United States Department of Transportation
i
Evaluation of the Effect of Flat and Elongated Particles on the Performance of Hot Mix Asphalt Mixtures
-
2000-05-01
[PDF-477.06 KB]
Details:
-
Creators:
-
Corporate Creators:
-
Subject/TRT Terms:
-
Publication/ Report Number:
-
Resource Type:
-
Geographical Coverage:
-
TRIS Online Accession Number:00797077
-
Corporate Publisher:
-
Abstract:Flat and elongated particles have long been considered undesirable in hot mix asphalt (HMA) mixes due to their tendency to break down during construction and traffic. Currently, the Superpave mix design system currently specifies a maximum limit of 10 percent of flat and elongated particles at the 5:1 ratio for the design aggregate blend. Very few coarse aggregate stockpiles will fail the current 10 percent requirement at a 5:1 ratio. Hence, many agencies have expressed an interest in evaluating the particle shape at a more stringent 3:1 ratio. Before the specification is changed to a 3:1 ratio the effect of the particle shape on performance should be evaluated. Two aggregates (limestone and granite) were evaluated in their ?as-received? state and in two other particle shapes (more cubical, less F&E) obtained from Vertical Shaft Impact (VSI) crushing. The laboratory evaluation included volumetric mix designs, wheel tracking, fatigue testing, and aggregate breakdown determination. The results indicate that the particle shape of the aggregate may influence, to varying degrees, the coarse aggregate breakdown, the rutting susceptibility, and volumetric properties of compacted HMA mixes.
-
Format:
-
Collection(s):
-
Main Document Checksum:
-
Download URL:
-
File Type:
