Misturas asfálticas recicladas a quente com incorporação de elevado percentual de fresado como alternativa para camada de módulo elevado

Abstract

The high modulus asphalt mixtures (EME) are constituted by an asphalt binder of low penetration and aggregates that have a dense grading curve providing high resistance to permanent deformation and shear stresses. The recycled hot mixtures asphalt (RHMA) with the incorporation of high percentage of reclaimed asphalt pavement (RAP) have potential for the use as an alternative material for the mentioned technique (EME). Its viability is given by the fact that the RAP oxidized binder has higher stiffness (low penetration), and also by the economy that can be achieve with the use of raw material from recycling with potential lower cost. This paper presents a study of the potential use of different RHMA with high percentages of RAP as a base and intermediate course of pavements, such as: (i) Mixture I, composed exclusively by RAP as aggregate; (ii) Mixture II, composed by 75% of RAP and 25% of natural aggregates; (iii) Mixture III, composed by 75% of RAP and 25% of asphalt plant refuse aggregates. Thus, besides the characterization of these materials in the laboratory, computational analyzes were performed based on the Finite Element Method (FEM). The values of displacements, deformations and stresses obtained for the different asphalt pavement structures composed by these mixtures were evaluated and, from that, the traffic that they were able to withstand was calculated. The results showed that the high RAP RHMA could compose structures that can be used on medium and high volume traffic roads.