01592562

Component

This study evaluates the influence of morphological properties of aggregates on the mechanical behavior of asphalt mixtures. For that, two aggregates with different characteristics, i.e., round river gravel and crushed gneiss, are used in the research. Laboratory tests are conducted to characterize morphological properties of the aggregates following traditional methodologies and using a modern image analysis system, AIMS 2. Six asphalt mixtures containing different proportions of gravel and crushed gneiss are designed according to the Superpave methodology and evaluated in mechanical performance tests. The results obtained indicate that the use of aggregates with generally undesired morphological characteristics (e.g., low angularity and roughness), such as the gravel evaluated in this study, may have the potential to be used in the composition of asphalt mixtures resistant to damage, especially if they are crushed and/or combined to more angular aggregates with rougher surface texture. Furthermore, the results also point to the need for the consideration of methodologies to characterize aggregate morphological properties that are more objective, provide more direct measurements, and are more independent of the skills of the technician who performs the tests than currently used procedures, such as those adopted by Superpave. This would lead to the fabrication of more economical, durable, and long lasting mixtures.

This paper was sponsored by TRB committee AFK30 Standing Committee on Characteristics of Nonasphalt Components of Asphalt Paving Mixtures.

01584066

16-5108

English

18p

2016

Transportation Research Board 95th Annual Meeting

Digital/other

Figures; Photos; References; Tables

Aggregates; Asphalt mixtures; Crushed rock; Geomorphology; Gneiss; Gravel; Mechanical properties; Superpave

River gravel

Highways; Materials; Pavements

Transportation Research Board Annual Meeting 2016 Paper #16-5108

TRIS, TRB, ATRI

Jan 12 2016 6:14PM