study aimed to investigate the geotechnical reuse potential of this waste through a literature review and an exploratory experimental study. The literature review showed that the reuse of plastic waste in civil engineering is a topic of worldwide interest, with studies from different countries addressing applications such as soil reinforcement and stabilization and the production of sustainable concrete and mortar. In general, the studies indicated that the behavior of the mixtures is strongly influenced by the type, shape, and content of the incorporated waste. For the preliminary experimental study, a residual soil collected on the UFJF campus was used, into which 1% of shredded plastic waste was incorporated. Particle size distribution tests were performed on the waste, along with Proctor compaction and unconfined compressive strength tests on the mixture. The particle size characterization revealed a predominance of particles in the medium to coarse sand range, and the compaction tests indicated slight changes relative to the pure soil, with an increase in maximum dry density from 1.515 g/cm³ to 1.53 g/cm³, and a decrease in optimum moisture content from 27.0% to 25%, behavior consistent with trends found in the literature. On the other hand, the unconfined compressive strength tests showed a moderate reduction, from 0.152 MPa to 0.111 MPa, corresponding to a 27% decrease, which is also consistent with many authors in the literature. The results obtained indicate that, at the content and shape studied, the incorporation of the waste contributed to a moderate decrease in the soil's mechanical strength, highlighting the need for further investigations to evaluate other contents, as well as their combination with stabilizing agents, in order to identify technically more favorable configurations.