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Film thickness describes the coating around aggregate particles on asphalt mixtures. The standard method of calculating film thickness has proven to present several limitations, such as assuming an average thickness independent of particle size, being completely independent to the porosity of the mixture and considering only one mineral type. In this paper, a binder distribution model is developed for aggregates according to size and role in the structure. The aggregates are separated into two different structures: primary structure, the load bearing one, and secondary structure, smaller material that provides stability to the skeleton. A coating thickness for these two structures is calculated from a geometrical consideration that includes the packing arrangement of particles and the effect of overlapping as the film grows. The results were compared with known rutting performance of field mixtures and moisture conditioned laboratory mixtures, showing a good correlation between film thickness and resistance to failure. [ABSTRACT FROM AUTHOR]

Highlights: [•] Asphalt mixture low temperature cracking performance has investigated. [•] A new thermal cracking model was proposed. [•] The effect of non-linear thermal contraction coefficient was investigated. [•] The importance of cooling rate and creep compliance parameters was studied. [•] This extended model can evaluate the low temperature cracking performance. [ABSTRACT FROM AUTHOR]

Abstract: Sufficient coating, easy paving and good compaction are desirable parameters, which are approachable with the optimum viscosity of the mastic. In many studies, models have been developed for calculating the viscosity for different types of suspensions at various particle-to-fluid ratios. Unfortunately, none of them are applicable to asphalt mastics, since this material has a much wider range of mineral filler concentration from dilute to very concentrate. To give an overview of the existing viscosity models and to evaluate their range of applicability to asphalt mastics, an extensive literature review was performed. A new empirical framework was developed that removes some of the stipulated limitations of the existing theories. [Copyright &y& Elsevier]