Summary of Rubber Modified Asphalt Product Specifications around ...

Agencies Source Gradation Additives Other Notes
New Jersey DOT CRM shall be
ambient ground,
free of wire or
other
contaminating
materials.
Scrap tire or
shredded tire
from autos,
trucks, or other
equipment in
USA
Massachusetts
DOT
Jiangsu Province,
China
Granulated
rubber from a
vulcanized
rubber product
from ambient
temperature
processing.
Free of wire or
other
contaminating
materials. Fiber
should be less
than 0.5%.
3.2 Rubberized Asphalt Cement
Crumb Rubber
Gradation:
#8:2.36 mm (100)
#16:1.18 mm (65-100)
#30:600 um (20-100)
#50:300 um (0-45)
#200:75 um (0-5)
Gradation:
#8:2.36 mm (100)
#10: 2.00 mm (95-100)
#16: -
#30:600 um (0-10)
#50:300 um (0-5)
Crumb Rubber
Gradation:
#10:2.00 mm (100)
#16:1.18 mm (65-100)
#30:600 um (20-100)
#50:300 um (0-45)
#200:75 um (0-5)
Add up to
4%
calcium
carbonate
to prevent
the
particles
from
sticking
together.
Moisture
content:
maximum
0.75%
Density:
1.15
0.05
g/cm 3
4%
calcium
carbonate
Density:
1.15
0.05
g/cm 3
4%
calcium
carbonate
In Ontario, asphalt rubber is called rubberized asphalt cement. It should be produced as a Type
III asphalt rubber binder, according to ASTM 6114, which is suitable for cold regions. Table 2
summarizes the binder and CRM blending temperature and other requirements during the asphalt
rubber binder production.
The CRM content of the rubberized asphalt cement used by different agencies is different, but
typically follows ASTM asphalt rubber standard of more than 15% by weight of the binder.
California, Arizona, and Massachusetts use more than 20%, while Texas and New Jersey use less
than 20%. Ontario, Canada uses 18-20% of CRM in its rubberized asphalt cement.
The blending temperatures used by different agencies vary, ranging from 165 – 226 o C (330 –
440 o F). Ontario’s specifications only mentioned the blending temperature. California, Arizona,
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