Evaluation of the durability of asphalt mixtures depending on the physical properties of aggregates

This study aims to assess the durability of asphalt mixtures through their performance versus damage by aging and water sensibility, depending on the physical properties of aggregates. Twelve types of asphalt mixtures were analyzed, using 3 types of aggregates (different shape and mineralogy), and 4 types of asphalt binders (2 conventional, 1 high modulus and 1 modified). The characterization of the aggregates is carried out following the protocol proposed by Zingg and the particle index (PI) according to ASTM-D3398. Both parameters have been correlated with the performance of the aggregate in the mixture. The performance of the mixtures is analyzed by the parameters of FENIX test, such as peak tensile load, stiffness rate and deformation capacity in 3 aging conditions and under wet conditions. The water sensitivity was also evaluated according to the UNE-EN12697-12. The results show that the physical characterization of the aggregates through Zingg method is not enough to predict the behavior of the mixtures studied because it considers only the coarse fraction. In turn, the results show that the angularity and surface texture of the fine fraction aggregates, analyzed through the PI parameter, has a significant effect on the performance versus moisture damage and aging of the asphalt mixtures tested.