How good are linear viscoelastic properties of asphalt binder to predict rutting and fatigue cracking?

This article evaluates the effects of linear viscoelastic properties of asphalt on pavement rutting and fatigue cracking. The parameters in the binder specification recently developed by the Strategic Highway Research Program (SHRP) were also compared for pavement performance. Two studies were conducted for asphalt-aggregate mixes. The first study was the wheel tracking test to evaluate the rutting of mixes containing three asphalts. The second study was a detailed field study of the effects of binder properties on the pavement performance of eight different sections. Results of both investigations indicated that SHRP parameters were not sufficient indicators for predicting the rutting and fatigue cracking of pavements. The discrepancies between performance data and existing parameters of the binder mainly resulted from the inherited assumptions made during the specification development, that is, stress- or strain-controlled mode and traffic loading frequency. In order to directly relate the linear viscoelastic properties of asphalt binders to pavement performance, calculating the dissipated energy per traffic cycle, W_d, became imperative. Fundamental derivation of W_d was developed in this study. Results indicated that W_d could predict the rutting and fatigue cracking of pavements reasonably well. This study, proposed the dissipated energy, W_d, as the single parameter for evaluating pavement rutting and fatigue cracking.