Creep Properties of Asphalt Binder, Asphalt Mastic and Asphalt Mixture

For designing asphalt materials resistant to permanent deformation and rutting, a low creep deformation at high temperature is the crucial performance property. Usually, creep deformation is assessed through static or cyclic compression tests at elevated temperature, both for asphalt mixtures as well as for asphalt binders. For asphalt mixtures, static and cyclic compression tests are specified in the European Technical Standards. For asphalt binders, creep tests are usually performed by means of a Dynamic Shear Rheometer (DSR), such as Multiple Stress Creep and Recovery Test (MSCRT) developed for Polymer-modified asphalt binders. However, different author questioned the control parameters and significance of the MSCRT, especially for plain asphalt binders. In this paper, creep properties of asphalt binders and asphalt mastics (binder-filler-mixtures) are tested in the DSR using increased loading and recovery times to ensure steady-state flow conditions. These tests are performed on a set of 10 different asphalt binders and 18 corresponding asphalt mastics. The same material combinations are used in asphalt mixtures produced in the laboratory and then subjected to a cyclic compression test to assess the creep properties of the asphalt mixture. Finally, the creep properties resulting from asphalt binder tests, asphalt mastic tests, and asphalt mixture tests are correlated. The results show reasonable correlations over the different scales. It is concluded, that the asphalt binder has a significant impact on the creep behavior of the corresponding asphalt mixture.