Rest Period Effect on Asphaltic Damage

The effect of rest periods on asphaltic damage (fatigue or reflective cracking) is accounted by multiplying the shift factor SF in the damage equation with the following correction factor:

where   Rp is the rest period,

             Tref and aT are master curve parameters,

   h(t) is the viscosity at a temperature of T, and

   h(T_ref) is the viscosity at reference temperature T_ref, and

   Rpref and j are constants.

The default values of Rpref and j are 10 sec and 0.4, respectively. The rest period is calculated as the interval between trucks (not axles) by evenly distributing the trucks over time.