The development of a performance based specification for all bituminous binders has been the objective of an Austroads binder research program. A key component of that program has been the identification of a robust property capable of defining the low temperature fatigue characteristics of this diverse range of materials. The first stage identified a strong relationship between the low temperature viscosity (extensional viscosity) of all bitumens, multigrade bitumens and many polymer modified binders (PMB) and their contribution to the fatigue performance of a series of asphalt mixes prepared from these binders. This paper presents the second and closing step in the achievement of a comprehensive binder fatigue property for all bitumens multigrade bitumens and PMBs. The key to this task has been the identification of the role of each binders breaking or failure stress and the relationship between this property and the binders extensional viscosity. The identification of this property will allow a binder durability test to be developed for all bituminous binders including bitumens, multigrade bitumens and PMBs. This property will allow the long term performance of these binders to be assessed and contribute to specification control of the long term serviceability where asphalt fatigue is a critical performance issue. (a) For the covering entry of this conference, please see ITRD abstract no. 0612AR242E.
Samenvatting