New polymer-modified bituminous binders require verification of the relationship between binder properties and road pavement performance, formerly found for conventional road bitumens. The paper deals with one particular problem of polymer-bitumen (PB) viscosity and bituminous mixture rutting resistance. Non-Newtonian, shear-dependent behaviour of PB in a viscosity measurement has been characterized by a new equation proposed by the author. This equation enables calculation of the absolute (zero shear rate) viscosity of PB and is applied for evaluation of test results at 60 and 90-degrees-C. The absolute viscosity of PB at 60-degrees-C has been correlated with the bituminous mixture's rutting resistance at 45-degrees-C. Correlation with other rheological properties of PB is also examined by means of multiple regression analysis.
