PHASE II REPORT - Caltrans

3.7.6 Step 6: Evaluate the Long Term Properties of the Mixture
This step consists of evaluating the following:
• Abrasion: Using the CAT
• Water Resistance: Using the CAT
• Deformation (rut-filling mixes only): TB-109
Finally, any necessary adjustments and recheck of the mixing indices (spreadability, traffic, and
24 hour cohesion) will be made.
After selecting the best mix from the short-term test methods noted above, the mix will be tested
for the following long-term performance properties:
• Abrasion resistance
• Water resistance
• Deformation
3.7.6.1 Abrasion Resistance
This property will be measured using the CAT test using fully cured specimens, soaked for 6
days, under project specific environmental conditions.
3.7.6.2 Water Resistance
The CAT abrasion test will be run on the final mix design after being soaked for 6 days at a
temperature of 77°F (25°C) and comparing the loss to that of a 1-hour soak and express this as
a ratio. This information will be compared to the results of an existing mixture in order to
determine the appropriate specification limits. The test will then be checked with a mix of known
standard properties using other materials with which the team and advisory group have
experience.
3.7.6.3 Deformation
This property will be measured using TB-109 “Excess Asphalt by LWT Sand Adhesion”.
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