Asphalt fatigue modeling in constant strain time sweep tests based on dissipated energy approaches

This paper aims to develop asphalt binder fatigue models by time sweep tests under constant strain. By investigating the fatigue life in neat and modified asphalts under linear and nonlinear viscoelastic responses, results were analyzed in terms of strain levels, asphalt type, and additive content. The dissipated energy and dissipated energy ratio concepts were utilized to develop the phenomenological models for estimating fatigue lives of asphalt binders. Results showed that the dissipated energy ratio-based equations give relatively identical fatigue models irrespective of the strain level or asphalt binder type. Moreover, statistical analyses were performed to investigate the contribution of each parameter in the fatigue model prediction. A comparison was made between fatigue life predictions by means of traditional and energy-based methods. Results proved that the fatigue life prediction models based on the concept of dissipated energy ratio follow a similar trend.