Section 4138.  Cutback and Liquid Asphalts

4138.01      general requirements.

A.    Use the grade specified. Meet the following requirements:

· Rapid Curing (RC)       AASHTO M 81

· Medium Curing (MC)   AASHTO M 82

· Slow Curing (SC)         AASHTO M 140 ASTM D 2026

B.    The spot test indicated in AASHTO M 81, M 82, and M 140 will not be required.

C.    When using antistrip additive with cutback asphalt, (as required in Article 2307.02, B, 2 or when specified otherwise) use an additive approved according to Materials I.M. 491.16. Add at the approved dosage rate. Ensure the treated cutback asphalt produces a positive result when tested according to Iowa DOT Materials Laboratory Test Method No. 629.

D.    In Table 1 of AASHTO M 81, the distillation test requirements are as follows:

Distillate, by volume to 374°F, to be a minimum of 4% of the total distillate to 680°F.