Details:

Creators:
Kandhal, Prithvi S. ; Brown, E.R.
Kandhal, Prithvi S. ; Brown, E.R. Less -
Subject/TRT Terms:
[+]
Aggregates, Rock And Stone Asphalt Mixtures Binder Content Gyratory Testing Machines (GTM) Marshall Mix Design Method Test Procedures
DOI:
https://doi.org/10.21949/1404492
Resource Type:
Tech Report
TRIS Online Accession Number:
00625354
Corporate Publisher:
National Center for Asphalt Technology (U.S.)
NTL Classification:
NTL-HIGHWAY/ROAD TRANSPORTATION-Materials;NTL-HIGHWAY/ROAD TRANSPORTATION-Pavement Management and Performance;
Abstract:
Increased incidence of premature rutting of heavy duty asphalt pavements has

been experienced in recent years. There is a general agreement among most

asphalt paving technologists that the use of large size stone in the binder and

base courses will minimize or eliminate the rutting of heavy duty-pavements.

However, the wide acceptance of the Marshall and Hveem mix design procedures

inhibits the use of large stone mixes because these methods use standard 4-inch

(101.6 mm) diameter specimens and limit the maximum aggregate size to one inch

(25.4 mm).

Modified Marshall equipment and Gyratory Testing Machine (GTM) are now available

for compacting and testing 6-inch (152.4 mm) diameter specimens to accommodate

aggregate up to 2-inch (50.8 mm) maximum size. However, some agencies continue

to use 4-inch diameter specimens for mixes containing 1&1/2inch (38.1 mm)

maximum size aggregate. This study compares the mix properties such as Marshall

stability and flow, indirect tensile strength, and permanent deformation (from

static creep test) obtained on 4-inch and 6-inch (101.6 and 152.4 mm) diameter

specimens. Both Modified Marshall and GTM equipment were used to compact the

specimens of these two sizes. The maximum aggregate size ranged from 1/2 to

l&1/2-inches (12.5 to 38.1 mm).

The test data indicates increased coefficient of variation when testing 4-inch

(101.6 mm) specimens of the mix containing aggregate larger than one inch

(25.4 mm) compared to 6-inch (152.4 mm) specimens. The 6-inch (152.4 mm)

diameter specimens also had lower variability in creep test compared to 4-inch

(101.6 mm) specimens. Laboratory and rationally derived data indicating the

ratios by which stability and flow values increased is also given in the paper.

It has been recommended to use 6-inch (152.4 mm) diameter specimens for large

stone asphalt mixes.


Format:
PDF
Collection(s):
US Transportation Collection
Main Document Checksum:
[+]
urn:sha256:3e4b3863289d6b290ae490db4e644eaf42f429bb0f3d644fa77d5cd2acc4562a
Download URL:
https://rosap.ntl.bts.gov/view/dot/13187/dot_13187_DS1.pdf
File Type:

Supporting Files

• No Additional Files

More +