This paper compares in-situ (field) aged road bitumen and fresh paving grade bitumen by presenting various rheological measurements conducted with Dynamic Shear Rheometer (DSR). Performed tests included strain sweeps, frequency sweeps and shear rate sweeps in the linear and nonlinear viscoelastic region of response at temperatures ranging from 2 to 120°C. Some fundamental rheological concepts were utilised to explain the origins of observations employing colloidal model describing bitumen structure. However, additional testing, including chemical analysis techniques like GPC and IR, is needed to validate and maximise output from this single equipment analysis. Testing suggests that Lissa-jous figures from strain sweep tests could be used to characterise cracking propensity of binders; research revealed ductile like behaviour for aged bitumen in the nonlinear region, which is postulated here to originate from the formation of crazes (microcracks) capable of load transfer.
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