Análise da viabilidade técnica da utilização do resíduo de polipropileno como agregado miúdo reciclado para produção de pavers

Abstract

With the increase in the quality of life of the population, the demand for consumption of products also increases, and with it, the disposal and the rampant generation of waste that pollute the environment so much. Of these residues, industrial and post-consumer plastics have stood out, in the form of packaging, toys, lids, among others, of which a large part is made of polypropylene (PP), currently the second most commercialized synthetic polymer in the world and the with the greatest market demand in Brazil. Thus, this work sought to analyze the feasibility of using recycled polypropylene waste (RPP) as a partial substitute for the natural fine aggregate for the production of interlocking pavement pieces (pavers) used in civil construction. For this, physical and mechanical properties of the parts were evaluated, such as compressive strength, dimensional evaluation, water absorption, voids index and specific mass. This depends on the execution of four traces, one of which is a reference, dosed only with natural aggregates, and the other three, with substitutions of 3%, 6% and 9%, by mass, of RPP, named, respectively, RPP0, RPP3, RPP6 and RPP9. The results showed that the insertion of RPP in the concrete influenced the compressive strength of the pavers, so that as the substitution content was increased, the strength gains were reduced; none of the lines met the minimum resistance required by NBR 9781 (ABNT, 2013), which recommends a minimum of 35 MPa. Regarding the dimensional evaluation, the greatest variation was in thickness. The absorptions of the pieces of the four traces were within the limit required by the standard, in which the substitution levels influenced non-linearly, as occurred for the voids index. These were between 9.35% (RPP0) and 20.16% (RPP6), being considered adequate values by the literature. In the specific mass test, there was an improvement in this parameter, since the specific mass decreased and, consequently, the parts became lighter. The use of RPP as a partial substitute for the natural fine aggregate for the production of pavers can be considered technically feasible for environments with limited traffic such as public sidewalks, squares, sidewalks and cycle paths, representing an alternative that contributes to sustainability in civil construction.