Research into effect of asphalt mixture aging on stiffness

Abstract

The paper focuses on the research of the stiffness of asphalt mixtures exposed to short-term and long-term aging. Asphalt mixtures are exposed to this type of ageing during their production, laying and compaction and subsequently during service. The research was carried out on test samples of asphalt mixtures AC11 50/70 and AC11 PMB 45/80-75 for wearing course of asphalt pavements. The asphalt samples have been exposed to the effects of short-term and long-term ageing by the conditioning of loose mixture method. Subsequently, the stiffness modulus of asphalt mixtures at temperature 20 °C was determined by the IT-CY method according to EN 12697-26. The obtained results showed higher values of stiffness modulus for the mixture with paving grade bitumen 50/70. The largest difference in the stiffness modulus was recorded for origin asphalt mixtures. Furthermore, an increase in the mixture stiffness due to ageing was observed, more pronounced in the case of the mixture with the polymer modified bitumen PMB 45/80-75. Gradual ageing changes the properties of asphalt mixtures, which are essential for the durability of the road.