Estudo da aderência e da absorção de água em argamassas de revestimento com agregados reciclados de PET em substratos de blocos cerâmicos

Abstract

The present work was divided in two main stages, the first one correlated to the study of the mortars with partial replacement of natural small aggregate by recycled aggregate of PET in the percentages of 5%, 15% and 30% in volume; and the second step related to the study of adhesion of these mortars when applied to substrates of ceramic blocks. During the first stage, the capillary absorption, tensile strength and axial compression strength tests were performed. The absorption by capillarity in the mortars showed a considerable decrease as the increase of recycled PET aggregate in the mortar matrix. On the other hand, the analysis of tensile strength in flexion, as well as the axial compression strength, showed an improvement in the tensile strength, that is, as the increase of PET in the mixture occurred, the increase in strength of the material occurred. For the second stage of the study, the different traits studied were applied on a substrate of ceramic blocks, with the presence of the layer of chapisco. After the curing age of the coating, 28 days, the tensile strength test of the coating was carried out, which allowed, through the average results obtained in the pull-out tests, to verify that both mortars met the normative criteria of NBR 13 749 (ABNT, 2013), showing an increase of resistance in traces of 15% and 30% of PET in relation to the others. Thus, it was possible to prove the efficiency of the use of recycled aggregates of PET in partial substitution to the natural aggregate on the matrices of the different mortars evaluated, since the use of the different contents of recycled PET aggregate showed satisfactory gains in the properties of the mortars compared to the reference.