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The asphalt mixtures are composed of aggregates and asphalt used in the construction of the majority of roads. In order to ensure the sustainability of the infrastructures, the evaluation of the quality and the performances of these materials are essential. In this context, several researches have been focused on the development of predictive models, often empirical ones, in order to deduce the viscoelastic properties of an asphalt mixture based on the properties of its constituents (binder and/or aggregate). In this context, we suggest a homogenization model based on the generalized self-consistent scheme (GSC) to predict the complex module of the asphalt concrete from the properties of its components. In the aim of the approach validation, different types of mixtures (hot and warm) made in the laboratory were tested. The results showed that one can predict the complex modulus of the different types of asphalt concretes for temperatures less than 20 °C. However, beyond this temperature, the precision of the model decreases. Besides, the comparison of the micromechanical model with the rheologic models in literature showed that the suggested model can be also relevant in terms of predictions as the considered models. [ABSTRACT FROM AUTHOR]

Fatigue is considered the main damaging phenomenon at « average » temperature in flexible pavement structures. A fatigue damage model is thus the first step in applying a mechanistic-empirical approach to sizing. This paper highlights the main elements of fatigue models in order to thoroughly understand the various calculation tools available for a mechanistic-empirical sizing application. The signification of the various coefficients of the models is described and interrelations are established. An analysis is proposed to improve the representativeness of the fatigue life span law of the material. All calculation tools for mechanistic-empirical sizing use the Wöhler fatigue curve. Both fatigue curve coefficients are at the core of the models and describe the specific performance of the tested bituminous material families. Processing the results of a classic fatigue test to exclude biased effects will substantially modify the values of these two coefficients. It is demonstrated that the life spans determined from raw results are overestimated. [ABSTRACT FROM AUTHOR]