Oxidative aging of asphalt rubber and implications to performance analysis

Crumb rubber modified asphalt (CRMA) may be used to obtain improved asphalt Superpave grade as well as adhesion. Though tests indicate that CRMA may have improved grade, the results are suspect because of the failure of PAV aging to simulate road aging Unmodified asphalts show a constant relation between viscosity change and growth of the infrared carbonyl peak This relation, called the hardening susceptibility (HS), is independent of oxidation temperature below 100C for unmodified asphalt. For CRMA, this property is very dependent on oxidation temperature and pressure with hardening in the PAV significantly less than at road conditions for the same carbonyl change. Even so, CRMA generally does harden less at road conditions than unmodified asphalt The dependence of HS and hardening rate at 60C and one atmosphere (assumed to simulate road hardening) depends on the amount of rubber and the blending conditions.

Oxidative aging of asphalt rubber and implications to performance analysis Academic Article