Avaliacão de óleo de girassol como aditivo de MAM visando a incorporação de elevadas quantidades de material fresado.

Abstract

The environment is increasingly eroded by human activities in all sectors, being no different in the paving sector, which not only removes materials from the production environment for mixtures, but also produces gases harmful to human health with the high machining and compaction temperatures. In this perspective, it is observed that the civil construction industry, more specifically in the paving sector, has been seeking ways to minimize waste and damage to nature, producing asphalt mixtures that become more sustainable and less aggressive, reusing debris from old coatings and less harmful mixtures, such as MAMs (Warm Asphaltic Mixtures), objects of study in this work. Thus, the objective is to reduce the removal of virgin material from nature, and the intention of this research is to use recycled material from old pavements, called RAP, as a fraction of the composition of the new mixture, in order to change rheological properties, and, consequently, decrease the mixing temperature and compaction of the asphalt coating. the emission of greenhouse gases, maintaining as rheological properties and necessary for the upper layer of the pavement. Seeking to improve the workability of the asphalt binder, CAP 50/70, a viscosity reducing additive that modifies the mixture without altering mechanical characteristics was added to the mixture. For this purpose, we opted for sunflower oil, which comes from an oilseed that is widely produced and marketed not only in the national territory, but throughout the world. This was added to the asphalt binder at a content of 2%, according to preliminary studies. At first, penetration, rotational viscosity and softening point tests were performed, before and after the RTFO (Rolling Thin-Film Oven) procedure to characterize the asphalt binder with and without additive. The SUPERPAVE (Super Performing Asphalt Pavements) methodology was adopted, in which the mechanical tests used were Tensile Strength, Resilience Module and Modified Lottman. Therefore, satisfactory results were obtained from the use of sunflower oil as a viscosity modifier, with a reduction in temperature, which results in an increase in the lubricity of the material, which improves the workability of the mixture, however, the value obtained does not constitute a MAM. Within the scope of the incorporation of recycled material, promising results were obtained in terms of tensile strength and resilience modulus, in which the tested mixtures present greater resistance to traction and permanent deformation demands, due to the greater rigidity caused by the aged material of RAP, while in the analysis of damage caused by induced moisture, the presence of 50% and 70% RAP contents hindered the agglutination of the mixture, not reaching the value ruled by the norm, but the incorporation of lower values reached the expected value.