Abstract
The authors used 9 asphalts oxidized at various temperatures and pressures to determine the hardening kinetics for the DSR function, an easily measured and meaningful surrogate for 15°C ductility that relates well to age-related binder deterioration. For each asphalt, there is a rapid initial period that slows to a constant rate period. This constant rate period can be represented by carbonyl formation (oxidation) rate times a hardening susceptibility (HS). For the DSR function and viscosity, the HS and initial jump were pressure- but not temperature-dependent. The DSR function initial jump was relatively higher than the viscosity initial jump.