Rheological Properties of Mineral Filler-Asphalt Mastics and Its Importance to Pavement Performance

The rheological and failure properties of eight asphalt-filler mastics were characterized using new testing techniques being developed within the SHRP program for testing asphalt binders. The mastics were prepared using four SHRP core asphalts and two fillers (calcite and quartz). The rheological measurements were used to construct rheological master curves and temperature shift functions. The failure properties were measured at different temperatures and strain rates and were shifted using time- temperature superposition to construct stress and strain-to- failure master curves. A subset of the mastics was also tested after oxidative aging with the pressure aging vessel (PAV) and after isothermal aging at low temperatures. The properties of the mastics were compared with the asphalt binder properties to describe the changes resulting from adding the fillers. The fillers were found to change the shape of the rheological master curves and to significantly increase the failure stress at all combinations of temperatures and loading times. The effects of mineral fillers upon relative stiffness, oxidative aging, hardening, low temperature cracking fatigue and rutting resistance are discussed. For the covering abstract see IRRD 858225.