4137.01
GENERAL REQUIREMENTS.
A.
Meet the requirements for the type and grade specified in the contract documents and comply with the Combined States Binder Group.
B.
Determine performance grade according to AASHTO R 29.
C.
Polyphosphoric Acid may be used as a co-modifier up to 0.5% by weight of binder. The Engineer may verify with laboratory testing.
D.
Except for Standard Traffic grades, meet CSBG requirements for Minimum Percent Recovery when tested per AASHTO T 350 at the high temperature identified by the PG grade.
E.
Waive stress sensitivity limits (Jnr Diff) for AASHTO M 332 when Jnr at 3.2 kPa is below 0.5 kPa-1.
F.
When PG 58-34E+ is specified, the binder shall comply with requirements of PG 58-34E except that a minimum percent recovery of 90% when tested at 58°C per AASHTO T 350 at 3.2 kPa is required.
PG 64-34E except that a minimum percent recovery of 90% when tested at 64°C per AASHTO T 350 at 3.2 kPa is required.
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