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This study deals with the trends of fatigue life between asphalt binders and mixtures using the rate of dissipated energy change (RDEC) approach. To this end, the time sweep and four-point beam fatigue tests were utilized to assess the fatigue life of bituminous materials under different strain amplitudes. The results indicated that the RDEC approach can be utilized as asphalt mix fatigue estimation in terms of asphalt binder fatigue life. A separate unique relationship exists between the fatigue life of asphalt materials and their plateau value (PV) covering different types of materials and strain levels. Furthermore, a fatigue model was developed based solely on the PV values of asphalt binders and mixtures including all the materials and the strain levels used in this study. Results revealed conformity between time sweep and four-point beam fatigue tests in terms of RDEC methodology, and a strong correlation exists between these two fatigue tests. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

In this paper dissipated energy (DE) versus loading cycles is plotted, at the same time fatigue life of asphalt binders were investigated using of dissipated energy (DE) approach and based on linear and nonlinear strain levels. It was found that based on results obtained of time sweep test; there is a fair correlation between dissipated energy at the 50th loading cycle and fatigue life of asphalt binders in all strain levels. As a result, initial dissipated energy (IDE) is a parameter obtained from time sweep test, so the amount of initial dissipated energy (IDE) at the 50th loading cycle can be predicted the fatigue of asphalt binders without performing millions of loading cycles. [ABSTRACT FROM AUTHOR]

The present research study addresses the fatigue life of different asphalt mixtures by means of 4PBF test. To this end, the fatigue behavior of unmodified asphalt mixtures and modified mixtures with styrene-butadiene-styrene polymer and crumb rubber as modifier were investigated in low and medium strain levels. Results showed that there is an excellent correlation between the fatigue lives of different asphalt mixtures in terms of the dissipated energy approach. It can be observed from result that the amount of initial dissipated energy at the 50th loading cycle predicted the fatigue life of asphalt mixtures without performing millions of loading cycles. Furthermore, the initial dissipated approach provides more reliable results from fatigue life of asphalt mixtures in comparison to the traditional fatigue tests. [ABSTRACT FROM PUBLISHER]