RUTTING MEASUREMENTS OF HMA MIXTURES WITH THE ASPHALT PAVEMENT ANALYZER

This paper presents findings of a study conducted to examine the effectiveness of the Asphalt Pavement Analyzer (APA) in measuring permanent deformation characteristics of HMA mixes with different aggregate and binder types. The scope of this study included a 19-mm Superpave mix, 2 aggregate types (limestone and sandstone), and 4 asphalt binder types. The 4 types of asphalt binders were PG 64-22, an SB polymer-modified asphalt meeting PG 70-22, a gelled ,chemically modified asphalt meeting PG 70-22, and an SB polymer-modified asphalt meeting PG 76-22. Two performance tests were conducted: the APA rut test and the indirect tensile creep test, to evaluate the rutting susceptibility of the mixtures considered. Test results indicated that the APA was effective in characterizing rut-susceptibility of asphalt mixtures considered. The APA ranking of the test results was similar to the ones obtained from the indirect tensile creep test and from asphalt binder stiffness. Mixes with sandstone aggregate exhibited better rut-resistance than similar mixes with limestone aggregate.