DYNAMIC-MECHANICAL CHARACTERIZATION OF BINDER AND ASPHALT CONCRETE

The dynamic-mechanical analysis (DMA) is a powerful tool to investigate the rheological behaviour of materials. This technique is widely used to predict the end product performances starting from raw material properties. The aim of this work is to investigate how the binder type, SBS-modified or unmodified bitumen, can affect the asphalt concrete performances. The DMA has been used to evaluate both, binder and concrete, rheological characteristics in a wide range of temperatures and frequenices. Unfortunately even up-to-date experimental devices cannot cover the whole range of interest. Adopting time-temperature superposition principle master curves can be obtained and performances can be predicted in a wider range of service conditions. In this work a satisfying correlation between binder and dense graded concrete dynamic parameters is reported. The data show that adopting the same grading curve the properties of neat and SBS-modified bitumen are transferred to the concrete mix. Moreover separating the complex modulus in its viscous and elastic components, it is possible to highlight the mechanisms that contribute to the final concrete mechanical behaviour. (A) For the covering abstract see IRRD 885061.