consistency in fabricating laboratory specimens,
(1982), appears to be a quick and simple approach
and it would measure an important response
to indexing aggregates based on propensity to
mechanism of aggregate to freezing. Sneck et al.
expand during freezing.
(1972) and Davison (1982) describe such a test.
They placed rock particles into a glass container
LITERATURE CITED
fitted with a calibrated tube and filled with alco-
hol, and they observed that the volume of alcohol
AASHTO T 85-85 (1998) Specific Gravity and
abruptly changed each time the container was
Absorption of Coarse Aggregate. Washington D.C.:
cooled below the freezing point of water. It does
American Association of State Highway Trans-
not appear that this test was pursued any further.
portation Officials.
Another variation is to consider freezing aggre-
AASHTO T 96-94 (1998) Standard Test Method for
gate in alcohol while it is suspended from a scale.
Resistance to Degradation of Small Size Coarse Aggre-
Any volume change should be noted as a change
gate by Abrasion and Impact in the Los Angeles
in weight.
Machine.Washington, D.C.: American Association
of Highway Transportation Officials.
AASHTO T 103-83 (1990) Standard Method of Test
SUMMARY AND RECOMMENDATIONS
for Soundness of Aggregates by Freezing and Thaw-
Hot-mix asphalt aggregates play a significant
ing. Washington D.C.: American Association of
role in controlling pavement distresses such as
State Highway Transportation Officials.
rutting, skid resistance, and freezethaw deteriora-
AASHTO T 104-86 (1990) Standard Method of Test
tion. This report provides a state-of-the-art sum-
for Soundness of Aggregate by Use of Sodium Sulfate
mary of existing and new, promising laboratory
or Magnesium Sulfate. Washington D.C.: American
test methods and devices for characterizing the
Association of State Highway Transportation
aggregate.
Officials.
Several laboratory tests for rutting were identi-
Aldrich, A.C. (1996) Influence of aggregates gra-
fied, ranging from sophisticated image analysis
dation and particle shape/texture on pavement
to determination of flow time of aggregates. The
deformation of hot-mix asphalt pavements. U.S.
NAA uncompacted void value test appears to be
Army Corps of Engineers, Waterways Experiment
simple and has been found to correlate well with
Station, Technical Report GL-96-1.
ASTM C 88-76 (1981) Standard Test Method for
aggregate shape, angularity, and texture. The
Soundness of Aggregates by Use of Sodium Sulfate or
flow time index method used by the Quebec Min-
Magnesium Sulfate. Annual Book of ASTM Stan-
istry of Transportation also appears to show great
dards, Part 14. Philadelphia: American Society for
promise as a simple tool for evaluating the same
Testing and Materials.
properties.
ASTM C 127-88 (1995) Standard Test Method for
The macro- and microtexture of the pavement
Specific Gravity and Absorption of Coarse Aggregate.
surface appears to control the skid resistance of
Annual Book of ASTM Standards, Part 14. Phila-
the pavement surface. The sand patch test is com-
delphia: American Society for Testing and Mate-
monly used to characterize the macrotexture of
rials.
the pavement surface.
ASTM C 666-84 (1990) Standard Test Method for
The frictional properties of microstructure are
Resistance of Concrete to Rapid Freezing and Thawing.
determined using frictional testers. The most com-
Annual Book of ASTM Standards, Part 14. Philadel-
mon one is the British skid resistance tester. The
phia: American Society for Testing and Materials.
wear and polishing characteristics of the aggre-
ASTM C 671-77 (1981) Standard Test Method for
gates can be determined by several wheel polish-
Critical Dilation of Concrete Specimens Subjected to
ing devices. Quebec MOT uses high-pressure
Freezing. Annual Book of ASTM Standards, Part
water projection to conduct accelerated polish-
14. Philadelphia: American Society for Testing
ing, and friction results from the test appear to
and Materials.
correspond well to those obtained from the Brit-
ASTM C 1252-93 (1995) Standard Test Methods for
ish pendulum number.
Uncompacted Void Content of Fine Aggregate (as In-
For freezethaw durability, aggregate expan-
fluenced by Particle Shape, Surface Texture, and Grad-
sion was identified as the major contributor to
ing). Annual Book of ASTM Standards, Part 14.
pavement frost damage. A variation to the expan-
Philadelphia: American Society for Testing and
sion measurement of unconfined aggregate
Materials.
described by Sneck et al. (1972) and Davison
20
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