Evaluation of the rejuvenation of asphalt by means of oil-saturated porous aggregates

Abstract

Road degradation is an increasing problem for assets managers. Roads deteriorate mainly due to the combination of different factors, such as temperature, climate and traffic loads. This causes the asphalt to age and, consequently, the bituminous mixtures become more fragile and microcracks begin to appear. To eliminate these degradation effects, the most widely used performed actions are based on the renovation of the pavement to achieve an asphalt surface under acceptable conditions of use. In order to reduce the application of corrective measures when the asphalt pavement is already facing significant defects, it is important to perform regular preventive maintenance that minimise the renovation works of the pavement and improves the asphalt durability. This paper shows a method for the continuous rejuvenation of asphalt, by analysing the evolution of asphalt mixture stiffness and the resistance to cracking on asphalt mixtures with rejuvenator added after having been submitted to a laboratory ageing protocol (short and long-term ageing). The rejuvenator was added to the mixtures following either of these two procedures: first, directly added to the mixture and the second, saturated in porous aggregates, what the authors call encapsulated. Results from this study demonstrate the effectiveness of the second method (encapsulated rejuvenator) as an original solution to achieve long-term performance mixtures with reduced cracking