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• Load-CMOD response of asphalt mixtures is obtained by means of CZM simulations • Crack growth under mixed mode loading and viscoelastic behavior of the material. • Effects of mixture's constituents on crack propagation mechanism were investigated. This paper discusses the effects of mixed mode loading on cohesive zone parameters obtained from load-crack mouth opening displacement (CMOD) curves in asphalt mixtures at intermediate temperature. To this end, a coupled viscoelastic numerical-experimental approach has been used to capture the cohesive strength and fracture energy in the fracture process zone utilizing asymmetric semi-circular bending test. Three mode mixities (i) pure mode I (ii) mixed mode I/II with higher fraction of tensile deformation and (iii) mixed mode I/II with higher fraction of shear mode were tested and simulated. The load-CMOD curves for the investigated mode mixities and for different asphalt mixtures were predicted successfully using the aforementioned computational framework. The results showed that the binder type and loading mode have significant effect on both cohesive strength and cohesive fracture energy values of asphalt mixtures. Aggregate gradation was only effective on the cohesive strength values. Considering the interactions of the mixtures' constituents and loading, the binder- loading mode and binder-aggregate gradation were significantly effective only on cohesive fracture energy. The stiffer an asphalt binder, the more cohesive strength and fracture energy values were observed. Decreasing the distance between the supports which is equivalent to higher fraction of the shear mode in the ASCB test contributes to greater cohesive fracture energy. [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]