Evaluation of the Rheological Properties and Master Curve Development for Bituminous Binders Used in Roofing

As dynamic shear rheology (DSR) testing of asphalt binders is becoming the primary mode to evaluate asphalt binders worldwide, an understanding of the rheological performance of asphalt binders has become increasingly important. Such understanding of the basic principles of rheology is essential for those developing and applying specifications, as well as developers and producers of new and enhanced roofing binders. This paper discusses the determination of the complex shear (stiffness) modulus (G*) and phase angle (δ) of bituminous binders over a range of temperatures and frequencies when tested in harmonic sinusoidal oscillatory shear mode using a dynamic shear rheometer (DSR) with parallel plate test geometry where both plates are controlled at the same temperature. Rheological measurements and master curves for six different binders used in the manufacture of industrial roofing materials are presented. The data presented are results of testing of unaged and oven-aged binders to include a standard air blown binder, a catalytically air blown binder, and various modified bitumen binders.