DETERMINING THE RHEOLOGICAL PROPERTIES OF ASPHALT BINDER USING DYNAMIC SHEAR RHEOMETER (DSR) FOR SELECTED PAVEMENT STRETCHES

Abstract

This paper aims to study the rheological properties of the binder taken from four years old flexible pavement stretch. The stretch was divided into six different sections based on the thickness of the surface course. Originally, 60/70 grade asphalt binder was used throughout the pavement stretch. The binder was obtained from the process of extraction and recovery. Dynamic shear rheometer (DSR) test was conducted on the recovered asphalt binder to determine the various parameters viz., Complex modulus G * , Elastic and viscous modulus, Complex viscosity and the phase angle δ. The major pavement distress modes namely, rutting and fatigue cracking were addressed by these output parameters of DSR. Rutting is caused by permanent deformation of paving mix while fatigue is related to the energy absorbed during repeated load application to pavement. The test results indicated that the 60/70 binder extracted from the selected stretches were stiff enough to resist rutting and fatigue failure.