aggregate shape on base behavior. Transportation
course materials be simple and quick to use.
Research Record 1227, p. 171182.
Either the flow coefficient or the uncompacted
void tests have the greatest potential to meet the
Bikerman, J.J. (1964) Adhesion of asphalt to stone.
above requirements. Currently, these tests are
MIT Civil Engineering, Research Report R64-3.
limited to aggregates with a maximum size of 20
Bindra, S.P., and H.A. Al-Sanad (1983) Particle
mm, and modifications to both the equipment
index evaluation of aggregates for unbound pav-
and test procedures are required. It is recom-
ing mixtures. In Proceedings of the Fourth Confer-
mended that a research program be conducted to
ence of Road Engineering, 2226 August. Jakarta,
develop an index test for angularity of aggregates
Indonesia: Road Engineering Association of Asia
to a maximum size of 50 mm using both the flow
and Australasia, p. 8593.
coefficient and the uncompacted void tests. The
British Standards Institution (1975) BS 812: Test-
results from both these tests will be correlated
ing Aggregates.
with the particle index, because this index has
Gupta, R.D. (1985) Effect of size of particles on
been developed for larger size aggregates.
their angularity. Journal of the Institution of Engi-
It is also advisable, but optional, that the
neers (India), 65(CI 5): 210214.
shape, angularity, and surface texture of the
Holubec, I., and K.H. Wilson (1970) A cyclic creep
aggregates be characterized using the techniques
study of pavement materials. Final Report, De-
developed in the geological arena. These will be
partment of Civil Engineering, University of
used to calibrate the index results obtained from
Waterloo, Ontario, D.H.O. Report No. RR163.
the flow coefficient and the uncompacted void
Holtz, R.D., and W.D. Kovacs (1981) An Introduc-
tests using a similar method developed by Barks-
tion to Geotechnical Engineering. Englewood Cliffs,
dale and Itani (1994). The geological characteriza-
New Jersey: Prentice-Hall, Inc.
tion can also be used to correlate resilient modu-
Huang, E.Y. (1962) A test for evaluating the geo-
lus and shear strength test results using a similar
metric characteristics of coarse aggregate parti-
approach used by Barksdale and Itani (1994)
cles. Proceedings, American Society for Testing and
again.
Materials, 62: 12231242.
The index angularity measurements need to be
Huang, E.Y. (1965) An improved particle index
tied to the resilient and strength properties of the
test for the evaluation of geometric characteristics
aggregates. Ideally, the resilient modulus and
of aggregate. Michigan Highway Research Pro-
ject No. 86546.
shear strength tests should be conducted under
Ishai, I., and H. Gelber (1982) Effect of geometric
optimum moisture and saturated conditions. The
irregularity of aggregates on the properties and
critical time for the base courses in seasonal frost
behavior of bituminous concrete. Proceedings, As-
areas is during spring thaw. Therefore as a mini-
sociation of Asphalt Paving Technologists, 51: 494
mum it is recommended that the tests be con-
521.
ducted on saturated samples under undrained
Ishai, I., and E. Tons (1971) Aggregate factors in
conditions. As a corollary to the testing program,
bituminous mixture designs. University of Mich-
moisture density relationships will be developed
igan, Ann Arbor, Report 335140-1-F.
using the large-scale Proctor testing device. These
Ishai, I., and E. Tons (1977) Concept and test
relationships will be compared with those
method for a unified characterization of the geo-
obtained from standard testing procedures used
at VAOT.
metric irregularity of aggregate particles. Journal
of Testing and Evaluation, 5(1): 315.
Krumbein, W.C. (1941) Measurement and geolog-
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ASTM D 2488-90 (1996) Standard practice for de-
shape and its influence in engineering materials.
scription and identification of soils (visual-manual
Journal of the British Granite and Whinestone Federa-
procedure). ASTM, vol. 04.08, Soil and Rock.
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ASTM D 3398-93 (1996) Standard test method for
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index of aggregate particle shape and texture.
Hiltunen, and S.M. Stoffel (1993) Development
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Barksdale, R.D., and S.Y. Itani (1994) Influence of
and specifications for asphalt binders and paving
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