Correlação entre variáveis de densificação do compactador giratório e resistência à deformação permanente de misturas asfálticas convencionais e com resíduos

Abstract

When comparing the Superpave and the Marshall asphalt mixture design methodologies, an important advantage of the Su-perpave methodology is the compaction curve. It has been established for dense mixes, such as Hot Mixture Asphalt (HMA), that cer-tain areas in this graph can differentiate mixtures in terms of workability and resistance to permanent deformation. In the present study, the Compaction Densification Index (CDI) and the Traffic Densification Index (TDI) were obtained and correlated to the mixture resis-tance to permanent deformation. Three mixtures were analyzed: (i) one with 100% of granitic aggregates, (ii) one with 50% of granitic aggregates and 50% of steel slag, and (iii) one with 50% of granitic aggregates and 50% of Construction Solid Waste (CSW). Digital Image Processing (DIP) was used to determine the angularity and roundness of the aggregates. Those properties affect the resistance to permanent deformation. Results from dynamic creep (samples compacted with two different air voids contents) and traffic simulation tests were correlated to CDI and TDI values. The results indicated that these variables can be used to predict permanent deformation, even when wastes are used as aggregates in HMA’s. The characterization with DIP techniques showed that the granite aggregate has a less spherical shape in comparison to the byproducts. The mixture with granite aggregate has a more rigid structure, because there is a greater interlock and internal friction between the aggregates, leading to better performance with respect to permanent deformation.