Historically, empirical binder properties have been used to provide an indication of the performance of asphalt mixes. With the advent of higher axle loads and increasing traffic densities, the use of polymer modified bitumens (PMBs) and other speciality binders is increasing. These binders often have significantly different rheological properties to unmodified bitumens. As a result, conventional binder properties and correlations with asphalt performance may not be valid. In recognition of this, BP has investigated the use of binder rheological measurements to predict asphalt pavement performance including: (1) Pavement deformation (rutting) at high service temperatures; (2) Fatigue at intermediate service temperatures; (3) Brittle fracture at low service temperatures. Rheological parameters are identified which may be used to predict mix performance at high and low temperature. Fatigue is more complex and binder rheology alone is shown to be insufficient to predict this. The importance of selecting the correct measurement conditions is also discussed. (A)
Samenvatting