NUNES, A. T. R.; NUNES, Aluska Thayuanne Rocha.
Résumé:
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.