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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]

Evaluation of pavement performance along with proper maintenance and rehabilitation (M&R) activities as well as application of high quality construction materials can prevent premature failures in road networks and supply safety and convenience for road users. Moisture damage is one of the most common modes of failures in flexible pavements which can expedite other forms of failures in pavements. By using anti-stripping agents, the strength of bituminous mixtures against moisture damage increases. The objective of this research is to assess and compare the effects of Evonik, as a newly introduced material, Zycotherm as a common nanomaterial and hydrated lime on the moisture susceptibility and other performance characteristics of asphalt mixtures. Moisture susceptibility of these mixtures was investigated using the indirect tensile strength (modified Lottman) and Texas Boiling tests. Other performance characteristics were evaluated by means of Marshall, Resilient Modulus and Dynamic Creep tests. Results showed that all three additives can enhance the moisture resistance of asphalt mixtures and the mixture containing 0.1 percent of Zycotherm had the best performance. The hydrated lime had the best impact in increasing the rutting resistance of asphalt mixtures due to the hardening effect on the mixtures. [ABSTRACT FROM AUTHOR]