Modelling rheological characteristics of rejuvenated aged bitumen

The present study reports on rheological properties of rejuvenated non-aged and aged bitumen samples with a pyrolytic product (PP) as a rejuvenator. Various experimental and numerical methods were used in order to investigate the addition of various concentrations of PP to aged and non-aged bitumen samples. It was confirmed that the application of PP as a rejuvenator to the aged bitumen has been successful. The main focus of the study was on the use of several mathematical and mechanical models, which would successfully describe and predict experimental results. Precise calculations for the complex modulus were obtained by generalised five-parameter Sigmoidal model, while the Al-Qadi model enabled good predictions for the phase angle estimations. However, better predictions of rheological parameters were obtained for non-aged bitumen. The results confirmed the possibility of using the prediction models for the estimation of various rheological properties of aged and non-aged bitumen samples with the addition of rejuvenator.