عنوان مقاله [English]
Bitumen aging is an irreversible process that reduces deformability and increases hardening and stiffness. Aging process is due to changes in type and size of very widely and different molecules of asphalt cement. It is considerable at two stages: short-term aging and long-term aging. In this paper a regression model is proposed based on LTPP data to predict complex shear modulus (G*) and phase angle (δ) of bitumen during service time. This model is prepared from ten different types of bitumen data. Using proposed model, by just one DSR test on origin bitumen at a temperature, we can determine DSR results on aged bitumen at each time and each temperature. Model show the most effective time for aging process is earliest three years. Hardening due to aging at temperature under 25oc is clearly but at upper temperature there is no significant different between original and aged bitumen. The model accuracy for prediction of long term bitumen performance and for use in pavement distress models is in good.